# Question
Title: Is there any other way to program the Lego Mindstorms NXT other than the provided software?
I'm curious to know if there is any way to program the NXT other than the provided software.

I don't necessarily have any issue with the software.

Does the program created by the software translate into an actual programming/scripting language? If so is that language proprietary to Lego or is it a common programming language?

# Answer
> 24 votes
The programming interface used by LEGO creates programs which make use of the standard firmware, that is, the one provided by LEGO.

If you look at alternatives (see also this answer for more information), you'll notice that quite a lot of them use the same firmware.

This means that the programs they produce use the same language which is interpreted by the standard firmware. One advantage is that you can have a mix of programs on the same NXT brick and it doesn't matter with what they've been originally written.

If you're interested to know more about the standard firmware and how to program it, you can download the Mindstorms Software Developer Kit. One of the interesting aspects of it is that you don't always need to create programs but you can send direct commands to the NXT as well - meaning you actual programming logic can sit on another connected device (PC, smartphone,...).

Others alternate languages use a different firwmare altogether, which means you can't mix languages at all. But if it uses a language you're more familiar with, it may be worth trying. (You can always revert to the standard firmware anyway.)

# Answer
> 14 votes
There are alternate text-based programming languages for the NXT. Three of the most popular ones are NXC/NBC, LeJOS NXJ, and RobotC. There are many more, all with their pros and cons, and are much more versatile than NXT-G, even on slow computers. I my personal favorite is NXC/NBC. But really it's up to you. The best way to see what suits your needs is to look at this table. It lists most of the pros and cons of the different programming languages. NOTE: it may be slightly out of date, but useful none the less.

# Answer
> 9 votes
---

> Please help make this post better! This needs:
>
> * **Clean up**
> * **Removal of irrelevant information** ~~plagiarized from~~ copied off Wikipedia
> * **Links**
> * \[Possibly\] **Pictures** or **Code samples**

---

---

## NXT-G

* Graphical programming environment
    + Uses Blocks
    + Based on LabView
    + Parallel "sequence beams" are actually parallel threads
* Comes bundled with the NXT
* The language supports virtual instruments for all LEGO branded and most 3rd party sensors/components.
* Community support is significant, for example, Brickshelf.

## Enchanting

* Graphical programming environment
    + Based on MIT's Scratch
    + Drag and drop
* Based on LeJOS VM.
* Fast.

## Robotary / Swift

* Mac IDE and robotics studio based on the Swift programming language
* IDE features
    + context-aware code completions
    + syntax highlighting
    + LLDB-based debugger
    + visual debug gauges
    + built-in documentation viewer
    + various examples
    + Bluetooth and USB support

---

> # HELP!
>
> The following section needs serious editing!

---

## C# with Microsoft Robotics Developer Studio

* Free tools Visual Studio Express and the Robotics Developer Studio allow you to program using the C# language.
* Sample Project on coding4fun
* Other languages are supported as well, including IronPython and VB.NET

# BricxCC, Next Byte Codes, Not eXactly C

---

## Bricx Command Center (BricxCC)

* IDE used to write, compile, and edit NBC and NXC programs for the NXT.
* Can flash different firmwares to NXT.
* BricxCC has many utilities, such as:
    + NeXTExplorer (upload/download files, defragment the NXT, use file hex viewer)
    + NeXTScreen (view what's on the NXT's LCD display, and capture images and video)

## Next Byte Codes (NBC)

* Open Source
* Assembly language syntax
* BricxCC can decompile standard NXT executables (.rxe) to NBC

## Not eXactly C (NXC)

* Open Source.
* Text based language.
* Based on C.
* Uses NBC as assembly language.
* One of the most popular third-party programming languages for the NXT.

---

## Robolab

* Older programming environment; originally used for RCX bricks.
* Version 2.9 has been updated so that it can be used to program the NXT brick
* Lego has announced that it will stop officially supporting Robolab but Robolab 2.9 is still available and there are still many user forums and other sources of help available.

## ROBOTC

* Developed by the Carnegie Mellon Robotic's Academy
* Based on C
* Used on VEX, VEX Cortex, FIRST Tech Challenge, and Lego Mindstorms NXT.
* Custom firmware for very fast program execution.
* Compresses files to increase available space.

## NXTGCC

* GCC toolchain.
* For programming the NXT firmware in C

## leJOS NXJ

* High level language
* Open source
* Based on Java
* Uses custom firmware

## nxtOSEK

* C/C++
* Requires custom firmware

## ICON

* To write files on the NXT itself

---

# MATLAB and Simulink

## MATLAB

* High-level programming language.
* For numerical computing, data acquisition and analysis.
* It can be used to control LEGO NXT robots over a Bluetooth serial port (serial port communication is part of the base functionality of MATLAB) or via a USB connection; for example using the free and open source RWTH - Mindstorms NXT Toolbox.

## Simulink

* MATLAB-based environment for modeling and simulating dynamic systems.
* Using Simulink, a user can design control algorithms, automatically generate C code for those algorithms, and download the compiled code onto the LEGO NXT.

MATLAB and Simulink code for LEGO MINDSTORMS NXT programming is freely available.

---

## Lua

* Port of the Lua
* General purpose scripting language

## Ada

* A \[http://libre.adacore.com/libre/tools/mindstorms/ port of GNAT\] is available for the NXT. It relies on a dedicated run-time kernel based on the \[\[Ravenscar profile\]\], the same used on the \[\[Goce satellite\]\]: this permits to use high-level Ada features to develop concurrent and real-time systems on the MINDSTORMS NXT.

## URBI

* \[\[URBI\]\] is yet another language and is a parallel and event-driven language, with interfaces to C++/Java and Matlab. It also has a component architecture (UObject) for distribution. Urbi is compatible with many robots, including Nao (cf Robocup), Bioloid or Aibo.\[http://www.gostai.com/nxt URBI NXT Page\]

## FLL NXT Navigation

## ruby-nxt

* Library to program the NXT for the Ruby programming language.
* Code is not compiled to a binary file; it is directly transmitted to the NXT via a Bluetooth connection.

## Robotics.NXT

* Haskellinterface to NXT over Bluetoooth.
* Supports direct commands, messages and many sensors (also unofficial).
* It has also support for a simple message-based control of a NXT brick via remotely executed program (basic NXC code included).

## LibNXT

* utility library for talking to the LEGO Mindstorms NXT intelligent brick at a relatively low level.
* is targeted mainly at the platforms that the official Lego Minstorms NXT software overlooks, namely Linux and other unices.
* It will work on any POSIX-compliant operating system where libusb 0.1 http://libusb.sf.net/ is supported.
* Windows support is also possible with the win32 port of libusb.

## PyNXC

* Translates Python code into NXC (see above) code, to compile and download to LEGO MINDSTORMS Robots.

---

(Some content from Wikipedia. Licensed under CC-Wiki, obviously.)

# Answer
> 6 votes
You can program the raw hardware:

The main microcontroller in the NXT is an Atmel AT91SAM7S256 (data sheet), which uses the ARM7TDMI core from ARM. This core is supported by gcc, so you can use GNU tools to program it in Assembly/C/C++.

You can build a firmware for the AT91SAM7S256 and load it via USB, after putting the controller in SAM-BA mode by a long press on the reset button.

There is also a smaller ATmega48 controller in the NXT, but it is not intended to be reprogrammed.

LEGO provides a Hardware Developer Kit among their support files. It contains schematics and descriptions of the sensors and motors, so that you know how the microcontroller is connected to the NXTs ports.

# Answer
> 4 votes
I started coding using NXT software and later EV3 and lately I have switched to java using leJOS. EV3 software ( and NXT ) is great for quickly hacking your ideas but when things get ugly the graphical language doesn't help at all.

Just watch what I needed to do to create a playable version of Pong for one player at http://thetechnicgear.com/2014/03/playable-pong-lego-mindstorms-ev3/

# Answer
> 2 votes
You can program the lego NXT in any language you wish! What is really the question is if you want the mindstorms brick to perform the decision making, or if you want some other device to do that for you. This works in two ways:

You download a program onto the NXT that it can run in its native format. Based on sensor input and the program which you've written, the NXT can operate by itself. This is how the mindstorms modules are primarely designed to operate out of the box - where you use their "visual" programming interface to create a program and then download it to the NXT.

As listed above, there are various other types of programming languages and interfaces you can use to write programs for the NXT. Eventually they require you to download them to the NXT - which will again be performing all the necessary calculations to run the program on-bard of the brick. These tend to offer you more control over your program however ultimately rely on the computing power available on the NXT.

The second scenario is to use the NXT as sort of a "slave" to another device with more computing power. This device - such as a PC or MAC, can be used to send down real-time direct commands to the NXT device to operate on. Based on feedback transfered back to the host computer, you can send down other commands. Using this method, you can use any programming language you are comfortable with - and simply use the NXT as a "dumb" device. This offers you the most verstility, and you can use virtually any programming language you are comfortable with.

What's nice about the NXT is that it allows you to use such a wide array of different techniques to control it - which makes it a great platform. One great walk-through of sending these direct commands over bluetooth to the NXT can be found here: http://www.robotappstore.com/Knowledge-Base/Programming-LEGO-NXT-Mindstorms/92.html I would recomend checking it out, since its a great introduction to getting started. If your computer supports bluetooth, you can easily download realterm (free) and get your robotic project working quickly!

I will admit that sending these direct commands to the NXT is a bit more advanced than say the type of visual programming used with the supplied Lego software, but it will allow you to use any language you wish, and with slight modification you can use your code for un-related projects too!

Hope this helps! -Ryan

# Answer
> 2 votes
You can use a python module called NXT-Python. If you know how to use python it will be very useful tool.

You can find it on GitHub. You can also use the package manager on some Linux distributions:

```
apt install python-nxt

```

Here you have some tutorials:

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Tags: mindstorms, nxt, programming
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# Question
Title: What would make these store display Star Wars sets particularly valuable?
I came across this display a trade show/swap meet. Now almost all the other toys/collectibles/etc. had a price tag on them (some were even in excess of $1,000).

However these Star Wars sets had a note that read:

> LEGO Store Display. One of the few remaining. NEED to sell, make reasonable offer to take home with you.

What would makes these sets valuable? Are they rare as the note claims? Are they valuable because they were a display a LEGO Store? Something else entirely?

I am not asking what a "reasonable" offer is, as that is subjective; rather is there something objectively intrinsic to the value of them?

Sets in question are:

1. 8036: Separatists Shuttle
2. 7754: Home One Mon Calamari Star Cruiser
3. 8039: Venerator Class Republic Attack Cruiser

# Answer
These displays are indeed rare, because LEGO demands that retailers destroy them after use, and most of them oblige. The sets inside are unfortunately glued together, so they don't have much value. They are valuable to collectors of displays, but that is a fairly limited audience.
> 2 votes

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Tags: star-wars, value
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# Question
Title: How to speed up the 4x4 Crawler truck 9398?
Just finished building the 4x4 Crawler and it was a fun build but as a remote control car it is . . . in a word . . . SLOW! I know it's powerful and can climb over stuff but sometimes there is nothing to crawl over and I'd rather it be faster. Are there any other gear configurations that would make it a bit more exciting?

# Answer
The simplest way to get different speeds is by changing the gears. The instructions get you to build it with a 12:20 gear down in the portal axles, so the easiest way to change the speed is to flip those to get 20:12. From memory that will not work because it interferes with other parts of the model.

You can fit two 16 tooth gears in there instead, giving a slight speed increase. Or you can put an 8:24 gear down for even more torque (but even less speed). There two options are shown below.

It's important that you keep all four wheels geared the same, otherwise you will be making the front and rear motors fight each other. That's not great for the motors and gears, and it will drain your batteries very quickly.

Deeper inside the model there is another 12:20 gear pair that you can also swap for 16:16 (two sets of this, one each end).
> 7 votes

# Answer
You need these old school 5292 puppies ;-) 2 of them.

Check a motor comparison here

You're gonna have to do some after-market mods but those are very powerful , I have them from the 8366 set. But as you can see in the review, there are pro's and con's on every engine.

I suggest reading it in full, it's an amazing source of information and you'll learn a lot like I did. There's a nice poster about them.

It has 2 different outputs which makes it so fun to make something that can use them both. Speed or torque. They will drain your batteries for sure anyway you use it.
> 6 votes

# Answer
You can switch 4 pairs of gears on each end of the crawler (2 pairs in the portal hubs and another 2 pairs inside the gearbox infront of the motor) do this on both ends or you run the risk of broken gears or premature motor wear. I ran 12 tooth gears all the way from the motor to my hubs for a dramatic increase in speed however the torque suffered severely, I would only recommend doing my gearing with xl motors. Cheers :)
> 1 votes

# Answer
What about this in comparison to Móż's?

The gist is to swap out two gears at the rear of the vehicle:

I see two solutions, but I don't know which is the better before I proceed to order pieces. One seems to be free, as it consists in switching these two gears in the image and/or the ones at the steering portal axles. Is there a difference between the two positions switching? Is the Móż's solution more balanced? Like having some more speed, but keeping enough torque power to remain a crawler?
> 0 votes

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Tags: technic, motor, set-modification
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# Question
Title: When did LEGO have a groove in the center tube underneath?
I have a bunch of bricks from my childhood, some have grooves in the tubes underneath, some have the old style bubble logo, some have square holes under the plates. I am interested in general ages of each.

# Answer
> 4 votes
I can give you some help, especially if you are talking about 2x4 bricks. Last year, I embarked on a bit of a history project to trace the design changes in Lego, by looking at the 2x4 brick, from 1949 to today. (Such as changes in the tubes, like the slots you mention!) I talked to several very helpful collectors (some here on Bricks beta!), who gave me lots of helpful information. I distilled it all down into this article:

http://snakeandboris.blogspot.com/2016/06/a-short-history-of-lego-brick-1949\_6.html

(This link goes to Part 2 of the article, because it contains a link for Part 1.) Keep in mind, though, that not all dates with Lego changes are hard-and-fast. You will see a few "c." meaning it was AT or AROUND that time--because as Lego changed molds, they didn't do it all at once, across the whole world. They used the old molds for their normal lifespans. There are even MORE sub-variations than what I have found, and there are links at the end of my post to some other good sources of information. Good luck! One thing about this hobby I can tell you, there are lots of knowledgeable and kind folks to help you!

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Tags: piece-information, history
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# Question
Title: Are creative play sets compatible with Duplo?
Are are the blocks in the Creative Play sets compatible with LEGO Duplo blocks? Also, are they the same size as Duplo, or Juniors or in between?

# Answer
Duplo bricks are twice (in each dimension) the size of regular bricks, and it's not hard to mix them, look for instance at the top related question (look in the right side). All the Creative Play-boxes I found in a quick search seems to bear the Duplo logo, meaning that they *are* Duplo, so of course they are compatible.
> 2 votes

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Tags: compatibility, duplo
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title: Need help identifying these sets

text:
# Question
Title: Need help identifying these sets
I recently got a huge bag of LEGO's. I figured out what some of them were, but there were still these left over, and I couldn't find anything about them.

# Answer
The parts on the left of the top photo are from 76020-1: Knowhere Escape Mission

the part on the right of the top photo is 30156pb02 : Panel 4 x 6 x 6 Sloped with Stone Wall Pattern

based on the windows it should come from 7785-1: Arkham Asylum
> 2 votes

# Answer
The bottom one is part of 6873-1: Spider-Man's Doc Ock Ambush

You can see the distinctive riser on the left.
> 1 votes

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Tags: set-identification
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# Question
Title: EV3 switch block does not recognize text?
i am using file access to input variables into my programm. text file is something like this: a b c ..

on each loop, program access file (using File Access block) and reads a new line "a" or "b" or "c" etc. and write this into a variable. I then use this variable as input for switch block. However switch block only recognized the very first character, while all others are very much all "false"

i know file access pulls out the information (i can display such input using the display block to show it..) yet for the switch block this information does not get recognized.

i tried with numeric, but i get the same problem..

Any ideas?

thanks!

# Answer
> 1 votes
It looks like you have found a bug in the file block. I am guessing that the text after the first line must have the a hidden newline character or something like that that causes it to not the switch block values.

However, I was able to get it working with numeric values.

Sample `data.rtf`

```
1
2
3
4
5

```

Sample code:

I also noticed that it doesn't work unless the file has Windows line endings (CRLF). If you are using Notepad in Windows, this is not a problem.

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Tags: ev3, mindstorms
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title: What parts make up this mini-figure?

text:
# Question
Title: What parts make up this mini-figure?
I need a little help in identifying the parts on this figure.

Here is what I need help with:

* The Hat/plume
* The Torso
* The Cape (though it looks like it might be made of two capes instead of one).
* The part that is holding the sword.

Hope the group can give me some help.

# Answer
Pirate hat: https://www.bricklink.com/v2/catalog/catalogitem.page?P=2528#T=C

Plume: https://www.bricklink.com/v2/catalog/catalogitem.page?P=4502c#T=C

Torso: https://www.bricklink.com/v2/catalog/catalogitem.page?P=973pb0665c01#T=C&C=11

Capes (appear to be two standard capes): https://www.bricklink.com/v2/catalog/catalogitem.page?P=522#T=C

Scabbard: https://www.bricklink.com/v2/catalog/catalogitem.page?P=95348#T=C
> 4 votes

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Tags: minifigures, minifigure-identification
---


# Question
Title: Can you identify the set for this transparent and printed orange canopy, with number 56?
Part from unknown set. Can someone please help to identify the set number?

# Answer
This is from set 4587-1: Duel Racers
> 5 votes

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Tags: set-identification
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# Question
Title: Where can I get the rest of the bags for the Helm's Deep set?
I have the Helm's Deep LEGO set from *The Lord of the Rings*. It is supposed to have 9 bags total, but I only have 4 of those bags. Does anyone know where I can buy the remaining bags?

# Answer
> 5 votes
I don't know of anywhere that sells bags of parts for sets, but you could try BrickLink \- you might be able to pick up a second incomplete set for a bargain - or more realistically, you can "Part Out" every component piece to a wishlist, remove those that you *do* have, and then look to buy the missing parts. It sounds daunting, but you can sort according to which sellers have the most parts from your wishlist, and hopefully get the bulk of them in one hit.

Your mileage may vary on prices. Like anything, rarity and availability dictates asking prices. Common blocks should only cost a few cents each, but anything unique to this set is likely to be hard to find and/or expensive.

# Answer
> 3 votes
Be aware that such larger sets often also contains pieces that are not in bags or are in un-numbered bags.

I'm not aware of anywhere where such bags are sold in any structured way. In the RLUG (Registered LEGO User Group) that I'm a member of (Byggepladen in Denmark), some members occasional get (or get the chance to buy) a box that contains a number of random bags from various sets, but it's rare that people bother identifying which set a bag is from, they are just opened are the parts sorted and put into the collection. If you are a member of an RLUG you might ask there, but it will probably require a lot of luck, but I don't see other possibilities.

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Tags: shopping, the-lord-of-the-rings
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# Question
Title: How can I find brick part number from a picture?
I found some books I like, but the book only give pictures of the parts. For example, this one

How can I know the part number (for example in bricklink) from the picture?

# Answer
> 7 votes
You'll need to start learning the nomenclature for those pieces.

For example the long straight pieces you have there with holes on top are "Technic, Brick 1 x 12 with Holes"

The pieces with rounded ends are lift arms. You can browse through the list of them here or take a stab at their descriptions using the width and number of pin holes. For example the purple on you have there is

# Answer
> 4 votes
* I find BrickSet a bit easier to browse for parts than BrickLink
* Alternately you could install LDD (Lego Digital Designer), find the name of the part, and then search with that name

# Answer
> 3 votes
It's good application for android - parts are sorted and easy to fine necessary part.

https://play.google.com/store/apps/details?id=com.betab.partsguideforlegotechnic

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Tags: part-identification, bricklink
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# Question
Title: How to connect two LEGO Bricks EV3 by USB using python
For some project, I have to use 7 motors with ev3 bricks. So I would like to connect 2 bricks using USB-USB link, and make them communicate, in python.

But I don't know how to do that, I've tried some stuff using serial module, but without any result.

# Answer
You can create a network connection between two EV3s using USB + ev3dev. Just enable tethering (the "Gadget" checkbox) on one of the EV3s. Connect the USB cable to the USB peripheral port on that brick (the small port next to the output ports) and the host port on the other EV3 (the USB port on the side of the brick).

Then, you could use something like RPyC to remotely control one of the EV3s. Here is an example that explains how to do this from a computer: https://sites.google.com/site/ev3python/learn\_ev3\_python/rpyc. So just substitute one of the EV3 bricks for the computer.
> 5 votes

# Answer
I have not tried this for myself. But as far as I know ev3dev does not support EV3 USB daisy chaining.

EV3 serial to EV3 serial over sensor ports should work. e.g. as an example https://github.com/ev3dev/ev3dev/issues/346 and https://github.com/ev3dev/ev3dev/issues/695 Make your own cable with a wire for ground, and cross-over wires for TX and RX.
> 2 votes

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Tags: ev3, ev3dev, python
---


# Question
Title: Found a bag of pieces. Most unique to this bag is a cloth of yellow and gold stripes
Most unique piece in this bag is a cloth of yellow and gold stripes. It has a hole in each of four corners. A number on the box that held this piece is 653999. What set does this go with?

# Answer
Based on the description on the cloth piece, the set should be the #31052 LEGO Creator Vacation Gateways https://www.bricklink.com/catalogItemIn.asp?P=26243pb01&in=S
> 5 votes

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Tags: part-identification
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title: Selling bulk LEGO

text:
# Question
Title: Selling bulk LEGO
I have most Star Wars sets, plus the complete Enterprise. They have been taken apart and I do not have all instructions. What is the best suggestion to sell? I also have the Death Star dismantled. I do have at least 6 Star Wars ships that are intact. If I sell those, how do I get them to the buyer?

# Answer
> 3 votes
An Enterprise has never been an official LEGO set. Lego does not have the licenses to produce Star Trek sets. Some clone brands have offered it, so I conclude that clone or custom LEGO is mixed into your bulk. You should filter the non-LEGO out of your bulk if you wish to sell it as LEGO.

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Tags: shopping, star-wars, transport
---


# Question
Title: Identifying kits to find instructions, red Ferrari with white mirrors and rear engine?
I am looking for what set number this is. It has Ferrari symbols on it. Any ideas so that I can find instructions?

# Answer
Looks like the red model from 8143-1: Ferrari F430 Challenge 1:17 without stickers.

You can find a link to the instructions from the link above.
> 3 votes

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Tags: set-identification
---


# Question
Title: What are the part numbers for the original brick minifigures?
I was gifted two containers of assorted LEGO bricks that had some of these:

Apparently these were only made for a few years before the minifigures we know now appeared in 1978. Does anybody know the part number for the legs, torso, and faceless head?

Slightly more info found here: https://en.wikipedia.org/wiki/Lego\_minifigure#History

# Answer
> 5 votes
Here are Bricklink entries for the:

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Tags: minifigures, minifigure-identification
---


title: How do you interrupt a MyBlock?

text:
# Question
Title: How do you interrupt a MyBlock?
I have a "general-purpose" line-follower encapsulated in a MyBlock that runs an infinite loop.

Now, in a client program, I would like to interrupt that MyBlock if some condition is met; what the condition is should be determined by the client, so I don't want to put that logic into the MyBlock.

I also don't want to terminate the program altogether, and I want to keep the loop in the MyBlock.

Is there a way to break out of the MyBlock?

# Answer
You can use the Loop Interrupt block. Just make sure the name used in the Loop Interrupt block matches the name of the loop inside of the My Block.
> 3 votes

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Tags: programming, ev3-g
---


title: Is there a 90 degree angle brick?

text:
# Question
Title: Is there a 90 degree angle brick?
Is there a brick that I can use to connect LEGO plates at a 90 degree angle?

# Answer
> 10 votes
There are many different types. You can find them here: Bricklink - Brick Modified

There are also Brackets: Bricklink - Brackets

And you could use some of these Bricklink - Plate Modified or, of course, these Bricklink - Hinges

# Answer
> 6 votes
The part# 87087 - "Brick, Modified 1 x 1 with Stud on 1 Side" could work:

But the part# 11211 - "Brick, Modified 1 x 2 with Studs on 1 Side" seems better to scale up with:

# Answer
> 4 votes
There are many. I believe the classic "Erling"/headlight brick (it was designed by a guy named Erling) is the oldest way, but there's also a number of bricks with studs on the side and a number of brackets.

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Tags: building, angles
---


# Question
Title: Why are pat pending bricks rarer and treasured more than patented bricks?
My mum and I share a love of LEGO, but she is a huge collector of LEGO with easily 100kg spread across the garage, her room and my nan's garage.

When she gets time to sit down and sort through her immense collection, she's always more excited when she comes across a brick which has "pat pending" written on it. She has spent hours searching for pat pending bricks to complete an entire retro set out of this brick type.

I want to know why two otherwise identical bricks can be so different in importance - a standard brick vs a pat pending one - to an avid collector of LEGO, when to me, they are otherwise the same and I'd probably mix them up by accident.

# Answer
> 6 votes
As I understand it, "Pat. Pend." bricks were made in the 1960's.

Later around 1970 they removed "Pat. Pend." by carving it out of the molds, so there is a lump in place of it. These are sometimes called "Pat. Pend. removed". Those ran until 1976-ish?

I don't think any of these bricks are much more valuable than the others. Old generic bricks aren't generally worth very much. If one wanted to have genuine 1970's pieces for personal reasons, I guess they might look for these markings.

I don't think all pieces had those markings though.

# Answer
> 5 votes
They are rarer because fewer exists, they were made a long time ago, and LEGO has procuded many more elements since.

They are treasured by some because some collectors value having accurate bricks in their old sets, because they get that bit more authentic. I only care when there's a more easily visible difference like a groove on 2x2 tiles, or open/closed studs on round 1x1 bricks (and it that case I care more about using the right ones where visible). In some cases this can mean the prices for the old pieces are a little higher, but the condition of such old elements often detract from the price, so don't expect to make a lot of money selling those parts of your mom's collection.

# Answer
> 4 votes
If you're selling an old set, you naturally want it to be made of old bricks. How would you like to buy a 1960's set, paying a vintage price, only to find that its bricks are 2010 vintage? Such a set must be comprised of bricks of its era. That why pat-pend bricks are important.

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Tags: history, vintage
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title: Billund Legoland car controls

text:
# Question
Title: Billund Legoland car controls
I just visited the Legoland's Miniland. There are numerous car models that drive around the landscape under some sort of remote control. One can see the models stop to recharge on pads with two wires sticking from the ground, but there are no visible guides for the robotic cars to follow.

How are the cars controlled and how do they follow their tracks? Similar info on the trains would interesting as well.

# Answer
From an unofficial Legoland Windsor fan site 'Completely LEGOLAND Windsor'.

> **Road Vehicles**
>
> The cars, lorries and buses all appear to move and steer on their own, never leaving their set paths, yet not using any rails. How on Earth do they manage that? Beneath these paths are cables that emit a low-level radio wave specific to each vehicle - the vehicle picks up this signal, and uses it to steer. When the vehicle reaches one of the charging points dotted around it's track, it stops. One of the computers registers this, and a timer is started. When the timer reaches zero, the power to the charger is cut, and this signals the vehicle to continue along it's path. Outside park opening hours, the vehicles stop on the charging points and recharge fully overnight.
>
> **Trains**
>
> The trains work in a similar fashion to the road vehicles, but follow tracks instead of radio signals. When a train approaches a station, the train passes over 'slow down bars', which tell the onboard microprocessor to slow the motor. When it reaches a charging point, one of which is located at each station, a signal is sent to the control room, at which point a timer is started both in the control centre and in the train's microprocessor. Unlike the road vehicles, which can only go forward at a certain speed, the trains can go forwards, backwards, and vary their speed.
>
> **Boats**
>
> The boats are attached to rubber loops, which can clearly be seen under the water. These are driven by motors controlled by the computers in the control centre. A piece of metal on the hull of the boat allow sensors along the boat's track to detect the boat, and let the computer know where the boat is. The computer then uses this information to initiate various sequences, such as raising bridges, or opening and closing locks and powering water pumps.
> 2 votes

# Answer
They are robotic and follow a magnetic track.

Source: I asked a LEGOLAND California Master Model Builder back in 2006.

---

I don't know about the trains, but I suspect they are simply electrified rails, much like the old 9V train tracks.
> 1 votes

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Tags: legoland
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title: LEGO EV3 I2C Compatibility

text:
# Question
Title: LEGO EV3 I2C Compatibility
I'm having difficulties with communication between the EV3 and Arduino boards. Does anyone know if the EV3 is really I2C compatible, or is it just close enough?

Background: I can get the EV3 to send and receive I2C with an Arduino Uno, but not with MKR1000 or Adafruit Huzzah boards. This is both with and without pull-up resisters, and also trying different values of pull-up resistors. When I scope the SDA line, it look reasonable when communicating with the Uno. When communicating with the MKR1000, the low logic level only reaches 1.6 V (with the 4.7k resistors desoldered from MKR1000 board, but looks worse with the pull-ups). With the Huzzah board, the SDA line looks great for about 4-5 bits, but then also raises the logic low level to about 2 V. The clock line looks clean no matter what it is connected to.

# Answer
> 4 votes
LEGO doesn't really follow I2C standards, so "close enough" is a good description.

The EV3 hardware developer kit (available for download at http://mindstorms.lego.com) has this to say:

> ### 4.1 I2C communication
>
> The EV3 platform supports the same level of I2C communication as MINDSTORMS NXT. This means that system support a maximum of 9600 bit/s and maximum 32 bytes communication buffers. All I2C communication is running within software drivers. External devices are required to include pull-up resistors on both pin 5 and 6 on 82K ohm. If multiple sensors are used on the same bus the total impedance needs to be adjusted accordingly.

Most off-the-shelf I2C devices use 10k pullup resistors (although it looks like it might be 4.7k in your case). These must be removed and replaced with 82k resistors to be compatible with MINDSTORMS.

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Tags: ev3, mindstorms, electronics
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title: Can LEGO Boost play custom audio files?

text:
# Question
Title: Can LEGO Boost play custom audio files?
Can LEGO Boost play custom audio files on the Boost app from files kept on the device such as those downloaded from iTunes or transferred from a computer?

Are recordings from the tablet the only way to use custom sounds?

# Answer
> 4 votes
As far as I can tell, recordings from the tablet are the only way to use custom sounds at the moment. I imagine that the UI for a feature like this was deemed too complex for an app designed for children under 12. However, this should be easy to add to the app in a future update if there is demand for it.

One obvious workaround for this is to play the desired sound on another device and save it using the recording interface:

These recordings are limited to about 5 seconds.

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Tags: boost
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# Question
Title: EV3 motor control proportional to another motor when more than two motors
From what I understand, in EV3-g you can use "move steering" or "move tank" blocks to regulate two motors proportionally to each other as they have a built-in PID controller to do that. If one motor falls behind, the faster motor will be slowed down and vice versa...

My question is how to realize this with 3 or more motors? E.g.: I have motor A which I want to run at full speed. Motor B which I want to run at 30% of the speed of motor A. Motor C which I want to run at 50% of the speed of motor A. I also want that if any motor is slowed down (e.g. because of friction), this is compensated by slowing the other motors down.

Will I need to code extensive PID loops myself? Does anyone have any references or examples in that case? Or is there a simpler way ?

The application I have in mind is an omni platform. This is a robot that has three wheels on axes that are 120 degrees separated. By correctly setting the speeds of the three motors, one should be able to get the robot to drive in any direction without it having to turn (although it can turn in place if needed).

# Answer
I've implemented **3-motor triangular holonomic drive** with NXT-G but not ev3-g so I can help with strategy but not tactics.

To accelerate in any direction you need to constantly re-calculate the power levels for each of the 3 independent motors. By constantly I mean some reasonable number of times per second - 4, or something like that. EV3 is considerably more powerful than NXT-G but you won't want to tax it too much with this, if the 'bot does anything else at the same time.

The built-in PID stuff won't help with this at all - in fact, you'll want to do everything you can to ensure only your code is controlling the power levels of each motor, that nothing else is affecting them. Anything that's smoothing out the power level or similar should be disabled as best as you can.

Trigonometry is what you need - Arctan() to be specific. I have the math jotted down on paper somewhere but odds aren't good I'll find it anytime soon. If I can, I'll extract the logic from existing NXT-G programs and update this answer sometime.

inputs: desired bot direction, desired power level, motor angle (0, 120,240)

output: power level goal for that motor

You might wrap that all up in a PID loop to get 'actual' numbers closer and closer to 'desired' numbers.

Hope this is helpful. Happy to field any follow-on questions you might have. I'll update this answer with additional details if I'm able to pull them from the actual code, or if I find the notebook where I wrote down the math, about a decade ago.
> 1 votes

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Tags: ev3, ev3-g, motor
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# Question
Title: Run an NXT 2 program that will continue until no power is left in batteries
I want to run an NXT 2 program that will continue until no power is left in batteries. I want it to rotate slowly so that a sculpture can be turned for as long as possible. It seems to go for a few hour then shuts down.

# Answer
Use the **Keep Alive Block** in your program.

> This block will keep the NXT from entering sleep mode. Add this block if your program needs to wait for longer than the NXTs set "sleep time" (configured using the NXTs on-board menus).

The *Time until sleep* plug will take a value from 0 - 4294967296 (168) milliseconds .

4294967296 milliseconds is just over 49 days which is most likely a lot longer than the battery lifespan and much, much longer then you would/should normally be running it for.
> 1 votes

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Tags: nxt
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# Question
Title: What internal electronics does LEGO Boost use?
What specific electronic components are present inside the Boost Move Hub?

# Answer
> 9 votes
Here's what the main board in the Move Hub looks like from the top:

And bottom:

The Move Hub includes the following hardware:

# Motors

The two built in motors are fairly standard DC motors. They include optics in the early stage of the gearing for rotation counting.

There are two LB1836 motor drivers on the board. They are dual channel parts, so presumably one is for driving the internal motors (A and B), and the other is used for driving the external ports (C and D).

# Communications

Boost uses a BlueNRG Bluetooth Low Energy (BLE) processor from STMicroelectronics for communication with the control device. More information is available here:

http://www.st.com/en/wireless-connectivity/bluenrg.html

This processor is fairly powerful in it's own right. Internally, it includes a 32 MHz ARM Cortex M0 with 12KB RAM and 64KB flash. This chip is significantly more powerful than the main processor in the RCX line.

# CPU and Memory

The main CPU in Boost is an STM32F070 RBT6 from STMicroelectronics. This includes and ARM Cortex M0 internally. It has the following specs:

* 48 MHz clock
* 16 KB RAM
* 128 KB Flash

This part is in the same neighborhood as the CPU used for NXT in terms of clock speed and available storage.

# Other features

There is a single push button present on the board to turn the device on and a single RGB LED that can be programmed via the Boost app. The battery box hold 6 AAA batteries providing 9V.

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Tags: electronics, powered-up, boost
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# Question
Title: Can you identify these LEGO animals, mountains, and minifigs?
Came across this package 2 of a larger set. I could only upload several pieces of it. Can anyone identify this for me please?

# Answer
> 6 votes
You have bag 2 of set 60014: Coast Guard Patrol.

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Tags: part-identification, set-identification
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# Question
Title: What is this piece slightly longer than a 2x2 plate with grooves and a hole?
Once again, I need the collective wisdom of this group to identify a mystery LEGO element!

I did a search for "2x2"and went through scores of Bricklink pages, but I couldn't find this particular piece.

It's the size of a 2x2 plate, but with this added grooved part that I've never seen before.

# Answer
This looks like a PLATE 2X2 ANGLE, which is broken. There is a rough side shown on the picture.
> 31 votes

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Tags: part-identification
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# Question
Title: Are limited run sets a good investment if left unopened?
So I've been reading a lot about the LEGO aftermarket, and how many will hunt for sets that have gone out of production and will pay sometimes an x multiple of the Retail price for it.

1. How long does this process of accumulating value usually take?
2. What is the best way to select newer sets for this kind of investment?

# Answer
The LEGO aftermarket is changing all the time and there are no defined rules on how a set will appreciate. Over at http://www.brickpicker.com you will find an entire website (plus forum) dedicated to investing in LEGO sets.

The post-EOL rise in price of a set is driven by many factors, some of which are:

**Availability** If a set is only available for a limited time on store shelves (typically a year or less), it might see an increase in price after it retires. Alternatively, if a set is available for longer than a year, but frequently goes out of stock during its shelf life, it might also see an uptick in value post-EOL.

**Exclusivity** Some sets are not available via all retail channels (and some are even more limited in distribution like the SDCC sets or the Employee Christmas Gifts). Typically, the more a set is limited to specific channels, the more likely it is to appreciate in value.

**Desirability** Sets with broad appeal across multiple age groups, or of a subject matter that has a very loyal fan following (think Star Wars, the Beatles, anything Science related) typically do well post-retirement.

**Collectibility** A lot of the post-retirement increase in price has to do with people collecting an entire theme. Often this collecting does not happen from the start of the theme, and people play catch-up to grab older sets that might have already retired. Some examples of this phenomenon are the early Modulars (Cafe Corner, Green Grocer), Series 1 Microfighters, Series 1 Speed Champions, and the early Star Wars UCS sets. A more recent example is the Elves Dragon eggs series, which had a short run and contained one set specifically which acted as the collection base of all eggs (41178 Dragon Sanctuary), which happened to have an extremely short shelf life (4 months in the US).

**Rarity of parts** Finally, some sets see big post-retirement price gains because they contain rare or desirable parts. A key example of this is set 44027 Breez Flea Machine from the Hero Factory theme. This set commands a significant premium on the aftermarket purely due to the inclusion of 3 copies of part 92222 - Hero Factory Shield with Handle for Clip. 6 of these pieces are required to make the SDCC exclusive Bat Pod, which is much desired by collectors.

BUT, a big word of warning: for each of the above factors one can find sets that clearly show an increase in value but also numerous examples of sets that should have seen a sharp increase in value, but somehow didn't. Plus, with The LEGO Group's prepensity for set remakes, a set can see a climb in value, only to be followed by a plateau or even drop off following its initial increase. There are no sure-fire winners (and don't believe anyone who says they know one).
> 5 votes

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Tags: shopping, investment
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# Question
Title: How can I connect the LEGO Mindstorms NXT with an iPad?
I'm looking to take advantage of the older generation LEGO Mindstorms NXT robots by developing a companion app for the iPad. I'm aware that non-jailbroken iPads cannot communicate with the robot via bluetooth, but is there a way to send code from the iPad to the NXT robot through the USB port?

Is there another way to have kids write code from the iPad which makes it onto the robot without using another computer?

# Answer
I'm going to guess that USB would most likely required a jailbroken iPad. The NXT uses a custom USB protocol, so you would need raw access to the USB via IOKit.

If neither Bluetooth nor USB works, then there is no alternative other than using another computer to communicate to the NXT.
> 1 votes

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Tags: mindstorms, nxt, ios
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# Question
Title: Exist some piece official or unofficial of Lego with the names of the minifigures?
I'm looking for a brick like this:

Or similar **with the name of the minifigures from the saga star wars**, i want it for my minifigures collection. Exist some like this or an unofficial option?

# Answer
> 4 votes
That part is Tile 4x4 with studs on edge. It's available in many colours but there are only a small number of printed variants. Rebrickable shows 27 printed variants, 12 of which are Star Wars prints like the one in your question.

I'm not aware of any third-part labels or stickers but you could probably print your own if you're handy with Photoshop or the like. The black unprinted version of that part is very cheap on Bricklink.

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Tags: star-wars, bricklink, bricks-and-pieces
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title: Are COGO and LEGO bricks compatible?

text:
# Question
Title: Are COGO and LEGO bricks compatible?
Is COGO compatible with LEGO sets, that is can I combine parts from both packages? My kid got a COGO set on his birthday recently, which we did not open because I think we can return and exchange (for a surcharge) it at toy store where it was bought, if they can not be used together with LEGO bricks that is.

# Answer
Welcome! COGO is a clone brand, and hence not generally used around here. COGO bricks will work with LEGO, however, the quality, finish and fit of COGO bricks is significantly less than LEGO's, so I would advise to return the COGO set and buy a (smaller but) better quality LEGO set instead.
> 7 votes

# Answer
Yes COGO are compatible with LEGO. And I wonder why we don't find them easily - I love them. And it works great for missing LEGO peices.
> 0 votes

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Tags: sets, compatibility, clone-brands
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# Question
Title: Is there a named scale for sets such as 75055 Imperial Star Destroyer or 75054 AT-AT
I am looking for the name of the scale that most Star Wars sets use, that isn't minifigure scale as it has been scaled down to an appropriate size but still has an interior for minifigures, such as the Star Destroyer 75055 or the AT-AT 75054? Is there a specific name like there is for minifigure scale and Microscale?

# Answer
> 4 votes
As far as I can find, there are very few official "scale" terms used in LEGO. The term "Minifig-scale" is a fan term and is fairly loose, as the scale of the figs themselves don't really equate to reasonable human dimensions. Add to that the fact that minifig-scale vehicles and buildings have had variable relative sizes compared to minifigs, making it difficult to describe a standard scale that is officially used in LEGO sets.

There are a few "micro-scale" sets, including Micro Scale Space Cruiser, Micro Scale, and Micro Scale Bag End. And, if you will forgive a bit of levity, there is the Kitchen Scale.

My favorite scale that LEGO officially produced was the Midi-scale Millennium Falcon). However, they also did a Midi-scale Star Destroyer that is totally NOT the same scale as the Falcon. So, even in their official terminology the "scale" is a rather fluid thing.

For a more indepth discussion of scale, they had one over on the Brickset Forums. I particularly like MrShinyAndNew's answer (third one down as of this post).

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Tags: sets, star-wars, terminology, scale
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# Question
Title: Help identifying LEGO set with yellow construction vehicle arm?
Could you please help identify this partly assembled set? I have already scoured the Internet looking for images to no avail. I have looked through the instruction books we have. It has possibly come in a job lot purchase. Many thanks.

# Answer
> 6 votes
This is from: 60122-1: Volcano Crawler

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Tags: set-identification, city
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# Question
Title: Help identifying this set, dark red and dark grey airplane body?
Bought in a random box with mostly Star Wars, Indiana Jones, and Ninjago sets, and a few one offs. Before I have to enter every piece into rebrickable, I was hoping someone might be able to identify this?

# Answer
This is from 9467-1: The Ghost Train
> 5 votes

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Tags: set-identification
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# Question
Title: 42042 Crawler Crane: conversion to remote control
After many years of "Lego drought", I have decided to reinvest in some. Amongst a lot I have purchased is a Crawler Crane, half built, with all the parts to complete the build.

However, instead of building as the instructions, has anyone here actually converted this to remote control, so you don't have to keep reaching for the back of the crane to operate the shift levers?

I've seen a few videos on YouTube, but they don't explain the how to make the modifications.

# Answer
There's a nice looking mod on Rebrickable that includes full building instructions.

This includes the following PF components:

* 2 L-Motors - drive
* 1 M-Motor - tilt cab
* 1 M-Motor - boom elevation
* 1 M-Motor - rotate
* 1 M-Motor - winch
* 3 IR Receiver
* 3 IR Remote Control
* 1 Battery Box
> 8 votes

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Tags: technic, building, set-modification
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# Question
Title: How does LEGO decide the color of internal set pieces?
While building many LEGO sets I have noticed that for internal pieces you cannot see when the set is finished; LEGO often chooses mis-matching colors. For instance in the (amazing) Saturn 5 set most of the pieces are of the white, black, gray family. However there are some green/blue internal pieces. Doesn't match the rocket at all. I have noticed the same thing with other sets as well where a random green internal pieces will show up.

Do they do this for a reason? Are they using colors that don't sell well and trying to get rid of them? Going for contrast to help you build?

# Answer
> 9 votes
> Going for contrast to help you build?

This is probably the primary reason most of the time.

One Eurobricks user once said they asked a set designer about it, and they confirmed they do it to makes it easier to follow the instructions:

> I had an opportunity some time ago to talk to a designer at TLG, and he told me that they use other colors to make it easier to follow the instructions and build the model.

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Tags: design, colour
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title: Centering on Stud.io (design software)

text:
# Question
Title: Centering on Stud.io (design software)
I'm trying out Stud.io for the first time and I am unsure how to centre a part I want.

I am used to just right clicking on the part to centre it on screen in LEGO Digital Designer, but this won't work on Stud.io as it just brings up options. Is there a way to do this?

# Answer
> 2 votes
You are almost there: Right-click on a part. One of the options is "set as origin". This centers the view on this part. "Reset origin" does exactly that.

Otherwise, navigation is done by rotation (rmouse+move), panning (`space`+rmouse+move) and zoom (scroll).

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Tags: ldd, bricklink-studio
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title: Is it part of an offical set?

text:
# Question
Title: Is it part of an offical set?
Does this assembly look familiar to anyone? I've identified the two trans-light blue 4x1 tiles and looked up and down the list on Bricklink but none of them look right.

# Answer
You could cross-check the sets with the transparent 1 x 4 tile and the transparent 1 x 2 plate. No matches jump out at me.

Unfortunately, I don't know of any tools to make crosschecking easier.
> 3 votes

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Tags: set-identification
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# Question
Title: Identify unknown LEGO set bag 2, clear tubes with blue center and blue minifig with clear helmet?
Everything is grey and blue, there is a robot/alien type guy with a clear helmet, there are 2 oversized light blue hands and some long rubber, flexible things leading us to believe he's controlling a robot. Possibly from a Marvel or Star Wars set. Lots of small clear blue pieces.

# Answer
> 3 votes
This is part of 70901-1: Mr. Freeze Ice Attack

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Tags: set-identification
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title: AA Battery Packs 54950c01 vs 59510c01

text:
# Question
Title: AA Battery Packs 54950c01 vs 59510c01
What is the difference between these two battery boxes, 54950c01:

and 59510c01:

except for the on/off button?

Which electrical connectors are compatible with each of those?

Is there a counterpart for the 54950c01 button to make it similar to the 59510c01 one?

Are these interchangeable in order to connect them to a buggy motor 5292?

# Answer
The main functional difference between these is the electrical connector. The one with the red switch uses the old style 9V connection, while the one with the orange switch uses the newer Power Functions connector.

These are both the same voltage (9V), and you can mix the two systems using the Power Functions Extension Wire (8886).

Here's an example showing a PF battery box powering buggy motors:
> 6 votes

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Tags: technic, power-functions, electronics
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# Question
Title: How to best transfer power at 90 degrees for high torque applications
So, I am building a tank model and this is the transmission I have been working on:

Description: There are two gear pairs for gearing up (16t to 8t gears) and one gear pair for gearing down (worm gear to 8t gear hidden beneath it) for each of the two M motors. The final gear ratio is 1:2 resulting in half the speed and twice (roughly) the torque of the M motors. The grey 24t gears are the ones who transfer motion to the tracks.

Questions: I would like to know if there is a better way to transfer the power of the two M motors to the 8t gears which are located beneath the worm gears. The problem I have is that the worm gears I use require a lot of gearing up to rotate fast enough (even what I achieved above is not enough). The additional gears result in lost energy and more points that could potentially break. Specifically I want to know if it is possible to achieve similar gear ratios with less gear pairs? Also are there any tips that would help me reduce the size of the above configuration? Is there an entirely different configuration other than the above which would lead to better results (gear ratio preferably less than 1:2, tougher)? Should I prefer bevel over normal gears? Is it worth it upgrading to two L motors? And lastly do you have any general tips regarding transmission and tank building?

# Answer
There are plenty of gears designed for 90 degree, search bricklink for "technic gear bevel" and "technic gear crown". There's also the "technic knob wheel", that seems to be used a lot outside technic, but I have a feeling that goes badly with a motor.

In my building the only application for worm gears is to gear things down, with regards to to size you can't beat the solutions it offers. But you're first gearing up to then gear down, that looks silly.
> 2 votes

# Answer
Ok, I think I found a nice solution using only 3 gears per motor (instead of six). Now the moc can actually move and quite fast because of the 1:1,5 gear ratio. Thanks to everyone who helped!
> 1 votes

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Tags: building, gears, motor
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# Question
Title: Is there any way to connect “sideways” to an axle?
There are some pieces whose middle part is shaped like a Technic axle, but that have elements on both ends that make it impossible to insert them into a normal axle or Technic hole:

This makes me wonder whether the axle shape here actually allows for a connection or was only chosen for stability, production reasons, or similar. With other words, is there any piece (or combination of pieces) that connects a Technic axle “sideways”, i.e., without going over the ends?

# Answer
I don't think there are any pieces LEGO intends for you to attach to the side of these axle shaped pieces. However, I'm pretty sure you could attach piece 32172 to some extent (assuming the piece being attached to is actually the right size for an axle):

It probably would not connect very well, only the clips on the sides of the socket would hold it, so it would probably slide easily, or pop of with little effort, but it could be attached.
> 8 votes

# Answer
The minifigure spanner can be attached sideways to an axle (as well as a pin and stud):

This doesn’t hold in all directions, however.
> 5 votes

# Answer
This part (Technic, Link 1 x 16 #2637) appears to be an axle with two connectors on each end. Bricklink classifies this piece as a Technic Link and not an axle because it doesn't perform most of the same functions as an axle.

I believe the decision to use the Technic 'axle' shape for the length of the piece rather than a round piece, is because it functions more like an axle than a pin. Pins connect bricks together and are two to three bricks long. Axles can be much longer, one of which is the same length as this piece.

Of the 23 sets this part appears in there aren't any sets in which bricks have been attached to the axle part of the piece, nor does there to be any obvious way to do so.
> 2 votes

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Tags: technic, piece-information, connections
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# Question
Title: I am looking for robot constructor general plastic parts
I do not know how call it, but I mean something like these pics:

Can I find something like this plastic parts in general or I must design them in solidworks and ordering for mold production by myself?

My goal is to build some educational robot kits for kids by this parts.

# Answer
The first picture is from Elector, the second is kai robot.

They are both robotic kits from Iran, you can order kits from their site.

If you are looking for a Lego solution,
the Lego Eduction program has robotic kits like Mindstorm and WeDo, or you could look at Lego Boost
> 3 votes

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Tags: plastics
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# Question
Title: Help me identify this set? Rocky terrain with castle walls?
My brother has handed down some of his old LEGO to my kids . He had sets including Star Wars, Harry Potter, generic Lego, Batman, and Lord of Rings collected between the years 2006 and 2013.

These pretty unique pieces were in the box, and I feel like they are Lord of the Rings. However, I can’t find any sets that have pieces like these.

Any LEGO fans know what set this may be? I have tried using few sites to look up individual parts in hopes of finding the set, but no luck thus far.

# Answer
> 8 votes
From the Megablok wiki:

9650 Raiders Keep

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Tags: set-identification, clone-brands
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# Question
Title: What were the most and least popular LEGO themes?
I know that Lego has a history of both popular (Lego city) and non-popular (Jack Stone) themes.

However, is there any hard data that back up popularity?

What were/are the most popular Lego themes/sets of all time and were what the least popular?

# Answer
By definition, the popular themes are the ones that sell well, and the unpopular ones sell less well.

TLG are in the business of selling LEGO. It makes business sense for them to offer for sale themes that have already proven popular, and withdraw from sale those themes which are least popular.

Based on these two observations, it seems obvious that themes that have a long run are typically the popular ones, whereas those that don't last long are less popular.

One major caveat to this line of reasoning is that TLG focuses on total profit, rather than total sales, so even of a theme is popular, TLG may still withdraw it if it doesn't make money. For example, lots of people claim that they would buy monorail sets if LEGO made them again, but TLG's research suggests that the cost of the moulds would make them unprofitable.

There will be other exceptions, too. For example, LEGO might only have a short run of licenced theme, not because it is unpopular, but rather because f the ternms of the licence. And, on some occasions, LEGO might simply make a mistake, and stop a theme too early or too late.

Nevertheless, the long running themes will generally be the ones with the best sales, ie. they will be the popular themes.

So, based on all this, I suggest that LEGO's own catalogues are a good source of information on which themes have proven popular, and which have been less so.

Assuming I'm right, I would say that **City** is the most popular non-licenced theme, with **Police** being the most popular sub-theme.

**Star Wars** is clearly the winner on the licenced front.

Least popular is harder to judge, because there are lots of themes that have only lasted a single season. Juding by the slating it gets, **Galidor** wasn't popular, but I don't have figures to back that up.

I'd be interested in actual numbers, if anyone has them; but do bear in mind that TLG may have commercial reasons for not wanting to share the whole story.
> 4 votes

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Tags: sets, popular-culture
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# Question
Title: Can anyone identify this white air/spacecraft please?
Can anyone help me identify this air/spacecraft please?

# Answer
> 7 votes
This is part of the Justice League Javelin from 76028-1: Darkseid Invasion

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Tags: set-identification
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# Question
Title: Why does the Brickset inventory page incorrectly list a set as including 200 of a part when it actually includes more?
One example of this issue would be a set like 42056 that has 516 black Technic pins with friction. Brickset lists it as only having 200. Is this a technical limitation of some kind? What causes this?

# Answer
This doesn't have anything to do with database limitations or anything like that. Brickset scrapes their inventories from the replacement parts list on LEGO.com:

https://www.lego.com/en-us/service/replacementparts

Normally, you are able to request as many replacement parts as there are parts in the set, so this is the number that Brickset uses for it's inventory count. Unfortunately, the max you can request is 200, so Brickset doesn't list more than 200 of the same part being found in a set.
> 10 votes

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Tags: inventory
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# Question
Title: Programming to get data from EV3 sensor and send it to a server?
I am using EV3 with Linux V1.09 and I am doing a project in which I want to send the sensor data from the EV3 to a remote web server using POST method - is this possible?

# Answer
> 1 votes
Another possible method is to use I2C to communicate from the EV3 to an Arduino with a WiFi shield or module, then have the Arduino perform the POST.

# Answer
> 0 votes
Yes, it is possible.

If you are using the official LEGO firmware, you will need a computer that reads data from the EV3 using direct commands, then relays that information to the web server.

The EV3 could send the information directly if you use a 3rd party OS for EV3, such as ev3dev or leJOS.

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Tags: ev3, mindstorms
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# Question
Title: Why are these bricks slightly shorter than normal?
I have two red 1×6 bricks that are slightly shorter than normal and also a bit deformed. For comparison, I here show them together with regular 1×6 bricks (the regular brick is the top one of each pair):

These bricks are shorter to the extent that considerable force is needed to connect them to regular bricks (note how much they are worn down). I suspect that they are rather old and made from some different material, however, I have many older bricks which connect considerably better to modern standard bricks.

Thus I wonder and ask: **What could be the deal with those bricks?** They are part of a huge connection containing second-hand bricks, so I cannot say much about their origin, except that they are from the last century.

# Answer
For starters, having that as a production error is completely impossible, given the industrial precision of our beloved bricks. The LEGO group has been incredibly careful for decades about the tolerance of their bricks' dimensions:

* You can read this WIRED article where the author compares old and new bricks' dimensions (TL;DR: they have been making really precise bricks for *decades*).
* Their current standard for tolerance was 10 micrometers in 2009 - see page 20 of official LEGO documentation.

I think we can discard that option.

As @SlicksterTheBrickster said in his answer, the shorter bricks seem warped. The most plausible explanation is that extreme heat made the ABS plastic bend and get a little thicker on the walls or a little taller (floor to studs distance). ABS is a thermoplastic polymer (as opposed to a thermosetting one), meaning that it cannot withstand intense heat and it will melt. As an example, it's normal to wash and disinfect bricks with water at 40°C, but if you increase that to maybe 60°C or 70°C the plastic will start getting "plastic" (i.e. moldable). ABS is an amorphous material, meaning that it doesn't have a proper melting point and it transitions slowly (like glass). I would say that you can get the effect that you show by building a model and leaving it e.g. in a closed car under very hot sun with some pressure on the sides or strong torsion, or maybe close to a stove. The bricks will slightly bend and/or deform after the episode.

If you are curious, get a caliper and measure both bricks' height and width at several points all along their length, and do the same with the walls' width. I'm almost certain that the shorter one will have a significant variation in those values. If your question is "But where did that material go?", it went into slightly swelling the walls.
> 6 votes

# Answer
My thinking is that since the older and shorter brick looks a little warped, perhaps it was exposed to heat which caused the plastic to melt a little. I can't say this would be a production error as the pieces are injection molded and imperfections are kept down to a fraction of a millimeter.
> -1 votes

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Tags: vintage, plastics
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# Question
Title: Which LEGO set is best suited to build robots?
My goal is to build some educational robot kits for kids and so I'd like to know if there are any LEGO sets that let you build almost anything or can you only can build the specific model that the package is designed for?

I am looking for general parts to build different sorts of robots but I do not mind about electronic parts (motors, boards, sensors, etc. as I can build or buy those), I'm really after mechanical parts (gears, axles, beams, etc.).

I do not want pay for moulding and prefer to use something like LEGO parts, but I am unsure which LEGO set will offer the most flexibility to build anything I want?

Also if there are other universal building products other than LEGO that I could use I would be happy to know.

# Answer
Your question is not so clear, but it seems like you want to build robots and you want Technic pieces. Then Lego Mindstorms is the product you should buy. While not formally part of the Technic range, it contains only Technic elements in addition to the special electronic Mindstorms parts.

You can also take a look at Lego BOOST, a lightweight variant of Mindstorms, but that is not as much oriented around Technic pieces.

If you don't want the electronics, then you could consider the Bucket Excavator which contains a large number of elements for a fair price. Alternatively maybe you should also look at Meccano.
> 3 votes

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Tags: technic, building, robotic
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# Question
Title: How do I center a 2x2 plate on a 3x3 plate?
I want to be able to center a 2x2 plate in the middle of a 3x3 plate - specifically to put minifig on. Another option would be to center a 2x1 plate on a 3x1 plate.

# Answer
I saw this technique in LEGO's Disney Castle for offsetting parts of a column by half of a stud. You can see the column on the left in this picture is shifting half a stud above a 3x3 plate:

Of course you can do it too! Here is the process:

1. Take your 3x3 base plate and stick 1x1 "dots" between each of the studs. The "dots" are LEGO part 4073 which BrickLink calls "Plate, Round 1 x 1 Straight Side". So you end up with 4 dots on your 3x3 base. I didn't have a 3x3 handy so I start with a 4x4 to demonstrate:
2. Those dots form a new layer that is half of a stud off from the base plate (3x3 for the OP, 4x4 in the pictures). So you can just stick your next plate on it. (2x2 for the OP, 2x3 in the pictures)

# Addendum

A friend wanted to verify this and so we get to see the parts originally requested:
> 79 votes

# Answer
For centring a minifigure on a 3×3 plate, I would do the following (though it’s not exactly what you asked for):

1. Arrange 2×1 plates with centre studs as follows:
2. Add 1×1 panels for optical harmony:
3. Put a 3×2 plate on top:
4. Place your minifigure in the middle:
> 47 votes

# Answer
If stability is not an issue, consider the following:

1. Put a 4×4 dish on your 3×3 plate (yes, this fits):
2. Put your 2×2 plate in the middle (in any orientation you like):
3. If you want to centre your minifigure, add a layer of 2×1 plates with centre studs:

… and place your minifigure on top:

(This also works with a 1×1 plate instead of the dish, but it looks rather puny.)
> 18 votes

# Answer
Another soloution if rotational stability is not too much of a concern and you don't like having studs on show.

Put a 1x1 plate in the middle of the 3x3 plate and surround it with 1x1 or 1x2 flat tiles so you have a 3x3 surface with a single stud popping up in the middle.

You can now stack a 2x2 plate on top held in place by the single stud.
> 17 votes

# Answer
In 2017, LEGO introduced a new **1x3 Jumper plate (34103)**.

The first sets to include this piece are:

As of 2019 the piece is available in 10 colours in over 100 sets.

Hopefully in the future we can expect to see it in more sets with varying colours.

**Photo:**New Elementary (70620 NINJAGO CITY)
> 9 votes

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Tags: building
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# Question
Title: Problem with the range for controlling Sunset Cruiser 8676
Does anyone know why the Sunset Cruiser 8676 only works when the antennas are about 12" or closer together? Any farther apart and it doesn't run.

It has fresh batteries. Any help would be appreciated.

# Answer
> 3 votes
I had a 8378-1: Red Beast RC (which is practically the same hardware aside from running on a different frequency) that developed a similar problem shortly after I got it. One day the receiver only worked if the remote's antenna was about 2 inches away from the receiver's antenna.

I got it replaced, and it was indeed the receiver and not the remote with the problem. I later tried taking the busted one apart to see if it was something obvious I could re-connect, but nothing stood out as being broken.

Unfortunately, I think your problem is hardware failure. I don't know of any easy fixes, but would love to be proven wrong on that.

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Tags: remote-control
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title: NXT 1.0 software issue

text:
# Question
Title: NXT 1.0 software issue
I am an educator with 33 Mindstorm NXT 1.0 computers. We are a Mac school and are running El Capitan (OS 10.11). Two questions...

1. Is it possible to download the 1.0 software to our Macs? Has there been any update/upgrade to the 1.0 software?
2. I'm assuming I can't use 2.0 software with the 1.0 units correct?

# Answer
> 2 votes
I'm not sure about compatibility of different versions of NXT-G with different versions of macOS. However, regarding your second question:

The only difference between the 1.0, 2.0, and Education NXT kits is the parts and sensors that come in the kit. There is only one hardware revision of NXT brick, and any version of NXT-G will work with any NXT brick. Thus, if you found a version of NXT-G other than 1.0 that will run on El Capitan, you could use it program your NXT bricks.

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Tags: nxt, software
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# Question
Title: Why does my EV3 not have data logging in Brick App menu?
I recently purchased a 45544 Educator Mindstorms product. In working through tutorials. I am at section on data logging, but my Brick Apps menu stops at Brick Program. Data Logging is not on menu

My Brick Info is VO 60, FW V1.07H

# Answer
The brick currently has the "Home" version of the firmware loaded as indicated by the "H" in 1.07H. You can use the Education version of the desktop EV3 programming software to load the educational version of the firmware (ends in "E"). Data logging is only present in the educational version.
> 2 votes

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Tags: ev3
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# Question
Title: Does the Lego Mindstorms EV3 software work on macOS High Sierra?
Will there be issues with the software, or will it work properly on macOS High Sierra?

My Mac: Retina MacBook Pro 13", Early 2015

# Answer
> 0 votes
I've upgraded to High Sierra already. I just tried loading a large/complex program in the educational version of the EV3 software and sending it to the EV3 with both Bluetooth and USB. So, it looks like there are at least not any major issues.

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Tags: ev3, mindstorms, ev3-g, mac
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title: Uses for tracks in 9648

text:
# Question
Title: Uses for tracks in 9648
Has anyone used the Tank tracks (429139) from Lego education set 9648 for anything other than a tank?

The tracks are fixed in size, and I've found the application rather limited (driver belt, track) so far.

At this stage they seem to be a bit of a novelty - so any feedback welcome!

# Answer
My FIRST LEGO League team likes to use them as clothing accessories, like belts, headbands, sashes, etc.

More commonly, though, they are used for conveyor belts (for example, in a great ball contraption). You can also use them for a chain drive when 3711 is not strong enough or big enough.

I also saw this recently where small carriages were attached to the links and it was used as a vertical parking system for matchbox cars.
> 5 votes

# Answer
I think someone years ago use them for a machine gun design that actually worked, they placed shooting pieces upon the track and ran it through a special gear worked mechanism that pushed the triggers on top of individual shooters, I think it could fire over 500 a minute, not much of a range but it did look pretty good fun. (forbidden lego of course!)
> 1 votes

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Tags: nxt, technic, piece-information, sets, education
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# Question
Title: I need help identifying pieces, wooden cart, yellow cylinders, dark green cylinders, and white and blue rocket stickers?
These are only a small fraction of pieces that came in a large tote I purchased at a garage sale. I'd appreciate any help with identifying what they are and which set these go to.

# Answer
> 9 votes
Yellow half cylinders + White, yellow & grey assemblies are from:

8037-1: Anakin's Y-wing Starfighter

Dark grey part + dark green assemblies are from:

7930-1: Bounty Hunter Assault Gunship

White panels + light grey part + red / white striped part + cone & red 1x1's are from:

7593-1: Buzz's Star Command Spaceship

The cart is from:

7195-1: Ambush In Cairo

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Tags: piece-information, part-identification, set-identification
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# Question
Title: Are there any books on the history of economic, marketing and design choices of LEGO and the company?
I am interested in the history of economic, marketing and design choices made by the company, that shaped the product line (or individual sets) and the LEGO experience that we all love. Preferably about the post-2000 years.

# Answer
> 3 votes
Yes, there actually is a book that discusses just this subject AND it's primarily focused on the post-2000 years:

Brick by Brick: How LEGO Rewrote the Rules of Innovation and Conquered the Global Toy Industry by David Robertson.

I highly recommend this book - while professing to be a business book, it gives huge insight into the companies design-reasoning and history.

Amazon Link here.

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Tags: history, books
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# Question
Title: Which set are these bags from? Red bricks, grey plates, and yellow railings?
Can anyone help me identify which set these bags are from?

# Answer
These are from: 60110-1: Fire Station
> 4 votes

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Tags: set-identification
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# Question
Title: Does anyone know which set included a 2 piece moon?
I have a 2 piece moonlike miniset that apparently came included in some sort of larger space set. Anyone know what I'm talking about and where it comes from?

The collection includes a rocketship base with light-up and sound rockets. I assume its the same set as the moon. It's definitely not a Star Wars set.

# Answer
> 5 votes
Both the Countdown Corner and Mission Control sets included both a "Light and Sound" rocket and a multi-part "moon" in the form of the "Rock Arctic Globe":

# Answer
> 2 votes
If you mean something like this, a 11x11 ball

Then this link gives each pass and you can click through and find all the sets they came in https://www.bricklink.com/v2/search.page?q=Cylinder%20Hemisphere%2011%20x%2011#T=A

They have been used for moons, planets and a deathstar

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Tags: set-identification
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# Question
Title: How can I fix this gap in the Ghostbusters Firehouse roof?
We built the LEGO 75827 Ghostbusters Firehouse which was good fun. But despite being pretty sure we have all of the pieces where they are supposed to go, there is a gap in the roof:

Yet it goes into place with a slight push:

So:

* What could be causing this?
* How can I fix it without glue?

# Answer
I have this set and it does the same thing for me. The problem is that the size of the model and the tolerances between bricks add up and by the time you have a structure of that size not everything fits perfectly.

First thing you should do is make sure all the pieces are properly seated all the way down the construction of the model. It is possible to make the pieces rest in the proper position.

If that still doesn't work for you, you can certainly fix it by replacing some of the tiles with plates. The building is meant to be modular, and thus easily disassembled into sections, for play/display purposes. If you rebuild it with plates instead of tiles it will have more structural strength but will be more difficult to disassemble.
> 1 votes

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Tags: building
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# Question
Title: What are the holes on the backs of MegaBlocks Call of Duty characters for?
I need help with identifying this, and I'll have a lot more questions.

# Answer
The hole on the back of the figures is mostly used for backpacks and other accessories as shown here in the figure on the left:

In addition, it is also used sometimes to secure the figures into position. For example, in some open cockpit vehicles there is a peg at the back of the seats, that the hole on the back of the figures can attach to. This keeps the figures more secure in their position.
> 3 votes

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Tags: part-identification, minifigures, clone-brands
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# Question
Title: Which set is this bag from? It has mostly azure pieces
Can someone help me figure out which set this is from? Dated 2011.

# Answer
> 7 votes
This is a bag from Dimensions Starter Pack parts (71200).

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Tags: set-identification, lego-dimensions
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# Question
Title: What is the tiny-hand most-friendly sets to migrate from duplo to lego?
How do I migrate a kid who's taken an interest in lego (with a preference to minifigures) from their current duplo collection?

I'm tempted to buy just mini-figures, but have seen some "mini" sets that are mini-figure heavy like The LEGO® Batman Movie The Joker™ Balloon Escape: 70900 set. The problem is that these sets typically contain many small parts that is likely to get lost, or frustration ensues because building or taking them apart is difficult. (Funny enough minifigs aren't taken apart as you'd think...)

# Answer
As a conservative approach I would suggest the LEGO Juniors series which has cars and other sets and that are easy to build.

However, from first hand experience I can tell that kids learn quickly. Even if reading instructions is too difficult, playing with regular LEGO parts will soon be a lot of fun.

Besides : Losing small parts will be an issue with each and every LEGO set. Maybe you could consider buying used sets or even used bulk LEGO.

EDIT: LEGO Juniors is now called 4+, but it is the same product line.
> 12 votes

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Tags: minifigures, sets, shopping, duplo
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title: What set do these parts come from?

text:
# Question
Title: What set do these parts come from?
They are some of the most recognizable parts in a bag of a Lego set.

# Answer
As others have pointed out, none of this is LEGO.

It's Kre-o and Megabloks (LEGO clone brands)

Some parts are from Optimus Prime (30689)

The figures are probably Megabloks Halo
> 4 votes

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Tags: piece-information, clone-brands
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title: How to open Duplo train base 2961b?

text:
# Question
Title: How to open Duplo train base 2961b?
How can I open a Duplo train base 2961b without destroying it? It is not working despite fresh batteries. There are no screws.

# Answer
> 5 votes
This part wasn't meant to be taken apart, but it is possible.

Source with more text and images

also this (very dark) video tutorial

and another video tutorial

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Tags: duplo, repair, disassembly
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title: Programmable sound bricks

text:
# Question
Title: Programmable sound bricks
Regarding this component

It comes in several versions, each producing a different sound when pushing the button, e.g. a barking dog or doorbell. However, the sound is "fixed", is there any way to replace the sound with one of your own choosing?

# Answer
It can be programmed, but it requires specialized equipment

Here is one connected to a circuitboard

The external board is wired straight to the internal board. It plays the "doorbell then dog bark" sound from the brick in set 5771 - Hillside House.

Searching the number on the chip (39VF020) reveals it's a simple flash memory chip.

The board (AMA9AA) brings up pages from a Chinese company, Alpha Microelectronics, thatseems to specialize in voice/sound synthesizing hardware. There are references to software called EZSpeech and FlashWriter. There are download links for the software on their website, but they are password protected.

(by mpfirnhaber on Eurobricks)

This not LEGO related hobby store can make them with custom sounds TopdragonHK
> 2 votes

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Tags: customization
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# Question
Title: Is LEGO mindstorms good for a robot warrior or a small size soccer robot?
I want to know if I can build a warrior or small size soccer robot with LEGO parts? If not, are there any better options?

# Answer
> 2 votes
An option that comes to mind is building a Raspberry Pi-based robot. But it's not likely to be small nor easy to put together, code and all.

I think going for a LEGO robot would be easiest; motors, electronics and power source have all been taken care of. You "only" need to connect them and program the EV3 brick. There are numerous YouTube videos of Mindstorms soccer robots that can inspire you.

# Answer
> 1 votes
It's easy to use Lego Mindstorms EV3 to build small robots. There are competitions such as the WRO where EV3 soccer bots compete. Sensors like IR seekers from HiTechnic are used to detect the "football" which is an IR emitting ball. As for a warrior, it is hard to balance Lego robots to make something which can walk but you could make the warrior run on wheels or slightly complex quad-walker mechanisms.

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Tags: mindstorms, robotic
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# Question
Title: LEGO EV3 on Chromebooks not recognizing NXT bricks
I teach two LEGO robotics classes in middle school and in one of my classes I am using EV3 and in the other NXT. I was able to have these classes because of the Chromebook app, but the problem I am having is the EV3 Chromebook app is not recognizing the NXT's. Everywhere I read said they were compatible. Is there something I am missing?

# Answer
> 1 votes
NXTs require a special USB driver, which is only available for Windows and Mac, so programming NXTs with official LEGO software will only work with those platforms. (EV3's use a generic USB HID driver.)

Furthermore, using NXTs via Bluetooth is not supported in any of the official LEGO EV3 software products.

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Tags: ev3, mindstorms, nxt
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# Question
Title: What is the name of the small pins that are used with small wheels / rims?
I see that there are at least three different types of axles that can be used with LEGO wheels. I can name the first two — *Technic axle* and *Technic pin* — but I cannot name the third, which is like a Technic pin, but smaller.

Note that I've only seen it integrated into a larger part, such as a brick or plate, as shown in the image. I see that BrinkLink sometimes refers to parts like this as having "wheels holder" pins, but that seems to be a term that could apply to the first two types of axles as well.

Does a common and more precise name exist for this type of pin?

# Answer
> 6 votes
LEGO and others sometimes calls those pieces a "bearing element". This term however is not limited to just that axle.

LEGO's replacement parts service calls the holes they go into "HOLE Ø11" (possibly read "Hole Diameter 11"):

The width of the axle is roughly equivalent to the width of a "bar", like the 30374 piece used for Lightsabers as such.

None of these names are particularly satisfactory, but I'm not aware of any better names.

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Tags: piece-information, terminology, wheel
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# Question
Title: Programming/running a NXT brick with a dead screen, via PC?
I have a NXT set and the control brick has a dead screen. I tried fixing it (resoldered caps, ribbon rub, etc) to no avail. It's dead.

Is there any software that will allow me to program and execute code on the NXT brick without going through the screen options? Is there a way to see the screen on a PC?

# Answer
There is a tool called NeXTScreen that is available here that will let you see the screen (and remotely control the NXT). There are similar tools for OS X and Linux on the same page.

Once you have this setup, you should be able to use any programming environment that you like. The screen viewing programs should be able to run at the same time as anything else.

For example, you could use the screen viewing program to pair via Bluetooth, then program the NXT using NXT-G and use use the "run" button in NXT-G to start the program remotely.
> 4 votes

# Answer
My kids and I are having a blast controlling old NXT bricks with a few Android apps, via Bluetooth, and it all works like a charm!!! App links below:

I have 4 NXT bricks, but only one has a working screen. If you hold two units side-by-side, you can navigate to Bluetooth and enable. Or follow the steps below: Note: (Enter = orange button)

1. Turn on your NXT brick, "cool Mindstorm chime!!!"
2. Left button, (3) times, to "Bluetooth", press enter
3. Let button, (1) time, to Search, press enter
4. Searching.........let it ride for like (30) seconds
5. Press enter, to select your (one), Bluetooth enabled smartphone
6. Press enter again, to select slot one "cool passkey: chime"
7. Press enter once more, to select "1234" as your passkey
8. Finally, hop over to your smartphone & pair to "NXT" with that key

NXTpad: let's you see and execute programs on the brick, + more https://play.google.com/store/apps/details?id=appinventor.ai\_bccyuen.NXTPad

NXTremotecontrol: let's you control your builds like a TANK!!!! https://play.google.com/store/apps/details?id=org.jfedor.nxtremotecontrol
> 1 votes

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Tags: mindstorms, nxt
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# Question
Title: Why is there a hole in the large surf board (6075)?
Why does the large surf board (part 6075) have a large hole in it? The hole is larger than a normal stud. An example of this part is found in red in Coast Guard Starter set (60163):

Here's a closeup of the board so that you can specifically see the large hole that I'm asking about:

# Answer
This part is sometimes used to build a windsurfer as shown in Stephanie's Beach House:

The hole is larger than a stud because it is designed to receive a towball connection of some kind, usually a mast such as this one:
> 11 votes

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Tags: piece-information
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title: Lubricating 4.5V 6216m2 engine

text:
# Question
Title: Lubricating 4.5V 6216m2 engine
Is there any way to lubricate old 4.5V 6216m2 engines (these grey round ones)? I have 2 from my childhood, and they still run, but have trouble starting and make an awful 'whining' sound from time to time. I see no way to open them, and I haven't found anything through google about opening them. (I was hoping to see videos, but can't even find a text description...)

# Answer
> 4 votes
You don't need to open the motor to get the lubricant in. Electric motor oil is thin enough to work in if you hold the motor with the shaft uppermost and slowly rotate the shaft by hand while squirting a small amount down the shaft.

Don't use a lot - try a small amount, and see how well it works. Add more if needed.

(this one I found on Amazon)

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Tags: repair, motor
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# Question
Title: Lego Mindstorms EV3: programming language recommendation
I am planning to build an autonomous car in LEGO Mindstorms that will use ultrasonic or infrared sensors and in the future also a camera for line tracking. Currently I construct my programs using the Mindstorms building blocks, however, I am wondering whether I should switch to a different programming language such as C/C++ or Java to have more flexibility especially regarding lane tracking algorithms with the camera. In this regard I have the following questions:

1. In general, would you recommend switching to a normal programming language (I am quite "fluent" in languages like C/C++, Python and Java) in order to avoid having to use blocks when building more complex programs?
2. If so, which programming language would you recommend? I feel like there is a big community for leJOS and Java which is definitely a plus, although I could imagine that considering the fact that I would like to integrate a camera a language like C/C++ that works well with MATLAB or OpenCV for line tracking algorithms might also not be bad - what do you think would be the best idea for my use case?
3. Is it possible to use a different programming language without flashing my EV3 such that I can switch back to building blocks if I wanted to?

Thank you for your recommendations!

# Answer
> 8 votes
> 1. In general, would you recommend switching to a normal programming language (I am quite "fluent" in languages like C/C++, Python and Java) in order to avoid having to use blocks when building more complex programs?

Yes, especially if you plan on doing image processing.

> 2. If so, which programming language would you recommend? I feel like there is a big community for leJOS and Java which is definitely a plus, although I could imagine that considering the fact that I would like to integrate a camera a language like C/C++ that works well with MATLAB or OpenCV for line tracking algorithms might also not be bad - what do you think would be the best idea for my use case?

I'd recommend using ev3dev, as it seems more-powerful and leJOS development appears inactive.

ev3dev has a few languages you can chose from, though your choice may be limited somewhat by which languages support the image processing libraries you want to use.

> 3. Is it possible to use a different programming language without flashing my EV3 such that I can switch back to building blocks if I wanted to?

With ev3dev, you run the software off a removable micro SD card. No need to replace the internal firmware.

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Tags: ev3, mindstorms, nxt, ev3-g, ev3dev
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# Question
Title: Looking for a list of Star Wars minifigures
I just started a collection of minifigures of LEGO but exclusively of Star Wars (Although also I include some monster, like the dewack), so my question is simple.

How or where can I get a list of minifigures that currently exist?

Is it something that can be obtained or are simply guided by other things to have these collections?

# Answer
> 4 votes
BrickLink is your friend. Use the Catalog Search function to find all Star Wars related minifigures ever produced (all 896 of them as per today). Clicking on each minifig gives you the set(s) it came in.

Here are the results if you search for Type = Minifig, Theme = Star Wars, ordered by year of release: http://www.bricklink.com/catalogList.asp?v=5&pg=1&catLike=W&catType=M&catID=65

# Answer
> 1 votes
The most complete list there is - www.minifigs.nl \- His database is jaw-dropping and always up-to-date.

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Tags: minifigures, star-wars
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title: Authentic or Not?

text:
# Question
Title: Authentic or Not?
I browse periodically on eBay and see a lot of superhero lego minfigs. Are these real or Chinese knockoffs? It says that they're from China. I just search "lego minifigures".

http://www.ebay.com/itm/8-Sets-Super-Heroes-Building-Toys-Flash-Cyclops-Catwoman-Minifigures-Blocks-Toy-/141294442500?pt=Building\_Toys\_US&hash=item20e5ce1804

# Answer
They are fakes. From China. Some people do buy these as they are significantly cheaper than LEGO's version, however there are also problems. The quality varies greatly with some figures almost as good as LEGO, while others won't even fit together properly (see the close-up pictures in the auction). Also, the print rubs off of them quite easily. If you are just planning to buy them for a child who doesn't care about quality they are good alternatives. However they are not suitable for collectors. Also, consider the implications of ripping off both LEGO and Marvel/DC Comic licenses.
> 5 votes

# Answer
They are knockoffs, I have ordered superhero minifigs, as well as bulk minifigs, from Ebay and they are definitely fake. That is not to say they were terrible quality(although some were) but you can tell by the way they fit together they knockoffs. The paint, ease of attachment, and sometimes the overall design is a dead giveaway.
> 1 votes

# Answer
If the brand is not mentioned and the country of origin is China, you can be 99.9% certain that it's not LEGO but Lepin, Duo Le Pin, Kazi, XingBao or one of the many other Chinese brands.
> 1 votes

# Answer
Definitely look like knock-offs to me. The plastic just doesn't look quite right, even down to the reflections. I'd be concerned about buying knock-off LEGOs for a child - you have no way of knowing whether the materials used in the construction is safe, and also high risk of bits snapping off. (although that's probably true for LEGO in general).
> 0 votes

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Tags: minifigures
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# Question
Title: How to power up MOC-0308, based on Technic 8297 Off-Roader?
I have built the following MOC, with details here and here.

It is pretty complete, although I would have tried some servo motor for steering.

But after I've finished it, I've got into trouble:

1. Wheels on one side of the car seem to work sporadically. Could this be related to the steering joint and Cardan joint below?

Or the differentials?

(image taken from Is it possible to create a differential if I don't have it as a ready to use element?)

2. It's too weak.

A wool carpet of 2cm thick is an insurmountable problem for the car to climb on it and go, especially for the last wheel or pair of wheels that have to pass the carpet's border (and difference in level), regardless which ones have to do it (back or front).

Are there too many differentials? Too many tooth gears? Too much elastic parts to deal with the torque? I can't find parts blocked.

The driving ring 2L, , at the page 28 of the building instructions, should act as differential to switch between 2 x 4 and 4 x 4.

Could it be a defective motor? Is one XL motor too weak? Would be more powerful with two motors (in the back)? Which kind?

Batteries are OK for 9398, so it's not them.

Did anybody tried this MOC?

Sorry to have too much questions, it seems I need more experience with LEGO Technic.

**UPDATE**

I have changed it consistently, adding a gear down for each wheel (horizontally) and that made it 4L longer.

Also, moved the steering motor in front and the up/down and winch motor in the middle (switched their places), using a servo for steering.

As result, it is a bit more powerful, it climbs the carpet now, but I need to work more on the steering because it is not that smooth when it comes back in the default position. 9398 is better at going back to the default steering position. Also, 9398 is more powerful as it gears down 3 times instead of one.

Overall, the new design feels better, yet too lazy.

# Answer
> -2 votes
The piece you show must have steering axle 92906.

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Tags: power-functions, moc
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