# Question
Title: Is it worth to start with Dimensions now?
From what I know Lego will cancel the Dimensions game soon. Right now it is possible to find on ebay very cheap starter kits. Is it still possible to play the game after Lego is closing down all activities or is a Lego server essential for the game functionalities?

# Answer
> 3 votes
The Lego Dimensions game is actually a console game available on the PlayStation 4, Xbox One, Xbox 360, Wii U, PlayStation 3. So as Shea stated, once you have the game, you can play it whenever you want. All you have to do is insert the disc into your console and load up the game.

About your concern of buying the starter kits, getting the one on eBay could be a choice, as long as you trust the seller. Another way is to get it at Target or Walmart before they don't sell it anymore. Another suggestion for you is to get all the current available sets for Lego Dimensions that are available in store, as once they are no longer being sold at stores, the value will skyrocket. After you have gotten the desired in store sets would you then get it off eBay.

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Tags: lego-dimensions
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title: Need help identifying sets!

text:
# Question
Title: Need help identifying sets!
So...my son is 9 years old. Up until this year, he has been receiving Lego sets since he was about 6 but would rip them open, build the guys and then not finish the set. Now he is really unto them finally and I'm trying to piece back together his older sets so he can finish them. Alot of them are still in bags but some aren't. I'm going to post pics of the intact bags I have and would love help identifying them so I can try to find the instructions instead of throwing away tons of $$$. All of them are newer than 5 years...I have a couple that are mega blox and will post those too

# Answer
> 3 votes
Last photo unnumbered bag: 76037-1: Rhino and Sandman Super Villain Team-up

# Answer
> 2 votes
Image 3 is also pointing to Minecraft. I focused on a "specific" piece which is part 6089103 and result being an arc. It's contained in 12 sets.

Then combining with the basic 2\*4 orange brick, we got 7 sets.

I found these instructions for bag 5 (page 2), and seems to be the one (has the skeleton arms, the single round grey parts, orange/blue brick in it...)

So I'd tend to say that's 21118-1: The Mine Check the instructions maybe others bags can match that box.

@Phil B. tends also to say that the 6th image is from that set.

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Tags: piece-information, set-identification, set-database
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# Question
Title: Do we need WiFi Dongle to install Scratch on EV3
I was wondering if I can install Scratch program on EV3 brick without the wifi dongle.

Appreciate any insight here.

# Answer
> 1 votes
No. Bluetooth on the computer you are using is necessary but you don't need a wifi dongle for either your computer or the ev3. If you are using the EV3+Scratch extension on scratchx.org, all you need is the scratch x plugin and a computer with Bluetooth (or a bluetooth dongle).

Here is a good article about how to set everything up.

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Tags: ev3, wi-fi, scratch
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title: Utility pole and angles

text:
# Question
Title: Utility pole and angles
I am using the following MOC from the Internet:

http://www.moc-pages.com/moc.php/8435

This model is fine if the sets of power lines are all in a straight row. But what about at an angle? How does the model need to be adjusted if the lines meet at, for instance, a 90 degree angle? 45 degrees? Thanks.

# Answer
> 5 votes
The pole itself can be rotated on almost every level, so that’s nothing you need to worry about.

Additionally, you may want your cables to be parallel. To achieve this, you need to increase the width of your bars, or more specifically, the distance between the cable supporters. If your distance between the supporters for a straight line is *d* and you want an angle of *θ,* you need a distance of *d*/cos(*θ*/2) at the angle, which can be obtained using trigonometry:

So, for an angle of *θ*=45°, you need to increase your distance by a factor of 1.08. For *θ*=90°, it’s a factor of √2 = 1.41.

The obvious items to adjust the distance are 1×1 round bricks and plates. Also, you obviously can only approximate the perfect distance with bricks in most cases, but the inaccuracy will be negligible.

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Tags: moc
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# Question
Title: Why won't the loop block in my EV3 program stop?
I am building a robotic hand, and I programmed the finger to close when the touch sensor is pressed, and release when the touch sensor is released. It did that with a loop block -

but when I ran this the finger kept holding down. I could tell because when I tried to gently tug on the motor, it wouldn't budge.

Can anybody tell me what's going on?

# Answer
> 3 votes
Your code instructs the motor to continuously turn in one direction, and because you chose a motor block in the “on” mode, it will continue to turn even during the loop condition check. The loop condition says the loop will continue as long as the button is released (AFAIK, I don’t have an EV3 close by currently to validate this), which means that it does exactly the opposite of what you intended. Change the loop condition to loop as long as the touch sensor is pressed and you will fix this issue. Plus, once the loop finishes, the motor will still continue to turn; you would need to put a Motor block in the “off” mode directly after the loop.

# Answer
> 0 votes
What your current code does is to keep closing the finger until you press the sensor. This code may help.

You might need to change the 180 degrees boxes according to how many degrees the motor has to turn to close the finger.

# Answer
> 0 votes
You need to stop the motor after the loop

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Tags: ev3, motor
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# Question
Title: Are there any wheels or rings that fit in pin clips?
I was experimenting with Lego part 16091 Vehicle Steering Wheel Small and various clips, mainly the ones that fit onto bars. To my frustration I found that the clips do not engage at all with the ring that forms the wheel’s circumference; they fall right off.

So my question is this: are there any similar parts (wheels, rings) that do engage with clips in this way?

# Answer
The small Technic Steering Wheel and what I think is this rubber belt connect to clips:
> 6 votes

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Tags: building, moc, wheel
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# Question
Title: How should I get started with LEGO trains?
I'd like to get started with LEGO Train. I understand the PF system is The Way, and the tracks are generally mutually compatible, but the exact interplay of trains & power components eludes me.

Is there a "Just the train, PF control system, and tracks" set available? Would that be set 60051?

# Answer
That set would work, set 60052 would work as well (although it has a few more parts that are not actually needed if you are really focused on trains, in that regard 60098 might be better)

Those sets (including 60051) are from 2014/2015, rumours have it that new trains will come out this year (probably around august), and apparently (I hadn't heard it before @TheBrickBlogger wrote it in a comment here) they won't be completely compatible.
> 2 votes

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Tags: trains, power-functions
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# Question
Title: Why is LEGO kit name not on the box or booklet?
Curious to know why LEGO set boxes and instruction booklets carry a number and age recommendation (Eg 7-12 41317), but not any marketing name (Sunshine Catamaran)?

To get the name, I need to visit an online store selling the kit to get the actual name of it. Not sure if this is just an Australian marketing practise but curious as to why this is so - I find it frustrating.

# Answer
> 7 votes
Most-likely it has to do with localization.

If they printed the names of sets on instructions, they would have to print a different instruction booklet for each language the set name is translated into, in addition to translating the boxes (and possibly the stickers).

You will notice that instruction manuals are usually free of any written instructions, which would need to be translated, and instead opt for imagery when possible. If they do have substantial text, it is usually translated into a number of languages, like the game rules in the back of the manuals for the large Orient Expedition sets had.

Of course, simple things like "Click" get a pass on translation.

Sets whose name would not change if localized sometimes have names printed on their instructions though.

# Answer
> 3 votes
It's more complicated than that. In some markets boxes do carry the set's name. I just took a picture of two sets I have lying around unopened:

As you can see the elves set in front has the name on the box, while the Disney princesses set in the back doesn't.

I don't precisely remember where I bought those two sets (but it's not unlikely one was intended for sale abroad), but I suspect it has to do with what markets they were intended for. It's probably relatively expensive to have boxes printed with the danish name (I'm from Denmark) as they would basicaly only be usable in Denmark,while boxes with the english name are far more usable. But as you speak english in Australia, and you say you see boxes without names on them, that can't be all.

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Tags: manufacturing, disney
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# Question
Title: The route a power line takes through a neighborhood
I have a small Lego town built. I want to add power lines. However, I don't know how to route the power lines through the neighborhood. Should I create one line that snakes between all the houses? More than one line that take separate routes? Why do utility poles have so many lines on them in real life? Thanks!

# Answer
As seen on your question about angles generally the connection from the power line to the house goes via either a Distribution Transformer (the grey cylinders in your image) where the power lines are run at a much higher voltage than domestic use and then either down the pole, into the ground for local delivery to the house or directly to the house.

In terms of how many lines and paths - I'd start from your primary sub-station where the main power lines come in and radiate out from there - initially with four lines, and then stepping down to two about half-way to two thirds out - effectively the lines are running in parallel, with each house drawing off their usage as it goes, so you'll see some drop off.

Depending on the final scale, more than four lines might look cluttered, whereas two will convey the impression of power nicely even if it's not physically accurate (a nice compromise might be three, with the third line running on top of the poles).
> 2 votes

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Tags: moc, electronics
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# Question
Title: The route of a major power line with branching smaller lines
In this discussion I was shown a diagram of how to bend a single power line around a street corner.

However, what if I have a straight major line with several minor lines branching off at right angles? How do I build/orient the utility poles in these cases? Thanks.

# Answer
The first photo in the Wikipedia entry for "utility pole" shows additional horizontal bars for the respective branches. Single lines are attached directly to the main pole. I think on this scale you don't have to worry about how realistic the setup is (i.e. how the branching lines are connected to the main lines, how the transformers are connected, etc.).
> 3 votes

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Tags: moc
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# Question
Title: Principles of D.I.Y. Minecraft microworlds
Lego released 4 Minecraft microworlds which more or less fit together with each other in some meaningful way.

Just to impress my boys I've been making my own worlds on 6x6 plates or wing pieces. I've only got two sets (The Forest and the Nether) so I can't see too much of a theme between them.

If I wanted to make a really big Minecraft mini-world, what principles would I employ to construct each of the cells?

# Answer
> 3 votes
There are two key ways these can "fit together":

1. Most obviously by size and connectors - all the worlds are built on 4 6x6 plates, and have a 1x2 with cross-hole brick at the bottom in the centre of at least two sides.
2. By theme (or in Minecraft terminology "biome") and features (forest, mountains, etc).

In terms of the four sets released, only two meet both of those:

* The Village
* The Forest (Ideas)

These both use the same shades of grey for the underground sections, and similar colours for the overground sections (greens, browns, etc.).

The other two sets represent completely different areas ("dimensions") within Minecraft accessed via special portals - there's no way to walk from a Forest biome to The End or Nether, so from a connecting point of view, neither of these really "connect" to the others.

So to create your own cells you'd want to follow the following guidelines:

1. Choose a Dimension (Overworld, Nether, End)
2. Work with 6x6 plates (or variants/multiples of)
3. Use a scale of 1x1x2/3 for most blocks (i.e. 2 stacked 1x1 plates) which can be capped with a 1x1 tile, for deep sections bricks can be used
4. Underground is typically 4 bricks tall, overground can be taller
5. Transition between biomes nicely (Forest - Beach, Forest - Jungle, etc.)

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Tags: building
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# Question
Title: I'm missing a few pieces in my XingBao set
I just finished the second floor of XingBao's 5052 piece Maritime Museum.

And while I'm pretty impressed with the overall quality of the building, I thusfar am missing 4 parts.

Is there a way I can obtain substitutes from XingBao for the missing parts?

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### Note

The set I'm refering to is NOT a clone of a Lego product or fan-built MOC but an original MOC created by XingBao's YiyiToys design team. Unlike Lepin, which is infamous in the Lego community for blatantly cloning Lego sets, XingBao's sets are all original designs and not Lego clones.

# Answer
Xingbao reproduces standard LEGO elements for their models, so it should be much easier to replace the missing parts with LEGO pieces, then trying to contact Xingbao. If you are not familiar with the LEGO equivalent of the missing parts, you can post a picture here, and the community here should be able to identify them for you.
> 4 votes

# Answer
Apart from the fact that with this purchase you sponsored an IP-violating product and made yourself complicit to illegal activities, one of the other downsides of buying unauthorized clone copies is that customer service is non existing. You can buy the missing pieces on BrickLink or from LEGO’s Bricks&Pieces service, provided these are just clone copies of proper, existing LEGO bricks.

I doubt you will find much support on this site for your purchase, however, and many will perceive the omission of pieces as a rightful punishment for supporting these companies.
> -1 votes

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Tags: sets, clone-brands, replacement-parts, modular-buildings
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# Question
Title: Are there any good Brick Labels out there?
While resorting my large quantity of LEGO bricks, I was wondering if someone had created a library or file that included labels that could be placed on the outside of containers for a large number of common and not-so-common LEGO bricks. They would just need to contain a picture and the part number of the brick at the least, but one that includes the names would be great too!

# Answer
> 9 votes
Brick Architect has labels available for printing. These are designed to be used with a label maker, but there are also full page PDFs available that can be cut out. Here's an example of how they look:

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Tags: part-identification, organisation
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# Question
Title: Why am I required to buy something on BrickLink before I am allowed to sell?
Why does BrickLink require you to purchase something before you are able to sell? I already have too many Lego bricks and I'm trying to get rid of a lot of them, so I'm not trying to buy more. I'm just trying to sell all the characters I have, but it won't let me.

Why is this policy in place?

# Answer
> 6 votes
It’s not perfect, but it’s their way of finding reputable sellers. Any purchase counts so you can just buy 5 more cheap minifigs.

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Tags: bricklink
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# Question
Title: How easy is it to sell on BrickLink as a non-dealer?
I have been looking at a few of my old LEGO sets on BrickLink and they seem to sell for a lot ($500-$1000) - the information also suggests they actually are being sold periodically.

However, I've never sold on there before. I know that with most sites like that (Ebay, etc) it's really hard to sell without any reviews/feedback and particularly for expensive items.

Is this something which is even reasonable for me to even attempt to sell on BrickLink?

# Answer
In general, it is considered best to first build up a reputation (i.e. feedback) by selling smaller items, before offering up rare and expensive items. When a new seller (low or zero feedback) offers up an expensive set, the following might happen:

1. Buyers will be afraid to purchase from you as offering expensive sets for sale by low feedback buyers is associated with scams.
2. You expose yourself to fraudulent buyers who are preying on new seller and try to pull a fast one (e.g. claiming something never arrived, or claiming something arrived damaged, or even returning something opened and replaced).

This is not to say that those things will always happen, but low feedback raises warning flags.

Of course, with proper research and careful shipping you can avoid all of this, and especially if you are competitively priced you might sell sooner rather than later.

Being perceived as a scammer, or being scammed yourself, is something that is unfortunately a regular phenomenon on any marketplace, be it Amazon, EBay, BrickLink or Craigslist.

So net, just be careful and do proper research on how to best cover yourself against potential scams. Selling LEGO can be a very exhilarating experience!
> 5 votes

# Answer
In my opinion, I don't really like the way Bricklink is set up for sellers and actually think eBay is much easier. On eBay, you are able to start selling right away but with Bricklink they require you to make a purchase first, Which I think is ridiculous. If anything I would probably suggest to use Bricklink to get an idea of the price and then go sell it on eBay. At least that's what I am doing. Hope this helps.
> 1 votes

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Tags: shopping, bricklink
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title: Are these round black 1x1 pieces LEGO?

text:
# Question
Title: Are these round black 1x1 pieces LEGO?
A friend encountered two pieces of plastic in a bulk lot of LEGO she bought and was wandering if they were actually LEGO, a clone/custom brand or something else entirely... She sent the following pictures:

There are no markings or numbers on the pieces. They do seem to fit on LEGO studs:

I don't recognize the pieces so I assume they aren't LEGO. But perhaps someone here can identify them?

# Answer
> 14 votes
These are Lego parts.

The part on the left is a hose end (752). It is found on the ends of hoses like this:

The one on the right is 6221 (Peeron 424).

This part was most commonly found in older Technic sets as a spacer or crank handle:

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Tags: piece-information, part-identification
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# Question
Title: Is the Lego Duplo Track System being discontinued?
Our child recently got the Duplo train starter set 10507 as a gift. The box indicates an extension pack with more tracks, so I was confident our child would be able to extend the (sorry) somewhat boring little circle out of 12 curved track parts from 10507.

On the official Lego website, however, I am seeing now that the only two Duplo train sets still being offered now are the aforementioned 10507, as well as 10508, the huge Deluxe Train Set, as well as 10810, a push-train.

With 10507 and 10508 having appeared in 2013, only 10810 having been released in 2016 (and this set being rather "simple" - no motor, no switches, also just one straight track per set), and the latest tracks pack, 10506, not even available any more in the official store ... **does this mean I should start hoarding compatible Duplo tracks now, before I also can't get any on Amazon and in toy stores, either?**

*Note that I'm not asking whether anyone can see the future. I'm asking whether TLC has made any public announcements on their future plans for Duplo railroads, or whether there are at least any known sales numbers for Duplo railroad sets that indicate they are/are not a commercial failure these days.*

# Answer
> 8 votes
It hasn't been officially announced yet, but there are at least four large LEGO DUPLO train sets coming this summer. This includes two extension train track packs with straight tracks, curved tracks, switches, bridges, and train crossings. The two full train sets will include more of the same tracks. The set numbers for the extension packs are #10872 and #10882, and the new train sets are #10874 and #10875. The official set names are prices are yet unknown. I would suggest to wait until the summer, unless you can get the older sets for a very good price.

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Tags: duplo, discontinued, tracks
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title: Build-A-Bricks Building Set

text:
# Question
Title: Build-A-Bricks Building Set
When I was a boy - 1940's-50's - I had a plastic building set called, Build-A-Bricks, or some such. It was for modeling brick houses. The pieces were similar to LEGO but larger and there were cardboard windows, doors and roof elements. Does anyone remember such a product? Are there any such products on the market now?

# Answer
> 5 votes
Yes, maybe called Bilda-Brix.

I was given set for Christmas when I was 4.5. This would have to have been 1951.

Don’t remember any instructions, just used my imagination to build houses, towns and even battle ships! They were mostly red, some white hence I could have opposing battle ships. LEGO with its kits to build a specific thing has always seemed to me to demand less of the imagination.

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Tags: building, clone-brands
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# Question
Title: LEGO twin-engine airplane (black/yellow/grey) set identification please
Bought this airplane "as is" at a flea market. Pieces missing. I want to repair it. Does anyone here have the LEGO set number or know where I can find the instructions ? I suspect that it is several years old (1980s ? 1990s ?).

# Answer
> 6 votes
This is set 8425 (quite a nice set imho) and the instructions are downloadable from lego themselves: https://www.lego.com/biassets/bi/4101173.pdf The set is from 1996

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Tags: technic, set-identification, vehicle
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# Question
Title: LEGO MINDSTORMS EV3 Can't find MyData Block
While going through the challenges of the Gyro Sensor Investigation I came upon the issue that I do not have the MyData Block (It's a dark blue block with a graph on it) on the coding program. Could someone include the download for this block or assist me in retrieving it?

# Answer
EV3 software comes in two varieties, Educational and Home. The Educational version has a few blocks that do data operations that make sense in a science class.

Both versions are downloadable from Lego for free.

I think the MyData block is actually the data logging block. It looks like this:

To get this block for use in your programs, you would need to download and install the Education version of Mindstorms.
> 4 votes

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Tags: ev3, mindstorms, programming, lego-games
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title: How to sell a large amount of Lego

text:
# Question
Title: How to sell a large amount of Lego
Hope someone can help. I bought my husband a huge bundle of Lego a few years ago, but he doesn't have the time to sort it, so we want to sell it on.

We've identified a lot of the sets from pieces/minifigs/searching Google images for instruction books etc.

It's a mix of mainly Star Wars & Harry Potter. Loads of mini figures, no idea if the sets are complete. I don't think the HP is.

What's the best way to sell it? I really don't want to split it, thought about eBay, but as I don't know how much is complete I don't want to end up in a dispute.

Any info would be great! Thanks!

# Answer
> 11 votes
Since you don't want to go through the trouble of sorting the bulk lot, you can sell it as is either locally or at an auction site like eBay. It is perfectly normal to sell bulk lots of LEGO both locally and online without being able to tell exactly what's in the lot. If you want to spend the least amount of time on this, I would suggest first listing the lot on Craigslist or similar venues you may have locally. If it doesn't sell locally within a month or so, put the lot up on eBay.

Whether you sell locally or through an auction site, describe the lot as much as you can, but don't make guarantees. Just describe what you see. If you have a scale, measure the weight of the loose LEGO pieces. Many people buy LEGO by the pound, and knowing that the lot includes i.e. 10 pounds of pieces can be helpful for buyers to understand what they are looking at. (Just for your information, $5/lbs is the usual going price for mixed lot of used LEGO that buyers are willing to pay).

You can sell the lot just by a brief description, the weight, and pictures. It is a normal and accepted practice to sell mixed lots of bulk LEGO. However, if you spend a bit more time on the description, you will likely get better offers. This would include things like the general condition of the pieces, instructions and minifigures. Are there any other toys or foreign objects mixed in? Do the pieces need cleaning? Do they appear lightly used or heavily played with? Are printed pieces and clear pieces scratched up or appear to be in good condition?

If you feel they may have special value, describe the minifigs separately. How many there are, and what is their condition. If you see teeth-marks, paint marks, stains, missing body parts, etc. the value is going to be a lot less then if they are in pristine condition. Again, don't make guarantees, because everyone will have different standards, but just describe what you see.

Include a list of the instruction booklets. List the set numbers printed at the front of the instructions, as well as the condition of the instructions (i.e. missing pages, ripped pages, other damage). The list can give people an idea what pieces might be in the lot.

Whether you advertise locally or through an auction site like eBay, one of the most important part of your description is pictures. The more detailed pictures you take, the better. This doesn't mean having to photograph every piece separately, but just spread out the pieces as reasonably as you can and take good quality shots. You might want to also take separate pictures of the minifigs and the instruction booklets. Make sure that the pictures are not fuzzy and dark. The more people can see, the better their offers are going to be.

If you list on Craigslist or a similar local site, you will need to put a price on the lot. This is a bit tricky as you don't want to ask for something outrageous to put off people from even contacting you, but you also don't want to lowball yourself. You could work with the $5/pound standard for bulk lots, and maybe ask for $7/pound, leaving some room to go lower if necessary. eBay is a lot easier in regards to pricing, as the market will give you exactly what the lot is worth based on your description and pictures. List the lot as an auction with a low starting price and/or reserve, and let people bid what they think the lot is worth. Keep in mind that eBay will take 10% of the proceeds, and another 3% will go to PayPal.

If you sell through eBay, you will also need to ship the lot to the buyer. Get the right size shipping box and packing materials beforehand so you get at least a rough idea of how much it is going to cost to ship. Pack smaller lots into Ziplock bags before placing them in the shipping box. This will prevent the pieces from rattling around too much and getting damaged, and it also prevents bringing attention to the content of the box (stealing boxes full of LEGO is pretty common). You can offer free shipping (this will bring in more potential bidders, but you will have to eat the cost yourself), or let the buyer pay for shipping. The eBay selling platform helps you set this all up.

Keep in mind that selling the lot bulk is still going to bring in the least amount of money. This is understandable, as people are talking the risk of not knowing what's exactly in the lot, the condition of the pieces, minifigs and instructions, and how many of the sets are complete.

Another option you might consider is hire someone locally to sort the pieces for you into sets that you can then sell separately. You might not have the time and inclination, but many people love to sort LEGO. You can even have a sorting party with a few older kids and/or adults. Offer some pizza and drinks and they will be happy to sort the pieces for you into sets. Once the sets are sorted, depending on how complete they are, you can either sell them as complete used sets, partial used sets, or smaller bulk lots of Star Wars sets, Harry Potter sets, etc.

One last thing I would add is that LEGO is bringing back Harry Potter this year. They will likely have much better sets and minifigs than in the past. If you want to sell the lot you have for the best price, I would suggest doing it before the new sets are released.

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Tags: shopping, star-wars
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title: Please identify these sub assemblies

text:
# Question
Title: Please identify these sub assemblies
I got these assemblies and I am trying to figure out if they are MOCs or part of a set or sets. The little figure that has the clown inside has a part with a decal of "spirit of luis", but this only appears in 7307 so it might be a MOC. What about the rest.

# Answer
> 9 votes
The wing and red cockpit are from 9497-1: Republic Striker-class Starfighter

# Answer
> 7 votes
The little build in the bottom left corner is part of set 8897 Jagged Jaws Reef.

# Answer
> 7 votes
I found by accident that the bike is the 2259 Skull Motorbike, but partially built and modified.

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Tags: set-identification
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title: What is the Travis Brick?

text:
# Question
Title: What is the Travis Brick?
This question uses the term "Travis Brick", but I've never heard it before. What is it, and where does the term come from?

# Answer
> 18 votes
The Travis Brick is the 1×1 brick with studs on four sides.

The nickname arose amongst LEGO Space builders. It was nicknamed The Travis after talented Space builder Travis Kunce. He liked the part so much he had a tattoo of it.

The brick is especially useful in SNOT techniques as it has studs on all but the bottom surface.

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Tags: piece-information, terminology
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# Question
Title: How to pause, and restart (without resetting), a timer block - ev3
We're trying to pause the timer block, and then have it restart at the same time where it left off.

By using the touch sensor in a loop before our timer code we were able to get the text output to stop and restart, however on restart the text output just jumps to the current timer output, so it's clear we're not actually pausing the timer output.

Any ideas on how to pause and restart the timer block using the touch sensor?

Here's our code:

# Answer
> 4 votes
I don't think there is a shortcut. The timer sensors record how much time has elapsed since they were reset. The starting of the program gives you the first reset for free. So the psuedocode ends up something like this. The button touched vs released is a personal preference. I think of the interval as starting when the button is released and extending until it is pressed.

* Set a variable "totalTime" to zero
* Loop start
* wait for button touched
* Set a variable "intervalTime" = timer sensor value
* Set "totalTime" = "intervalTime" + "totalTime"
* Set intervalTime = 0
* wait for button to be released
* write to the LCD display "ready for next interval"
* wait for button to be touched
* wait for button to be released
* reset the timer sensor
* Loop end (forever)

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Tags: ev3
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# Question
Title: Did these random parts come from a set? Dark grey, dark green, and black turntable
Here is a random half made LEGO creation which I bought within a large bag of LEGO. Do you have any ideas what it could be part of?

It is so frustrating trying to identify, but I'm excited at its prospects! If anyone has any tips on how I can figure this out myself that would be appreciated too.

# Answer
> 5 votes
This assembly comes from the Lego Set 76008 Iron Man vs. The Mandarin: Ultimate Showdown.

The assembly can be clearly identified on steps 14, 15 and 16 of the instructions available for example on BrickInstructions.com.

Here is how I proceeded to identify the set:

1. Spot any less common part (brick type & color), here the *Slope 18 2 x 1 x 2/3 with 4 Slots* in dark green color.
2. Use the BrickLink parts catalogue to look for all sets where that brick is used. Results here.
3. For each dark green entry, look at the set inventory and try to spot additional less common parts. In this case, I was trying to find the 4x4 black turntable plate.
4. Increase your level of confidence by matching a couple more bricks. The unique 2x4 red brick from the inventory was a good match as well.
5. Confirm the identification by finding the assembly by browsing the set instructions.

---
Tags: part-identification, set-identification
---


# Question
Title: How do I sell complete LEGO sets still assembled?
I have several complete items I want to sell. I have the instruction manuals but no boxes. They are still together. They include the old Death Star, and some other Star Wars, the complete Lone Ranger set and more. How do I do this?

# Answer
You can list the on BrickLink as complete, used, no box. Those are options you can select as you list each set. You can also list them on eBay, and just put in the description that the sets are without box, but with instructions and all the pieces included. This is a normal and accepted way of selling LEGO sets.
> 2 votes

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Tags: shopping, disassembly
---


# Question
Title: Find out the set(s) a list of parts belongs to?
I have gotten some help here before regarding set identifications. I now need to find the set some parts belong to. I know how to find this per piece, but i need to search with a list instead. Reason is that a part may belong to 100 sets, and another part may belong to 200 sets, together though may appear in a few sets. This process would get much easier to a solution.

Thanks

# Answer
> 2 votes
I would use the rebrickable website for this:

* create a custom list (type to build)
* browse for the parts and add them to your custom list
* go to the custom list
* select Built this List
* go to the Suggested sets tab.

However, this amount of effort is normally not necessary to identify a set, there is nearly always a less common element in your list and bricklink can be used to list the sets having this element, narrow down manually with the second less common element, etc...

---
Tags: piece-information
---


# Question
Title: Where do I find thousands of blue & yellow bricks for an art project?
I'm an artist and I've started a project where I need around 4000 blue and yellow bricks, specifically bricks and plates that are 2x or 1x any length, but the longer the better. Any suggestions on where to find these for the best possible price?

NOTE: I've purchased several used bulk lots on eBay, but on a price per brick I need basis, this isn't very cost effective. I've also gone to the LEGO store, but I you really can't get many larger bricks in those little cups, plus I actually prefer the look of used bricks. Any suggestions would be really appreciated. I don't have a lot of money as I'm a college professor, but I am having my first solo museum exhibition next fall and I'd really like to include this piece. (Sadly, unless you're world famous, museums don't pay a penny for artists materials.)

# Answer
Try BrickLink.com, the Online LEGO Marketplace. It works like eBay, with buyers and sellers from all over the world. You can buy the exact pieces you need, in the quantity and condition you need.

Since you want a large bulk of parts, I would suggest that you post your request on the BrickLink Forum first, as there may be sellers who have a very large quantity of what you want, but haven't listed in their stores (sellers like to focus on listing their more expensive stock first).

Most BrickLink sellers are good people and they would be happy to help out with a project like yours and offer very reasonable prices. It is also beneficial for them, as they can get rid of a large quantity of their stock at one time (especially if you are happy with used elements). So it's a win-win for everyone involved.
> 17 votes

# Answer
The cheapest option would be to join your local RLUG and participate in the lugbulk program, however given the time constraint of having an exposition already next fall this might not be feasible (lugbulk takes nearly a year to organize, order, deliver, sort, etc...)

The next best solution would then be to visit your lego store again and ask the personnel for several bulk cases of bricks. These are the same cases they use to fill up the wall. They calculate the price so it roughly matches the price you would pay if you filled the cups very efficiently (you can roughly fit 130 2x4 bricks in a large cup). So not much discount but it saves you a lot of time.
> 3 votes

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Tags: bricklink, pick-a-brick, bricks-and-pieces, lugbulk
---


# Question
Title: Trying to find piece ID on instructions w/ no ID
I've gotten online instructions and the above piece is required, but annoyingly the piece ID is not in the instructions and I can't find it on any lego websites. I just want to know what the piece ID is.

# Answer
This is the ID 4211760 which in the LEGO movie sets holds the piece of resistance in place on Emmet's back. See for example instructions of set 70801 (Melting Room).

Bricklink lists it as "Minifig, Neck Bracket with Back Stud" (42446).
> 3 votes

# Answer
Also you can use app for Android (or iPhone) for finding necessary piece. https://play.google.com/store/apps/details?id=com.betab.partsguideforlegotechnic
> -1 votes

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Tags: piece-information
---


# Question
Title: The 75192 Millenium Falcon is available again!
Or not? This evening, around 10 pm (in Germany), I noticed that the set was available. It is 11 pm now, and it returned to the "temporarily not available" status. Can it be sold out within one hour??

In the initial selling phase in 2017, the set had been available for some weeks. The buying limit was 3. I think it was limited to VIP members, but I think everyone who bought something directly from LEGO is a VIP member.

Anyway, according to some rumors, the set would be available again in February. So I expected LEGO to produce as many Falcons as they can to flood the market after building up tension and demand. It seems, however, that 75192 will remain a rare set that will be sold out most of the time.

What I am really asking is this: Do you know or remember the situation regarding availabilty of similar sets in the past (e.g. the 10179 Falcon)? Does LEGO have a different selling strategy with the 75192?

# Answer
> 2 votes
> Can it be sold out within one hour?

Probably. If they sell all they have available, it would be "temporarily not available" again.

This set has been known to sell out the same day it becomes available in other countries.

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Tags: shopping, star-wars
---


# Question
Title: Is there any reason behind fancy bricks in invisible places?
In set 60080 there is a blue bick with pretty fancy shape. There are also hardly visible bricks in other places. Is there any reason? Why are these bricks used? Any official or semi-official explanation?

As far as I remember back when I was young, such pieces were rare, and (if included at all) were used in alternative models proposed on the back of the box. But this set has no such alternative models shown.

# Answer
This piece is only two plates high, to have another piece in here you would need to stack two plates, which would

1. make the total pieces count rise, or more expensive
2. might be more difficult to tear down by hand
3. probably less sturdy (with a piece on it acting as a lever stacked plates could pry apart)

Sets designers are under constraints for both piece count, piece prices, ease of setup/teardown and sturdyness so I guess this arrangement was decided.

Some examples of other sets with the same kind of piece for the same kind of purpose:

set 4435-1

set 60108-1

set 60148-1
> 10 votes

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Tags: building, sets, design, city
---


# Question
Title: Are there any Star Wars vehicles that have not yet been produced in a Lego kit?
This includes all six films and the Clone Wars spin-offs. Every vehicle I can think seems to have been produced as part of a kit at some point. Are there any that haven't?

# Answer
> 20 votes
As far as I know, all of the most common vehicles have been produced, but I could be forgetting something. There are many obscure vehicles which have not been produced, but I don't see any reason to try to list them all. Some examples would be many of the pod racers from Episode I, many of the hundreds of vehicles shown on Coruscant, or several of the speeders seen in the Mos Eisley approach in Episode IV.

The most notable vehicle that I can think of that has not been produced to my knowledge are the Royal Cruisers from the prequels:

Update:

I had previously been mentioned the Nebulon-B Frigate featured in Episode V and VI:

The Nebulon-B has now been produced:

# Answer
> 9 votes
There are quite a few:

* The Naboo silver cruisers \- I think there were three in all - none produced.
* Several speeders in *Episode II*, all seen in the city and several transporters too.
* The Jedi speeders, some have been made, but not in all the colours seen in the movies.

And as for the clone wars series, the list becomes lengthy...

# Answer
> 9 votes
The ones from the original 6 movies and that should have been made:

* Naboo queen silver cruiser from episode 1 (with queen handmaid fig(s)!)
* Clone quadrans (if I'm naming them correctly) from episode 2 (the guns taking down a Trade Federation ship)
* Rebel transport shuttle from episode 5 (escaping Hoth) and 6
* Rebel medical frigate from episode 5 and 6
* Mon calamari cruiser

Very optional in my opinion:

* Trade Federation admiral ship
* Trade Federation transport ship
* Separatist cruiser from the opening scene of episode 3
* The two other Naboo cruisers
* A Uta Pau shuttle seen on two or three images (and natives from the planet in the set please!)
* A clone tank seen on two images on a bridge under snow in the order 66 scene

Not ships, but still should have been made:

* Gungan city (and, why not, one big creature carrying their shield generator and one of their catapults)
* A Jedi Temple?
* Kaminoans!
* Geonosis arena beasts
* One of the Skywalkers house?
* Republic Senate with Sidious and Yoda fighting
* Bizarre blue/purple creature on which clones are riding on Felucia (order 66 scene)
* Mustafar locals (humanoids and lava beasts seen on one image)
* Asteroid field locals sheltering Padme at the end of episode 3
* Bantos... Bantas... Ban... you know the big hairy thing the Tuskens are riding in episode 4

# Answer
> 5 votes
Millions! Separatist War Ship,UT-AT, Republic Assault Ship, Umbara Military Canon, and many many ships from the Clone Wars TV show (From Arc's this season mostly)

# Answer
> 3 votes
Banthas! That to me is the largest oversight in Lego's portrayal of the original movie so far. This is made even more baffling with the upcoming release of a "Tatooine battle pack" that comes with yet another Tusken Raider...missed opportunity there!

# Answer
> 3 votes
TPM: Trade Federation Battleship, Trade Federation Landing Ship, Naboo Royal Starship, Coruscant Air-Taxi

ATOC: H-Type Nubian Yacht

TCW: Trident Drill Assault Craft, Umbaran Starfighter

ROTS: Separatist Cruiser, The Invisible Hand

REBELS: Imperial Interdictor, Mining Guild TIE-Fighter

RO: AT-ACT, TIE Reaper, The Profundity, Hammerhead Corvette, Zeta-Class Imperial Shuttle

ANH: pretty fleshed out

TESB: GR-75 Medium Transport, Nebulon-B Frigate

ROTJ: Mon Calamari Star Cruiser

TFA: pretty fleshed out

TLJ: First Order Dreadnought, Canto-Bight Police Speeder, The Raddus, The Supremacy

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Tags: star-wars
---


# Question
Title: Is there a way to strengthen individual pieces?
Is there a way to strengthen fragile parts? Say for example the lime green socket joints from 2007? Or the 2008-2010 socket joints? I would like to know if there is a possible way to do so?

I am interested in preventing the breakage of a piece, while still keeping the ability to pose the figure

# Answer
Those joints are based solely on friction, which comes from:

* the "bite" of the socket - how rigid the containing socket is
* the rigidity = non-elasticity of the ball
* the shape of the ball
* the relative friction between the two surfaces

The old plastic gets weaker with time, which rules out fixing the first two causes.

The shape of the ball would be pretty hard to fix; also the shape is not likely to have changed much.

This leaves the friction itself. So what you could do:

* spray an adhesive on the ball to make it tackier
* glue the joint in place (KRAGLE!!)
> 1 votes

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Tags: piece-information, bionicle
---


# Question
Title: What is the best solution to power up two 5292 buggy motors?
I have two buggy motors, 5292 like this:

I see powering each separately and using two IR receivers soon triggers the receivers' protections and the motors are stopped.

My aim is not speed, I see battery options powering with 7.2-7.5V instead of others powering with 9V, obviously the latter ones performs faster, but I try to have a safely working setup, without burning components.

What is the best way to power up them? Is there a way to avoid using Android apps and bluetooth, or EV3 stuff, by using an IR setup at all? Is it possible to avoid SBicks and BuWizz? If not, are these reliable? I see people talking about LiPo instability. Is it that fire-hazardous?

Having in mind that Lego has overheat protections that often stop the motors on load, first question would be: is there a setup with Lego's LiPo battery to avoid the known hiccups behavior, without bypassing the protections?

And I have a side question: how to control a buggy motor using its box 54734, that come together in the 8287 set, with an IR Receiver? Mine simply does not power up the IR. I've tried all Lego Power Functions extension cables, the IR receiver doesn't lit.

**Update**

I have a RC power unit now:

A thing that nobody tells ~ and I've searched a lot ~ is that steering goes 45°, unlike the servo motor that goes for 90°.

Building big means heavy (I try the agrof's class 1 buggy), so I've used multiplication twice in order to achieve the same 90° with the RC unit. This powered down the steering so it could not work when not running. A crackling sound is heard from it too, when tried. The multiplication is like this:

agrof's steering is pretty complicated to change in order to use a 20T instead of 12T due to the steering wishbones and link positioning, as the 20T is bigger in diameter. Also, don't know if it is enough.

Now, similar to Michael Verschaeve's idea, the 45° steering could be used to action a switch in order to steer using a servo motor, but seems pretty weird to me.

# Answer
The Lipo, thermal protections kicks in when consuming about 1A, while the buggy motor will consume 1.3 A when loaded but not stalled. So for two buggy motors, best would be 3 lipo's in parallel but perhaps you can get away with 2. The V1 receiver, only 850 mA before the protection kicks in, so not enough to power 1 buggy motor, let alone 2. The V2 receiver, 1.5 A before the protection kicks in, enough to power 1 buggy motor...

What might be a solution is having the V1 receiver control a medium motor or servo which mechanically switches a 8869 control switch which in turn switches the buggys on and off...

As for the old battery box, I think the reason you don't get it to power a V1 receiver is because power functions have two pairs of wires, a control pair and a pair that gives a constant voltage.

M,L and XL motors only use the control pairs of wires.

A servo uses the voltage pair to keep its position and the control pair to determine the position.

A receiver uses the input voltage pair to power itself, ignores the input control pair, forwards the voltage pair to the output voltage pairs and places control voltage on the output control pairs as it's instructed by the remote.

When using PF to 9V conversion cables, I think only the control pairs get connected, never the voltage pairs so the receivers cannot be powered by 9V battery boxes or cables...
> 4 votes

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Tags: power-functions, motor
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# Question
Title: Is 32013 a drop-in replacement for 3651?
In my old sets there are many 3651 parts that are broken.

As far as I remember, these sets do not use studs on the piece. Per this answer, new piece with the same function is 32013:

Can I just buy some of 32013 and use it everywhere instructions tell me to use 3651? Is it supposed to just fit? I could try to build 3651 but I'm afraid I'll break it again.

# Answer
Dimensions are, respectively:

Distance between one axle and end of another also did not change. So for most builds it should work.

Incompatibilities include:

* Obvious lack of studs
* Use as in Lego Technic Universal Set 8034 as a locking mechanism for lift system, as seen on the box:
* *This answer was posted as Community Wiki, please add incompatibilities if you know them*
> 8 votes

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Tags: technic, compatibility
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# Question
Title: What is a better algorithm for wall following with an ultrasonic sensor?
This wall following algorithm uses the ultrasonic sensor. It has a horrible worst case behavior. Place the robot about 3 cm too far from the wall. Instead of moving closer to the wall, the robot turns toward the wall and spins.

Place the robot too close to the wall and it works very well.

The sensor points out from the right side of the robot, in front of the powered wheels.

How should the algorithm be changed to handle the "too far away" case?

# Answer
If a significant distance from the wall, you'll need to turn 90 degrees in place clockwise, drive up to the wall and turn 90 degrees in place counterclockwise. I'd suggest mounting a touch sensor in front of the vehicle handle the part of driving up to the wall, if that is not possible, estimate from the scanned distance how far the vehicle should drive.

If close to the wall but not close enough to have the wall-following algorithm work correctly, I'd suggest "wiggling": Repeat the following steps until close enough to the wall:

* rotate left wheel forward by a small angle while blocking the right wheel.
* rotate right wheel forward by a small angle while blocking the left wheel.
* rotate left wheel backward by a small angle while blocking the right wheel.
* rotate right wheel backward by a small angle while blocking the left wheel.

In each step use the same angle (determine an optimal angle by trial and error)
> 1 votes

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Tags: ev3, programming, ev3-g, sensor-ultrasonic
---


# Question
Title: How to use this 5 and a half width windshield?
I recently went to Legoland in the Boston area and found the following windshield brick in the free build section.

Ignore my airplane build of questionable quality. What puzzled me was the width of the windshield piece I found in the part bin. As you can see it was roughly 5 and a half bricks wide. At the time I was confused at how the brick was intended to be used. Upon reflection my best guess is it might have fit if I would have used a 2x1 brick with the single center top bump on one side.

I couldn't make out the part number but I was able to barely discern it was a Lego branded part. The part number was in the center section of the windshield. I'd be interested to see a picture of the brick used in a custom build or an original set so I can see what others have done with it or how the designers intended it to be used.

# Answer
That part is a little tough to use on its own. It is generally paired with another element to create a 6-wide windscreen (6567c02):

Without the outer part, you don't have any nice stud connections to work with, and as you mentioned the size is strange, so it would be challenging to work it into a build.

I imagine it is now obvious how this is used, but since you asked to see this in a set, here is one example:
> 12 votes

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Tags: part-identification
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# Question
Title: Can anyone tell me what part or set this round Technic piece goes to?
I bought a large lot of LEGO and need help identifying this piece and or its set.

# Answer
That's not the best picture in the world, but it appears to be a Wheel 31mm D. x 15mm Technic, either dark red or reddish-brown. The dark red variation has appeared in a half-dozen Star Wars sets and two other sets, while the reddish-brown version has appeared in just one set.
> 6 votes

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Tags: part-identification, set-identification
---


# Question
Title: Can I still motorize Universal Building Set 8034 and other from that time with modern elements?
Set 8034 was supposed to be motorized using 8700. Of course, this is way outdated and kinda pointless to buy motor this old.

Current set for this purpose is 8293. Problem is, old motor was 5 studs long, new one is 6, and new set does not provide rubber band for power transmission. Can these be easily fixed? And is there anything else I should be aware of?

# Answer
> 7 votes
The length of the wire is another thing to be aware of. The wire attached to the motor in 8293 is only slightly more than 20 centimeters (might be a few centimeters more, I don't remember), you can double that by putting in the switch which has about the same length of wire, but it's still not much. I don't know how long the wire in 8700 was, but it looks longer.

You should also be aware that the new motor doesn't have a pin sticking out that rotates, but a pinhole, if you put in a 2L axle it will look about the same, but the notches on the newer (part 32062 - the older part 3704 didn't have notches) are in a different position (I believe they are in the middle of "each L", while the pictures show that the notch on the axle extending from the old motor is in the middle of the "half L" closest to the motor, the belt wheel was about ½L thick), so you'll have to think about how you place the belt wheel if you want to use a rubber band directly from the axle to transfer the motion. You can work around that with a (half)bush on the axle, but that significantly changes the circumference the rubber band goes around, as thus the gearing. (This section was significantly extended to address Michael Verschaeve comments, thanks goes to him for pointing out the issues I believe I have now addressed)

I don't know set 8034, but from the pictures it looks like it would be hard to fit the new motor due to the increased length.

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Tags: technic, compatibility, motor
---


# Question
Title: How to use the direct command to make EV3 motor backward?
I write the java language. I use ev3 direct command make ev3 motor to run,

example:

```
"opOUTPUT_POWER,LC0(0),LC0(0x01),LC0(20), opOUTPUT_START,LC0(0),LC0(0x01)"

```

In this case, the power is 20 so I write value (byte)0x14 resulted ev3 forward.

When I want to make the ev3 backward, how can I do??

I think change power 20 to -20, but I don't know -20 hex value.

# Answer
> 3 votes
The `LC0()` macro treats the value as a signed 6-bit integer.

From bytecodes.h...

```
#define PRIMPAR_CONST_SIGN 0x20
#define PRIMPAR_VALUE 0x3F

```

`PRIMPAR_VALUE` is where the 6 bits come from. `PRIMPAR_CONST_SIGN` means that the 6th bit is the sign. This means it has a range of -32 to 31, inclusive.

We must also keep in mind that computers use the 2's complement for negative integer values, so we can't just use `0x34` (`0x20 | 0x14`) and expect it to be -20.

`0x20` will be -32, which is the lowest number possible. So, to get -20, we would need -32 + 12 = -20. In 6-bit hex `0x20 + 0x0c = 0x2c`. But, you don't actually *have* to use hex formatted number. We can let the compiler figure it out like this: `(-20 & PRIMPAR_VALUE)`. This trims the number -20 down to 6 bits. In fact, this is what the `LC0()` macro does internally, so we can just write `LC0(-20)`.

If you need values larger than this range (e.g. -100 to 100), then you need to use the `LC1()` macro, which uses 8-bit signed integers. It has a range of -128 to 127. So, this will work too: `LC1(-20)`.

---
Tags: ev3, software
---


# Question
Title: High resolution flat view box cover images
Where can I find high-resolution, manufacturer quality LEGO box cover image files with flat view, i.e. without perspective view?

Is there a set database somewhere that collects them? I have tried searching but so far without success.

# Answer
> 9 votes
Lego does not release them for most sets so you might have to do what we at Brickset do when we want them and use software to correct the 'distortion'.

---
Tags: set-database
---


title: Sensor usage during manual control

text:
# Question
Title: Sensor usage during manual control
I created a design challenge where students will use their touch sensor and ev3 brick to play a game of freeze tag. Is it possible to have a program where they can manually control their robot via smart phone app, and when another robot presses another robots' touch sensor, they become disabled and play a noise warning they are turning off and done playing, being "Frozen".

# Answer
The EV3-G programming language has mailbox blocks where it can receive bluetooth messages. You could write a program that until the touch sensor is pressed keeps processing the messages to control the robot. The hard part here will be writing an app for the smartphone that sends the messages, however the BT protocol EV3 uses is documented and apps are already available implementing the messaging system, e.g. in C# here: https://github.com/jovabel/EV3Messenger There's also the lego commander app, but I think the instructions sent by it bypass any program running on the EV3 brick, or rather they run in parallel so I'm inclined to think that the only solution is to write your own smartphone app...
> 2 votes

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Tags: remote-control, sensor
---


# Question
Title: Please identify this black 2x2 tile with sticker, sunset with 2 palm trees and boat
Can someone identify the set origin of this sticker on a black 2x2 tile?

# Answer
> 8 votes
This is part # 3068bpb0183 : Tile 2 x 2 with Hovercraft Sunset Pattern (Sticker)

From 8485-1: Control Centre II

---
Tags: part-identification, set-identification
---


# Question
Title: When did Lego switch from 4 to 6 stud width of Windscreen?
All my old sets have cars with windscreen 4 studs wide. No matter if it is a jeep, truck or what - cars was 4 studs, usually 3823 or 2437. Now, in most modern sets, car windshield is usually 6 studs wide, like 92583.

I'm interested when this transition happened. If it's possible, I'll be also glad to hear why - was this change caused by introduction of other bricks? New "series" of a City theme? General overhaul?

# Answer
I noticed this, too. But only after the "Speed Champions" came out a few years ago. (I didn't give much attention to CITY.) It seems to me like the LEGO Racers got wider, more detailed sets starting from 2008 or so.

Also: I often check the Bricklink inventory part page (example: 92583), to find the **Years Released** under the "**Item Info**" section. I cross reference those dates with the list of sets that an item was used in.
> 2 votes

---
Tags: history, city
---


title: What part is this 2x2 curved slope?

text:
# Question
Title: What part is this 2x2 curved slope?
This is the piece I'm looking for:

I need the part number.

# Answer
That is 15068 PLATE W. BOW 2X2X2/3:
> 3 votes

---
Tags: piece-information
---


# Question
Title: Which Lego Set Is This, large white and tan walls, blue base plates?
I picked up a few loose sets. No instructions. Any help appreciated.

# Answer
That looks like the Taj Mahal (10189):

The instructions from Lego.com are easily found on Brickset under the instructions tab. It's a beautiful set if you have all of the pieces. Good luck!
> 8 votes

---
Tags: set-identification
---


title: Why do LEGO parts break?

text:
# Question
Title: Why do LEGO parts break?
I disassembled the Airplane set 7893 with normal pressure on the bricks and it happened that some parts broke like dry brittle leaves, see picture. The storage conditions have been in the open and some of the blue bricks show a bit of discoloration. I bought the set online and do not know what happened to it in last 10 years or so. The set is not that old, made 2006 or later and I wonder what can cause this weakness of the bricks?

# Answer
> 2 votes
In my experience, this happens when the lego has been washed with a too strong detergent or too high temperature...

---
Tags: repair, plastics
---


# Question
Title: When did LEGO stop using perforated plastic bags and switched to simple ones?
I'm talking about those sophisticated bags used to pack the contents of the sets in 90's. Here is an illustration of such bag:

Could anyone tell when LEGO started to pack the majority of their sets into simple bags instead of perforated ones?

# Answer
> 4 votes
AFAIK TLG still uses these bags, and they are not unique to the 90ies. They are used for accessory bags, such as the one in your picture, or other various accessories such as these that came in the 2013 Friends Advent Calendar:

https://store.bricklink.com/v2/catalog/catalogitem.page?S=41016-11

---
Tags: manufacturing, packaging
---


# Question
Title: Can you extract a program from the EV3 brick to the computer?
As part of an assignment, I made a program for my EV3, but however my computer automatically restarted, so I lost that program. I need to show the program! However, the program is still in my brick. So, I was wondering, is there any way to extract a program from a brick to my computer? And if there is, what would I need? (extra software, Bluetooth, connection cable)? Thanks

# Answer
**Update:**

There is a tool at http://ev3treevis.azurewebsites.net/ that can be use to create a new `.ev3` file from a `.rbf` file recovered from an EV3 brick. Some information will be lost, but at least simple programs should be able to be recovered.

**Original answer:**

You can extract the compiled program from the EV3. Compiled programs have a `.rbf` file extension. However, these files only contain EV3 VM bytecodes and cannot be converted back to the EV3-G project file format (`.ev3p` file extension).

Details about extracting the program from the brick and what you can do with it has already been answered here.
> 6 votes

---
Tags: ev3, programming
---


title: LEGO family identification

text:
# Question
Title: LEGO family identification
I found this little guy here, I remember I already had it in my childhood (~30 years ago).

Could somebody tell me what LEGO family it is?

The grid size is 2x2 LEGO studs, it just fits right onto one Duplo stud. On the inside I see the LEGO logo and the following indication "4 01".

# Answer
> 4 votes
Seems to be 4224c01: Basic Figure Finger Puppet Female (bfp001)

It appeared in two sets: 1050-1 Basic Pack (1986) and 1089-1 Lego Basic Figures (1985)

Edit (thanks to @Mark comment):
While Brickset list only 2 sets with this figurine, BrickLink lists 25.

---
Tags: part-identification, minifigure-identification
---


# Question
Title: Is it possible to retrive a text file from an NXT?
I am on a SeaPerch building team which is starting to use a Vernier Dissolved Oxygen probe, connected to an NXT to log the data. I have a bit of programming experience, but nothing in particular with NXTs (or GUI programming for that matter) and managed to get a very simple program written which logs data collected from the probe to a text file stored on the NXT (there will be no computer available in the field, so everything has to be stored on the NXT).

My problem is, I can't seem to figure out how to get the file from the NXT's memory and copied to a computer. It doesn't seem to be able to be accessed from Windows Explorer as a drive. Is it possible to get files off of it like a flash drive, or would I need to do something else to get the data?

# Answer
> 8 votes
Using Mindstorms NXT software (NXT-G), you can transfer any file from NXT to computer. Open "NXT window" (NXT icon in the lower right corner of interface), then go to "memory" tab. Select a file in NXT and click on "upload" button.

Or - more convenient - you may use "NXT Explorer" feature of BricxCC (in the "tools" menu).

# Answer
> 0 votes
This is not an answer, just an answer to the @laurentien comment posted in the existing answer.

---

The "NXT window" icon is the orange L-shaped button (see red arrow).

The "memory" tab is the other red arrow.

---
Tags: nxt, mindstorms, 3rd-party
---


# Question
Title: Can you help me identify the set this dark grey pedestal sub-assembly belongs to?
Can anyone help me identify the set this sub-assembly belongs to?

# Answer
This is from 70114-1: Sky Joust
> 10 votes

---
Tags: set-identification
---


# Question
Title: Will my mighty white rocket yellow in direct sunlight?
I recently bought the Saturn V and placed it on my windowsill where the rocket is exposed to the direct impact of sunbeams every day. Having encountered several yellowing effects on older white parts I wonder if this will speed up this unwanted process of discoloring?

# Answer
Absolutely it will. The yellowing is caused by exposure to UV light, which it will get more of with direct sunlight shining on it. If it has to be in the window you could look at some glass coverings that block some of the UV, or find a home for it else where under electric light.
> 12 votes

---
Tags: colour, preservation
---


# Question
Title: Two separate functions of 5282 RC remote?
Given the RC set of 5282 and 6272c01 below:

Is there a solution to use the two paddles that command the auxiliary output of the receiver for different functions?

For reference, see this at 1:45.

I'm trying to light two different 8870 led lights, one with the left paddle, the other with the right paddle.

# Answer
> 3 votes
With only using existing non-modified LEGO parts a mechanical solution with a servo motor, two polarization switches and cluch gears is thinkable, but this is all really cumbersome...

It's a bit ironic really, there's a bit of (trivial) circuitry in the 2x2 black brick before the wires of the LED lights split that causes the LEDs to work no-matter the polarization, because LEDs by their nature only work when the correct polarization is applied...

One solution would be to modify the circuitry in the 2x2 plate.

Schematics are here: http://www.philohome.com/pf/pflights.htm

What basically needs to happen is that the diode bridge is removed and the C1 wire is soldered through to the + side of the leds (to the resistors) and the C2 wire to - side ...

Same for the other pair of leds but switching C1 and C2...

---
Tags: technic, remote-control, lighting
---


# Question
Title: What material is used to make capes and cloth in LEGO sets and where do I get it?
It seems like a conspiracy to keep everyone from knowing this.

Custom cape sellers don´t say what it is, the women from the draperies I questioned always say something along the line of "coated propylene" which is no longer in the making because the only company who sold it went bankrupt in 2003.

Even LEGOs customer service can only say "Acrylic matte medium" which apparently is some kind of paint artists use to paint on canvas.

# Answer
> 8 votes
The term *acrylic* is used for many mediums, like acrylic paint (liquid), acrylic fiber (clothing), acrylic rubber (flexible) and acrylic glass (really hard).

So, as you see, it is possible to make those capes out of a type of acrylic material.

# Answer
> 7 votes
It is fabric - probably cotton or polyester - coated with an acrylic substance that makes it more durable and tear-resistant. You can easily print on acrylic-coated fabric using standard laser printers.

You can purchase acrylic-coated fabric through suppliers that sell sign-making supplies as well as art supply shops.

# Answer
> 2 votes
see this tutorial on Creating custom fabric elements for Lego minifigures http://www.minifigcustomizationnetwork.com/howto/899

# Answer
> 2 votes
I've used iron-on patch material (the thinner twill variety that comes in bright colors) with success for my kids' minifigs. I cut it out with fabric scissors and use a good hole punch for the holes. Takes about one to three minutes a cape depending on complexity and is $2.47 at Walmart for a 4 pk of 5"x5" patches.

# Answer
> 0 votes
Paint everyday fabric with black acrylic paint. Use a paint brand like AppleBarrel. This will not give you fabric exactly like LEGO, but it is durable, cutable, and can be hole punched. You can paint over it with any color once the initial paint has dried.

NOTE: This was not my idea. It came from a YouTube video by NobleArtist. Check out his channel.

---
Tags: manufacturing, accessories
---


title: Problem with "warping" of LEGO water

text:
# Question
Title: Problem with "warping" of LEGO water
I was trying to imitate the cool water technique of Legopard on MOCpages.

Sadly, I found that when I did it on a large scale (about 46x46 pegs), the water tends to warp upward in the transverse direction, curling the edges. I cannot get my lake to sit flat. I get the standing wave in the longitudinal direction, as shown in the picture, but the entire sheet warps in the transverse direction.

I first thought that perhaps mold type played a role, but building it in either clip type gave the same results.

Next, I tried putting in longer 1x plates below to hold the longitudinal wave as shown in the picture, while hopefully straightening the transverse curl, but the problem is that the 1x1 clips hold the water/tiles too tight in the transverse direction, thus pulling the pieces too close together, so the plates end up making the warp worse as they push the bases apart further (due to the normal tolerance or piece spacing).

I would love any ideas people can offer. I am not sure how Legopard got his to sit so flat. I am finding that even 6 tiles wide gets a noticeable warp and his picture is many times that.

# Answer
> 4 votes
This image of the same model shows that the whole set sits on a frame of bricks. In the inside, you could place bricks underneath wherever necessary to attach the water plates (not only 1x... but maybe 2x10, or several 2x4 in a row). They are invisible, so color and type don't matter. If this row of bricks reaches from one side of the frame to the other, it can shift to allow the longitudinal waves but it cannot curl up transversal(ly?).

# Answer
> 4 votes
I admittedly don't have the 46x46 = 2116(!) 1x1 clips to properly build this, but I was able to build a small sample to replicate the problem.

Because this construction technique eliminates the natural tiny gap between elements, you can't easily reinforce it just by attaching plates and bricks to the underside. This construction is essentially "out of system". When you attach bricks underneath, you are forcing an error between this and standard system construction. This is why you see the "strong v" when bracing this with plates or bricks underneath.

One way that you might be able to brace it is by using a continuous offset of some sort. Here's an example:

You could also try building it without any reinforcement and then try to flatten it out (e.g. you could leave it under a pile of books overnight). I'm honestly not sure if this is likely to work, and it may permanently deform your bricks if it does, so I can't strongly recommend it. Realistically, this technique is already putting these parts under a lot of stress and may permanently harm them anyway.

# Answer
> 0 votes
To help share ideas, in case somebody else runs into this someday, I will post another idea I have been playing with. I don't know which solution I will go with yet, but I add this idea to help others.

The idea is basically to create some fault lines through the lake where I can hinge the water and avoid the accummulation of stress. I have started playing with it on one end.

Basically, I remove all of the 1x1 clips across the entire width of the lake, but using some pattern that allows a somewhat natural look to remain.

Next, I put a collection of 1x plates beneath that area, so that the colors don't look too bad.

Finally, at my high points in the wave, I use some 1x hinge plates to connect the two pieces. Thus we keep a single top surface, but cause the accummulative warp to remain minimal.

I will try to get a picture of the underside and top to help people see what I am doing.

---
Tags: building, water
---


# Question
Title: How to protect my LEGO city from the dust?
I have a LEGO city with all the modular LEGO in my bedroom. But the dust is killing me at nights. How can I protect them? Where can I get those display domes?

# Answer
> 6 votes
Where I'm from it's called Plexiglas. Other tradenames are Crylux, Acrylite, Lucite or Perspex... Anyway, you can get sheets of it cut to size in D.I.Y-shops or hardware stores to build your own domes. If you are less handy, you can find lots of shops offering standard or custom solutions. If I google "plexiglas", I find dozens of solutions near where I live. I know of one person who had a custom pyramid shaped Plexiglas dome made for the 10181 set (Eiffel tower)

# Answer
> 2 votes
I know it is a bit simplistic, but you might try just using a light sheet. If it is a light, tight fabric, it probably will go on and off pretty easily.

If you have lots of delicate parts on your buildings, you could get some small stilts of some sort to hold the sheet up over those areas. That will give you the circus tent look, I imagine.

---
Tags: cleaning
---


# Question
Title: Is there a list of the most common Lego Technic parts?
I searched the internet for this and I found a list of complete sets. But I am looking for a list of the most common (and in some sense the most important or most helpful) individual Lego Technic parts. Is this available somewhere?

# Answer
> 5 votes
On Brickset, you can browse parts in the technic subcategory and you can sort by "Set count", i.e. the number of sets the element appears in.

https://brickset.com/parts/category-Technic

So that would take care of your "most common" requirement. I'm afraid that "most important" or "helpful" is rather subjective and hence difficult to quantify and have lists sorted by those measures...

---
Tags: technic
---


# Question
Title: Can you identify this piece of non-LEGO submarine from a sketch?
This is from a submarine set I bought on aliexpress. It's not LEGO but usually the pieces are the same. I'm missing this piece and cannot identify it. Can you guys help me?

# Answer
If you are looking for the LEGO equivalent of it, it's a Slope, Curved 2 x 2 No Studs, 3 Side Ports Recessed: https://www.bricklink.com/v2/catalog/catalogitem.page?P=44675#T=P
> 5 votes

---
Tags: piece-information, part-identification, clone-brands, 3rd-party
---


# Question
Title: Which set does this bag belong to? Blue and clear orange pieces
Hi can you please help identify which product this belongs to? Bought this from second hand shop.

The spiked flail is part of a smaller bag - no number however it was in a larger bag with a large number 2 on it, below which are the numbers 304R7:

Hope this helps in identifying it.

# Answer
> 7 votes
Based on the title of the post and Larme’s clarifying comment, you are looking at 59232 Minifig, Weapon Spiked Flail/Mace in a bag with date code 304R7 (which indicates this bag was produced in 2017).

Looking at BrickLink, there are several sets made in 2017 that have this element in Flat Silver (no other color was produced recently). There is one set from 2016 but that set did not come with bags AFAIK. Most are from the Nexo Knights range, but one is from the Super Hero Girls line. If the bag has no large number on it, it must have come from a small set, for example 70361 Macy’s Dropbot Dragon. If the bag does have a large number on it (1, 2, 3 etc) it will be from a larger set. Without more information on what is in the bag besides the Flail, it is impossible to narrow the set down further.

UPDATE: Now that a bag picture has been provided, it is clear this bag belongs to set 70351 Clay’s Falcon Fighter Blaster from the Nexo Knights theme. The Technic connector with hole in the middle in Orange is only in this set (out of all the sets on the list containing the Flail).

---
Tags: set-identification
---


# Question
Title: Power Function Converter Cable for LEGO MINDSTORMS
This is a follow up to this question: How to use Power Functions with Mindstorms EV3?

The question was asked in 2013 (5 years ago). Fast forward to 2018, the product that was suggested in the answer is retired: https://shop.lego.com/en-US/Converter-Cables-for-LEGO-MINDSTORMS-NXT-8528

Is there a replacement for the retired product?

Is there any better option, other than what is shown in this video?

https://www.youtube.com/watch?v=Ns3TODgRlCE

# Answer
No, there is no replacement yet except soldering your own cable or using third party products. Basically the answers in that question of 5 years ago are all still valid. Mind that LEGO is transitioning to a new power functions system (with motors and sensors as in the boost and WeDo 2.0 products), perhaps we'll see solutions for that quite soon.
> 2 votes

---
Tags: mindstorms, power-functions
---


# Question
Title: Quality of Brick, Modified 1 x 1 with Headlight over time
I have a problem with my 4070 Brick, Modified 1 x 1 with Headlight .

I packed my Lego and put in the basement at the end of previous century. Now I see my "headlight" bricks are broken at the bottom, or, if not visibly broken, they lost gripping strength. It applies to white, red, gray and blue. Actually, it applies to every color I have.

Are ones currently made more sturdy? Do they survive better? Or is replacing them only a temporary solution?

# Answer
I just got a call from LEGO Support. I can't repeat it word for word, but (translating to English) it was like:

> Over the last decade manufacturing process of this brick has undergone many improvements that have improved its durability. You shouldn't encounter any problems with new ones if you will buy them, and if you will have problems in two years after buy, we will replace them free of charge. Sadly, we can't replace parts older than 2 years for you for free.

Two years of play is quite a long time, so it seems they are pretty confident about quality now.
> 5 votes

---
Tags: piece-information, quality
---


# Question
Title: Is there a drop-in replacement for 4275 + 4276 hinge?
Both parts are not in production since 2008.

Hinges in my sets are in various conditions, some of them are way too loose to my liking. No ones fault, I was active kid who built a lot. But now it's like 10 years too late to replace them with new ones. Or is it? I'd prefer original Lego brand replacement that can be used without changing anything else in building instructions, but other ways to replace them are welcome, too. Restoring the ones I have is another question (that probably was already asked).

# Answer
Not exactly drop in replacements, this particular modified plate has no protrusions around the hinge, it's entirely flat.

I see two possible replacements:

44301 and 44302. However they "click" in angles of 22.5 degrees and have protrusions...

60478 in combination with 63868 (clip and bar connection) is freely rotating but ofcourse again protrusions...
> 2 votes

---
Tags: piece-information, compatibility, replacement-parts
---


# Question
Title: How to use the ultrasonic sensor on mindstorm NXT
I've been struggling for some time on this. I'm trying to code the robot to move when the distance is above a certain integer and stop when the distance becomes lower than the certain integer. I'm coding in Eclipse Helios. My code is below:

```
import lejos.nxt.Button;
import lejos.nxt.Motor;
import lejos.nxt.SensorPort;
import lejos.nxt.UltrasonicSensor;

public class robot {
    public static void main(String[] args) {
        UltrasonicSensor us1 = new UltrasonicSensor(SensorPort.S4);

        System.out.print(us1.getDistance());

        if (us1.getDistance() >= 25);
            Motor.A.setSpeed(50);
            Motor.C.setSpeed(50);
            Motor.A.forward();
            Motor.C.forward();

        if (us1.getDistance() < 25);
            Motor.A.backward();
            Motor.C.backward();
            Button.waitForAnyPress();
    }
}

```

# Answer
It's a little unclear from your question where this is currently failing, but I do see a couple issues with your code.

1. Your `if` blocks are probably not doing what you expect. You should include braces to conditionally run the block following an `if` statement. As written, all of your code executes all of the time. This is a tricky bug to spot, as it looks correct, but isn't. You probably want to change this:

```
if (us1.getDistance() >= 25);
    Motor.A.setSpeed(50);
    Motor.C.setSpeed(50);
    Motor.A.forward();
    Motor.C.forward();

```

To this:

```
if (us1.getDistance() >= 25) {
    Motor.A.setSpeed(50);
    Motor.C.setSpeed(50);
    Motor.A.forward();
    Motor.C.forward();
}

```

2. You say that you want the motors to stop, but it looks like you are actually reversing them. You'll likely want to change this:

```
Motor.A.backward();
Motor.C.backward();

```

To this:

```
Motor.A.stop();
Motor.C.stop();

```

Your code may still need some tweaking, but hopefully those two fixes get you back on track.
> 4 votes

# Answer
Second `if` needs to be replaced by a loop... Very unlikely that the distance will be immediately less then 25 cm after starting the motors, you need to continuously check... And stopping the motors can then be done unconditionally (i.e. outside the while loop) Something like

```
while (us1.getDistance() >= 25 && !Button.ESCAPE.IsDown())
{
   Thread.sleep (1000);
}
Motor.A.stop();
Motor.C.stop();

```
> 1 votes

---
Tags: mindstorms, nxt, sensor-ultrasonic
---


# Question
Title: What about Power Functions motor, S size?
LEGO Power Functions has motors in ,  and XL sizes. Usually, if someone uses this size designations, the smallest one is S. It would make sense to have them named S, M and L if there were meant to be only 3.

Now, for my personal "rebuild, restore" project, I'd need something a bit smaller than , to go with my old sets. Is there any S size power function motor? Was there? Was planned, but cancelled? Any official or semi-official info on it?

# Answer
Only in 2012 the L-motor was released. The M and XL motors where released in 2007. That is a gap of 5 years where people were even more confused about the size options...

Anyway, no smaller motor with power functions

However if you are willing to go with the 9V system (possibly with conversion cables), there's the mini and micro motor, standard motor is also a bit smaller in length.

More info here: http://www.philohome.com/motors/motorcomp.htm
> 4 votes

# Answer
As far as we know, no other motor sizes were planned. It's possible they were named this way to allow for future expansions, like when the L motor was added.

It's worth noting that it's unlikely we will see any new motors come out for the current Power Function system, as Power Functions 2.0 was just recently announced at the Nuremberg Toy Fair and features the Boost connectors.
> 4 votes

---
Tags: technic, power-functions, motor
---


# Question
Title: Using the unregulated motor block and conversion cable to light LEDs
I have the following setup:  It consists out of

This is my program:

It works fine if I provide a negative power to the unregulated motor (i.e. the LEDs light up for 5 seconds), however with a positive power, it flashes just shortly. This does not seem to depend on the orientation of the connectors between the conversion cables.

Also the motor test pane on the EV3 brick behaves similarly, the LEDs flash when pressing the button to move 'forward' and lights up continuously when pressing the 'reverse' button.

So I have an acceptable workaround, but I would like to know why this is.

# Answer
> 4 votes
The light turning off happens because of the Device Connection Manager in the EV3 firmware. The algorithm used to detect when a motor is connected relies on there being a load on pins 5 and 6 of the output ports to determine if the motor is a Large or Medium motor. The 8528 adapter cable only has wires on pins 1 and 2.

When you use a VM command (via a programming block or by using the on-brick app) to tell a motor to run, it forces the motor to run, but then the device connection manager immediately resets everything because it doesn't think that a motor is connected.

Also see How to use Power Functions with Mindstorms EV3?

~~The fact that setting a power of -100 keeps the power on continuously, though, is new to me. I'm at a bit of a loss to explain that observation.~~

UPDATE:

I've done some digging and now I better understand what is going on.

Output port pin 2 is connected to pin 6 via a 100k resistor as seen in the schematic diagrams below.

When the EV3 is instructed to run a motor in the forward direction pin 1 will have battery voltage and pin 2 will be at 0V. When running in reverse, however, pin 1 will be at 0V and pin 2 will be at battery voltage.

When using the converter cable, nothing is connected to pin 6 externally, so it will also be at battery voltage (pulled down slightly by R216 to +5V). This triggers an event in the device connection manager. Most of the time (but not 100% of the time) the EV3 will think that it has a motor attached because of this and so the LED will stay on.

---
Tags: ev3, power-functions
---


# Question
Title: LEGO Mindstorms 9797 (NXT Education base set) Software Download
Where I can download the Software for the LEGO Mindstorms 9797 (NXT Education base set)

# Answer
> 8 votes
I contacted Lego and they gave me this link for a PC:

https://fileshare.corp.lego.com/node\_share\_links/119233?token=7a9527d5-cd94-491c-88b3-689587eae5ae I don't have the link for a Mac, but you can ask Lego for it.

# Answer
> 5 votes
As of 2021, the retail version of the NXT software is still available for download from the official LEGO MINDSTORMS download page (near the bottom of the page).

The Education version of the software is available on the retired products download page.

# Answer
> 2 votes
The software is now available for download (Win/Mac) on LEGO Education site.

---
Tags: mindstorms, nxt
---


title: Can someone identify this brick?

text:
# Question
Title: Can someone identify this brick?
I'm looking for a kind of brick, the brand or the model, which has this specifications: The top has studs. The bottom doesn't have tubes. However, the bottom has support walls in the middle. Here is the picture:

What is the brand for this brickset (definitely not LEGO)? Is there a term for this kind of interlocking system?

# Answer
> 1 votes
I would say it it cold come from a brand from China, I can’t identify this system, but it is the opposite of that of a normal LEGO brick. It is still a normal 2x4 plate.

---
Tags: piece-information, clone-brands
---


# Question
Title: How can I repair a red 12v train motor from Set# 7730?
I have a LEGO 7865 Red 12 volt train motor from a LEGO 7730 train set. The motor has stopped working as it has been dropped on one of the wheels.

How can I open the motor case to effect a repair?

# Answer
> 1 votes
According to Bricklink, Set # 7730 has this motor :

bb12va Electric, Train Motor 12V Modern Type I with 2 round contact holes

For disassembly and repair you can look at this large post with pictures on Eurobricks by Andromeda

# Answer
> 0 votes
Unfortunately, repairing it will not work, if the shaft is bent, as the wheel would just fall off again.

---
Tags: trains, repair, 12v
---


# Question
Title: What is this long spiked black piece with rubbery orange tip piece used for?
Missing instructions but it should stand out if you’ve ever seen it

# Answer
This is part 61406pb04 Plate, Modified 1x2 with Angular Extension and Flexible Orange Tip, which comes in 2 sets:

8076 Deep Sea Striker

70135 Cragger’s Fire Striker
> 8 votes

# Answer
It sounds like you're going through a large collection, so may have this question again.

In general, if you have a LEGO part you don't recognize, the best thing to do is to search for the four or five digit design number on the underside. (It's small on many parts, molded into the plastic in the recesses.) In this case, the design number is 61406. There are several websites you can use to find it based on the design number; Brick Owl is one I'm fond of.

From there, you can look at the sets that used (and others with the same design but different colors) to get a sense of its usual use.
> 2 votes

---
Tags: piece-information, part-identification
---


# Question
Title: How to safely straighten 2569 Lego Antenna Whip 8H?
I have one of those, in trans-neon green, that's slightly bent. I don't want to break it or make it opaque. Is there a way to make it straight again without risk? Preferably universal way, but way specific to 2569 piece would suffice.

# Answer
It's not a particular rare part, easily replaced with bricklink for a couple of cents, so I wouldn't worry about damaging it. If it's bent it's damaged anyway.

For standard lego made out of ABS the procedure is to submerge it in hot water (hot to the touch but not scalding or boiling) for about a minute and then straighten it with your fingers or pliers in cold water...

However, this is a transparent piece so made out of PC instead of ABS. The melting point of PC is is about 50 degrees Celsius higher. So I guess the hot water will need to be near boiling...
> 3 votes

---
Tags: repair
---


# Question
Title: LEGO servo (88004) controlled by Raspberry Pi using python pigpio
I'm trying to control a LEGO servo (88004) using a Raspberry pi. I would like to use pigpio to get a more precise control (no shaking, like with gpio PWM).

It's work with a regular servo (3 wires). It kinda works with the 88004, it buzz when I test it (both with c1 and c2), but I can't make it move :-( (see code below).

Anyone have a suggestions to this problem?

"Kinda" working python code.

```
import time
import pigpio

pi = pigpio.pi()

if not pi.connected:
   exit()

#sudo pigpiod -s8
c1 = 23
c2 = 24
pi.set_PWM_frequency(c1,1250)
pi.set_PWM_frequency(c2,1250)
print(pi.get_PWM_frequency(c1))

#use NAME (GPIO02 = 2)

while True:
   pi.set_servo_pulsewidth(c1, 0)
   pi.set_servo_pulsewidth(c2, 0)
   print "reset"

   try:

      pi.set_servo_pulsewidth(c1,2000)
      pi.set_servo_pulsewidth(c2,2500)
      print "c1"
      time.sleep(3)
      pi.set_servo_pulsewidth(c1,0)
      pi.set_servo_pulsewidth(c2,2500)
      print "c2"
      time.sleep(3)

   except KeyboardInterrupt:
      break

print("\nTidying up")

pi.set_servo_pulsewidth(c1, 0)
pi.set_servo_pulsewidth(c2, 0)

pi.stop()

```

# Answer
> 1 votes
I figured it out :-) Using pi.set\_PWM\_dutycycle(c1, 128) # PWM 1/2 on makes it move.

In hindsight kinda obvious :)

---
Tags: python
---


# Question
Title: How many 2x4 Lego bricks would it take to build a real skyscraper?
As an exercise designed to communicate the scale of plastic waste in the oceans, which was estimated at 268,940 tons in 2014, I'm trying to describe how many life-size buildings one could construct with your basic 2x4 lego pieces of the same weight. A believe a 2x4 piece is 31.8mm long, 15.8mm wide, and 9.6 mm tall, not including the studs, and 2.32g.

Naturally, I don't aspire to simulate skyscrapers that anyone could actually live in, but I'm trying to come up with a defensible estimate for the number of bricks in, say, a Lego Empire State Building (1,250' tall, not including the spire).

One idea is to imagine building a solid structure that is completely enclosed. Another is to make a hollow one with double-layered floors and a solid base.

Forgive me for the open-ended question, but is anyone familiar with the mechanics of how one builds a extremely large structure with Lego pieces that, while not necessarily structuring sound for human consumption, and least holds together?

# Answer
> 7 votes
Great question. Others may have better answers for a more "realistic" design, but the math for a solid structure is actually pretty quick. Take the Empire State Building for example:

```
Height: 381m
Base: 129m x 57m
Volume: 381m × 129m × 57m = 2 801 493m³

```

And a basic 2x4 brick:

```
Volume: 31.8mm × 15.8mm × 9.6mm = 4.823424e-6 m³

```

The number of bricks needed to simply fill the volume is total volume over brick volume, so:

```
Number of bricks: 2 801 493 / 4.823424e-6 = 580 810 022 092 bricks
Weight: 580 810 022 092 bricks * 2.32g = 1 347 479 metric tons

```

Basically, you're looking at 580 billion bricks weighing in at **~1.3 million metric tons** for a solid structure the size of the Empire State Building.

This puts you at about a fifth of an Empire State Building's worth of bricks dumped in the ocean in 2014.

---
Tags: building, scale
---


# Question
Title: How can I program a motor to rotate towards the source of sound?
I have 3 sound sensors and a motor connected to four ports of the same brick.

My motor should rotate by some angle towards the highest sound detected by the sensor, and now I'm wondering how I'm supposed to do the following: write an infinite loop for continuous detection but once true the motor keeps on rotating for the same angle.

Is there some way to rotate for a certain angle, stop and then wait for the next sensor to detect the highest sound and then move again for the same angle and wait again?

I am using EV3 brick with NXT sound sensors and a large motor, so far my logic for detecting the highest sound detected by the sensor is working but I am facing problems controlling the motor.

# Answer
> 2 votes
To detect the highest sound you can use this code. It would help if you posted a picture of your bot, but with a general idea here you go:

```
FOREVER loop
{

if RightSensor > Left Sensor :
    if RightSensor > MidSensor :
        highest = RightSensor
    else :
        highest = MidSensor
else:
    highest = LeftSensor

if LeftSensor is the highest:
        turn left
if RightSensor is the highest:
        turn right
if MidSensor is the highest:
        do not turn
}

```

# Answer
> 1 votes
I don't understand the question. I do understand the quandary of trying to write code in the blocks available in the EV3 IDE.

I suspect the questioner really wants something like, given 3 sound sensors, how can I build and program a motor to point to the loudest sound. One could imagine a turntable with the brick on the platter and 3 sensors mounted 45 degrees from each other. Rotate until the middle sensor is loudest.

A part of the solution would be to determine which is loudest. See Vikhyat's psuedocode. This is a snippet to do that.

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Tags: ev3, mindstorms, nxt, programming
---


# Question
Title: What LEGO set are these decorated tiles from?
I have a box of LEGO from when my husband was younger and I have been going through and putting them in their sets for my son. I have now run out of the instruction books and still have some sets left.

Can anyone identify what set these pieces pictures may have come from? It seems like his sets are all from the 90’s.

# Answer
These came from a number of sets, including a handy "Decorated Elements" set that covered most of the printed parts from the mid-90s space theme.

However, Recon Robot appears to be the only one that contains two of the 2x2 tiles and only one of the 2x1 tiles.

Instructions can be found in a number of places, including on Let's Build It Again.
> 25 votes

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Tags: part-identification, set-identification
---


title: Steer with the LEGO Mindstorms EV3

text:
# Question
Title: Steer with the LEGO Mindstorms EV3
In my workshops I get asked regularly, what the turn option of the default steering block means (see the image).

Obviously, if the turn option is set to 0, the robot is moving forward. A positive value is turning right, a negative is turning left. So far, so good.

I looked in the source code and found a programming scheme I tried to visualize. A large comment within the code describes the process as follows:

> * Speed \[-100 .. +100\] is move forward or move backwards Turn ratio \[-200 .. +200\] is how tight you turn and to what direction you turn
>     + 0 value is moving straight forward
>     + Negative values turns to the left
>     + Positive values turns to the right
>     + Value -100 stops the left motor
>     + Value +100 stops the right motor
>     + Values less than -100 makes the left motor run the opposite direction of the right motor (Spin)
>     + Values greater than +100 makes the right motor run the opposite direction of the left motor (Spin)

So the turn ration is multiplied by 2, because as a user we can just put -100 \<-\> 100 in there. I then used this code to calculate some values:

```
for (var i = -100; i == 100; i++) {
  turn = i * 2;
  if (turn >= 0) {
    motorB = speed;
    motorD = speed - turn;
  } else {
    motorB = turn + speed;
    motorD = speed;
  }
}

```

If I visualize those values, I get the following image for speed 100:

That's fine. You can see the real turn value (the ones we as a user can set) and the calculated speeds for two (virtual) motors B and D. I tried this with the educator model and it works perfectly well.

But when I use the same code for another speed value (33), I get motor outputs that are too high in my opinion:

The Motors will have values over +100/-100. Is there a threshold in the code and the motor outputs will be cropped?

Did someone else dig into this? Did I made a mistake?

P.S.: I love such things. If someone is interested in doing more if this, just ping me. :)

# Answer
I can't say that I understand your problem, but maybe this link will help EV3 Move Steering Block Explained

If you are asking about how the steering parameters relate to how much the machine will turn, then that is going to depend very much on the geometry of the machine: wheel diameter and wheel separation.
> 4 votes

# Answer
I believe that it is the intention that the ratio between the speeds of the two motors is entirely determined by the turn parameter, not the speed parameter.

I think the following code better represents how the turn block behaves:

```
for (var i = -100; i == 100; i++) {
  turnfactor = 2*i/100;
  if (turnfactor >= 0) {
    motorB = speed;
    motorD = speed * (1-turnfactor);
  } else {
    motorB = speed*(1+turnfactor);
    motorD = speed;
  }
}

```
> 2 votes

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Tags: ev3, ev3-g, steering
---