# Question
Title: Can I repair a broken LEGO brick with glue?
I have a dump truck hinge piece that snapped in half when it got bent backwards too hard. Is there a type of glue that would be appropriate to repair the piece? Would superglue be a good choice? Obviously, it's never going to look new again, I'm more just concerned about the piece being functional if we wish to build more dump-trucks. Or is it a lost cause and after I go to all the trouble to glue it, it's just not going to hold?

Here's a picture of the broken part. Ldraw seems to list this hinge as parts 3324e + 314e

# Answer
> 14 votes
LEGO is very good about replacing broken parts - for free even. Visit the web-site and look on the bottom of the page under Customer Service for a "broken or missing parts" link (I can't check at current locale).

This is worth trying even if the set is old or you didn't acquire it brand new. LEGO doesn't usually care where you got the set; but if it's not recent there's a risk that the part is not produced anymore, and then they won't be able to replace it. But try anyway, they're usually very friendly.

You can also try calling Customer Service directly.

# Answer
> 6 votes
LEGO bricks are made from ABS. Therefore the most effective adhesive would be ABS cement from the hardware store that sells it for plumbing repairs. ABS cement in theory would *chemically*c weld the bricks back together.

# Answer
> 5 votes
It's sometimes possible to build a jig out of other Lego blocks to hold the broken pieces firmly together to allow the glue to set and the result to be very good. I use my worst-condition bricks for jig building because they almost always get glue on them or some kind of damage.

The location of the break on your hinge makes it a difficult fix, but you could try to make a basic jig by:

* Putting a couple layers of plastic wrap around the 2x8 portion (to keep glue off)
* Using a thin 2x4 plate at the end of the 2x8 bit of the hinge
* Using a 2x6 plate atop the previous plate to secure the 2x4 broken bit of the hinge in place

Then carefully align the broken hinge bits and apply a glue which will weld the break together.

# Answer
> 2 votes
I've had success repairing cleanly-broken parts (snapped without bending) using plastic cement -- the sort that contains methylethylketone.

1. Make sure the broken surface is free of dirt and other contaminants.
2. Brush a small amount of plastic cement onto both fracture surfaces. Make sure not to accidentally get any anywhere else -- this stuff works by briefly dissolving a thin layer of plastic at the join, and can cause damage if not used carefully.
3. Hold the two parts together for about 30 seconds to let the cement set.
4. Leave the repaired brick alone for a while (I usually let it sit overnight) to let the join fully harden.

That said, your hinge is a tricky repair. That's the weakest part of the brick, and it's quite possible the join won't be strong enough. It's also close enough to the pivot point that you risk gluing the hinge permanently in place.

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Tags: repair
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# Question
Title: 9v Regulator Power Question, 1 enough or multiple?
I have 2 questions:

1. For a big 9v train layout, do you need more than one regulator to power the whole track without a shortage of power?
2. If a 9v layout was to have more than one regulator wouldn't it be inconvenient to control the speed of the extra regulator that is further away or do people just extend the 2nd regulator to be close together?

# Answer
> 2 votes
It is never a good idea to electrically connect two regulators to the same piece of track. You could damage both of them! I assume you are referring to voltage drop (and thus reduced power when the loco is a long way from the regulator input. The problem is due to the fact that the electricity is carried through steel which has a higher electrical resistance than copper. The best solution is to feed the power from the regulator along sufficiently thick copper wire to several points along the track. The loco will then see very close to the regulator output voltage no matter where it is on the track. I hope this helps.

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Tags: trains, 9v
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title: Classic 9V battery box current limiter?

text:
# Question
Title: Classic 9V battery box current limiter?
Recently I disassembled a classic 4760c01 Electric 9V Battery Box Small Complete Assembly to see what was inside.

Battery Box:

Disassembled:

In the switch component, we find what appears to be a current limiter:

It slides right out if you use a pin or something to push it out.

Here is a closeup on it with one of the other pieces:

It's a small metallic looking disk with a black edge and some divots on the faces, and no identifying or informational markings.

Based on usage experience, I *believe* it limits the current to less than what a 9V battery can actually output, but I don't know for sure or how much that limit is. I've search around, but wasn't able to find any information on the current limiters in the battery boxes before the one from 2006.

Does anyone know what the current limit of this old battery box is? Or know a way to discover what the limit is?

# Answer
> 8 votes
The short answer is **about 150mA**.

# Electrical Characteristics

From the limited testing that I've done, the component you pointed out appears to be a positive temperature coefficient thermistor. Here's how Wikipedia describes their use as current limiters:

> When first connected to a voltage source, a large current corresponding to the low, cold, resistance flows, but as the thermistor self-heats, the current is reduced until a limiting current (and corresponding peak device temperature) is reached. The current-limiting effect can replace fuses.

I only have a basic multimeter and a few fixed voltages handy at the moment, so I'm not able to derive the precise characteristics of this device. I was able to measure the following:

* Open circuit resistance is 4 ohms
* Short circuit current at 12V is ~50ma.
* Short circuit current at 10V is ~50ma.
* Short circuit current at 8.3V is ~60ma.
* Short circuit current at 5V is ~100ma.
* Short circuit current at 3.3V is ~120ma.

The tolerances on these parts are pretty loose, but for mine the maximum it can supply consistently in series with a motor is about 150mA. If I keep current above this for long, the thermistor begins to heat and total current decreases due to the limiting.

It might seem odd that the max constant current I was able to sustain is greater than the short circuit current, but this is due to the fact that this component is effectively limiting the amount of *power* it dissipates, and not the amount of *current* it passes. Power is the product of current and voltage, so because some voltage is dropped by the load, it is able to handle a current higher when loaded than it is able to when shorted.

# Physical example

As a point of reference if milliamps aren't very familiar to you, in my testing I was able to cause the clutch gear (60c01) to slip indefinitely on 43362c01 with the thermistor in series.

This drew about 100mA for me. So, you can drive most of the lighter 9v parts just fine. The current limiting will kick in at about half the stalled current for most of the motors. Larger PF motors, and especially the RC buggy motor, will not be able to reach their full potential with the overload protection in place on this battery box.

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Tags: piece-information, electronics, 9v, battery
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# Question
Title: Is there a tool that can consistently remove hundreds of 2x2 Tiles?
I have hundreds of 2x2 Tiles that I use to create LEGO City scale footpaths and floors. They are arranged in a grid on baseplates in a similar way as shown below:

Recently I had decided to rebuild the entire city and I've struggled to find a way to easily remove all the tiles. For some of the larger baseplates, I can make it easier to remove tiles by slightly bending the plate so that they pop out.

I have been using the chiseled end of the orange brick separators to remove the pieces. They work perfectly when new, unfortunately the chiselled edge is quite soft and it bends quite easily, becoming almost useless over time.

The other end of the brick separator is even harder to use and I have tried the old grey brick separator also.

Do you have any recommendations for tools (LEGO, 3rd part or non-brick based) for removing these pieces?

I would prefer not to use anything metal or that may damage the bricks.

The tool should also be comfortable to use for removing many pieces.

# Answer
Try using the orange brick separator upside down. This is a trick I learned from someone who professionally works with LEGO. The lower angle makes it easier to go under the lip of the tiles and it is much less damaging on the brick separator, as you are more pushing and sliding rather than digging and prying.

To be clear, instead of holding the brick separator with the LEGO logo and the Technic pin on top, turn the brick separator upside down. You will notice that this transforms the angle of the tip into a little ramp that you can slide under the lip of the tiles.

For flat tiled surfaces, like the one on your picture, the upside down brick separator works very well, with very little (if any) damage to the brick separator. However, notice that this method also requires more space, as the brick separator needs to lie more flatly against the surface. For tighter spaces, like when you have a wall around the tiled surface, you would still use the brick separator right side up, as the different angle of the tip requires less space for removing tiles. Once you freed up enough space to lie the brick separator more flat, you may turn it upside down to work on the rest of the tiles.

The brick separator really is a well thought out tool that works for almost all scenarios when you need to separate LEGO elements. If you find it not performing so well one way, try from another angle, or upside down, or two brick separators together, and you will likely find it working much more efficiently.

EXTRA TIP: For very tight spaces, the LEGO minifigure accessory crow bar works very well for removing tiles. The tips on the two ends are different, and can be used at different angles. The only issue is that the tool is quite small, and for people with large hands it can be a bit difficult to maneuver.
> 12 votes

# Answer
I haven't tried these myself, but in the computer repair world there exist tools with similar purposes.

# Spudger:

Flat edge (the right-size comes to a flat point):

Knife-shaped edge:

# Opening Pick/Guitar Pick:

**NOTE:** A number of companies manufacture these, but you would need to make sure you get ones that are sharp-enough to catch the lip on the tile.
> 6 votes

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Tags: disassembly, tools
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# Question
Title: How to build a car that stops at a certain distance?
I want to build a small car that is about 200 grams. I want it to run the following course and stop at exactly or about the finish line. I can't use any controlling devices or electronics.

I've an idea to count the number of revolution the wheels make to pass the finish line and the next time I stop it when it hit's it last wheel revolution.

Is there a device that can stop a wheel after a certain amount of turns? It must be mechanical and it doesn't have to be supplied by Lego either.

# Answer
> 10 votes
Here's the simplest way that I can think of to stop the vehicle at the finish line. You'll need basic LEGO Technic parts and a good length of lightweight string or thread.

Create two reels for the string. One should be connected to the wheels and the other may turn freely. Wind all the string onto the reel which can spin freely and attach the other end securely to the reel on the wheels so that it will wind up the string as the vehicle moves.

This mechanism should prevent the axle from turning after the vehicle has traveled the desired distance as long as you measure the string appropriately.

Here's an example:

Here's a similar model built in LDD showing exactly how this is put together:

The reel on the back axle will pull all of the string off of the center axle and then stop when the string runs out. If you wanted to be fancy, you could use some math to calculate how much string you need, or you could just test it to find out.

# Answer
> 2 votes
*You might consider this cheating, but here we go:*

There exist Lego wind-up motors:

With the number of turns of the key you should be able to control the distance rather precisely – unless the device gets too much momentum from the slope.

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Tags: building, piece-information, technic, design
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# Question
Title: How to estimate the pieces of a construction from just one photo?
My teacher is handing points to anyone who could guess how many pieces are in the construction shown below. I’d say there are about 350 but most people are saying thousand or more, which is insane to me. The only clues are that it is 43 cm long and 24 cm wide.

How can I best go about such a task, i.e., how can I best estimate the number of pieces from a single photo?

# Answer
In this case, knowing that the model is 43 cm long and 24 cm wide isn't particularly information. It's very difficult to give a rough average of parts when all the parts vary in size and the model isn't in a single primitive form (cube, sphere, pyramid).

With the exception of the eyes and mouth, this particular model appears to be built almost perfectly symmetrically. If you can imagine a flat plane bisecting the model in two vertically you can count the bricks on the visible side (minus the details) and duplicate that number to get a rough guess.

The model could be mostly hollow, but there are bound to be certain pieces that you don't see on either side of the model that add to the physical structure. In particular the bricks that attach the eyes and mouth and the SNOT details on the arms.

In some places it can be a bit hard to visually count the bricks (particularly around the mouth). You can use basic image editing software to sharpen the image and get a clearer idea of how many parts are used.

There are also some unusual aspects in this model where three pieces have been used where a single 2x4 brick would do as shown at the top of the front side of plant pot.
> 5 votes

# Answer
Couple of observations:

1. I do not understand your teacher's motivations in giving out this exercise. There is too much guesswork involved to make the exercise of any educational value. Example: there is no visibility into the internal frame of the main "stem" of the cactus, which is clearly a SNOT build made of several layers of plates mounted on an (invisible) core supporting structure.
2. Luckily, just putting in a guess is going to give you points, as the exercise is "My teacher is handing points to anyone who could guess how many pieces are in the construction shown below". Nowhere does it state that points are only handed out for correct guesses, so just guess any number and you should be fine.
3. You have no insights into the back of the structure. This could be a mirror of the front (as suggested by @Ambo100) but it could also be constructed differently, without any way of telling. Similarly, you don't know if the pot structure is hollow or solid, or if the reddish brown earth is one plate or several layers thick.

In conclusion, either the teacher is trolling you, or you are trolling us with this question.
> 1 votes

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Tags: challenge
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# Question
Title: Colored balls detectable by EV3 color sensor
I'm looking for large balls in standard Lego colors that are detectable by the EV3 color scanner.

So black, white, green, brown, yellow and blue and between 5 and 10 cm.

I'm aware of the Duplo balls:

But they do not seem to exist for all the 7 colors.

Are there any other larger balls from Lego in the standard colors?

Is there any third party offering them?

How much can the colors differ from the Lego colors so that they are still detectable by the EV3 color scanner?

# Answer
> 5 votes
There is an interesting discussion on this on the lejos.sourceforge.io forum.

> the calibration values for the NXT sensor are set in the factory and seem to be different for each sensor (which implies that there must be a reasonable amount of variation between different sensors). On the NXT the RGB values are true raw values and the calibration adjustments used to identify Lego colors are made in the leJOS driver.

But on the EV3 there is no calibration, and the sensor RGB mode

> is not well documented and was not exposed at all in the first version of the Lego software...So the bottom line is I doubt if anyone outside of Lego (and maybe NI) knows if the RGB values are raw sensor readings or if any sort of calibration data has been applied

So it doesn't sound like you will have a consistent set of data anyway - I'd suggest just seeing what coloured balls you can get cheaply and just trying them.

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Tags: ev3, piece-information, colour, balls
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# Question
Title: Can I use the old 4.5V and 12V blue/gray era rails with newer trains?
I have a bunch of old 12v track.

I am looking to get my son into LEGO, but I am thinking of getting the remote set so we can expand it some more.

My question is, can I connect the new track to the old somehow, and do the new trains fit the old track?

# Answer
You can absolutely run RC and PF trains on 12V track. You can leave out the center conducting rail since it won't be delivering any power to the train, unless you are planning to run both 12V and remote trains.

The main LEGO train sets have all used the same rail gauge, which is the main thing that matters.

If you'd like to use both your 12V track and the new RC track that you get, they can be joined together in various ways. Here's an example from a LUGNET thread:

There are also a few places where you can get third party adapters if you'd prefer to go that route.
> 14 votes

# Answer
All LEGO train tracks have had the same gauge, so newer trains will fit old tracks, including 12V/4.5V. Since the wheels themselves are not exactly the same, you may run into some small issues at points, but it should be OK most of the time - and using RC track wouldn't fully prevent the issue anyway. (If anything, I suspect trains woudl actually derail more on RC track than 12V)

As for connecting tracks, it's not impossible but will require some work. You can either place the track as close as possible to each other (usually using a jumper plate as the closest you can get is half a brick away). If you do this in a straight line, the train should have no difficulty rolling on the gap. Another solution would be to cut a RC track piece in half. Of course, LEGO modification is usually not something we discuss a lot here, but there are a lot of people doing track modifications, and usually for much more complicated goals.

In any case, your best bet is probably to have a full 12v layout and then have some RC parts branch off it rather than mix both systems all over the place.

I wouldn't say that 12V is superior, to be honest. There are definite advantages: the remote control of points and signals is certainly fantastic, and the more compact point design makes for more interesting layouts, especially in stations.

However, the setup is longer, parts are more fragile (which was true even when the parts were new) so you don't want to change your layout too often (from a kid's point of view, RC or 9V is much much more easier for that; track geometry isn't always easy to manage (even something as simple as using a pair of points around a 90° turn won't work) (while RC now has the flex-track which basically mean you won't have any geometry problems at all any longer); electric contacts are notoriously hard to maintain in good state (especially if you need to clean up all the electric track inserts you have).

All in all, using 12V is great if you have some, but I wouldn't bother pursuing it and trying to acquire new parts. The good thing is, if you're going to have both together, you'll get a better opinion yourself of how good they play together. In time, you could also consider abandoning 12V altogether, and if you want to go as far as reselling your collection, it shouldn't be a problem.

Frankly, the main issue with RC is the lack of automated points, but even for that there are custom solutions, even pneumatic ones. Signals can't be used with non-conductive track either (using 12V signals on 9V tracks would be very easy though); but with a RC train I'm not sure that makes a lot of sense.
> 9 votes

# Answer
As I have a 3D printer I just printed up a number of track adaptors like this. It works well. The print files are available free from "Thingiverse".
> 1 votes

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Tags: trains, compatibility, 12v
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# Question
Title: Can you interchange System and Technic LEGO?
My grandson would like to motorize his LEGO builds. Does the Technic motor pack only work with Technic LEGO or can he mix it with the regular sets that he already has?

What should he start out with?

# Answer
I assume by the Technic motor pack you mean this:

The straightforward answer is in my opinion "no", the pack does not contain enough pieces, nor do System sets contain enough unless they were explicitly designed to have moving parts and allow motorization (e.g. the carousel or other LEGO expert fairground sets)

You need "some" LEGO Technic to allow for moving parts. The LEGO Technic itself is then in many ways compatible with System Lego.

The amount of Lego Technic your grandson will need depends too much on what he wants to achieve to give a generic answer.
> 5 votes

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Tags: compatibility
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# Question
Title: Lego Mindstorms education NXT 9797 software for a MacBook Air
Where can I find Mac OS compatible software for the Lego Mindstorms Education NXT Base set (9797)?

# Answer
> 3 votes
You can download software for programming the LEGO Mindstorms NXT robots on macOS directly from the LEGO Mindstorms website.

The software is packaged in an ISO image, and there are instructions for how to install it also available on the same page.

Keep in mind that this is the retail version of the software, designed for use with the 8547 NXT 2.0 set, not the education version. The programming functionality for both sets will be the same, but the retail software does include some features specific for the 8547 set, such as building instructions, and does not include some features that the educational software does, such as data logging.

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Tags: mindstorms, nxt, software, education, mac
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# Question
Title: What strategy should FLL teams use to pick their next robot mission?
FLL teams compete by running their robot on missions. The robot leaves the base, does a task, and then returns to base. Each mission is worth a few points. The goal is to collect the most points in a 2 and 1/2 minute run.

The tasks are at different positions across a 4' x 8' obstacle course.

Some missions are easy, others very difficult.

Some missions require intricate Lego constructions. Some require difficult programming. More than one task can be accomplished before returning to base.

What strategy should an FLL team use to pick the missions to attempt?

Given there are about 15 missions that each take somewhere from 10 to 30 seconds to run and the team has 5 missions that work most of the time and the 5 missions consume the 150 seconds available, what should the team work on next?

# Answer
First off, that website is horrible, so much clicking on expandable things, a terrible UI.
The PDF download of the rules is better.

Looking through the missions I notice a few things:

* None of the missions have significantly bigger point values to make them obvious choices over other missions.
* The missions are all based on end state and cannot be repeated for multiple points

So it appears you should simply try to maximize the number of successful missions accomplished in the limited time period.

Some missions should obviously be combined since they are handling similar pieces and would be easily doable with the same robotic manipulators.

Such as:

* Moving pipe sections for: pipe removal, pipe install, pipe construction
* Moving Big Water pieces for: fountain, flower, and water collection
* Manipulation of levers or handles: flow, water treatment, faucet
* Picking up, moving, and aligning pieces in the field: pump addition, rain, manhole covers, sludge, water well
* Moving objects from the base onto the field: tripod, water well, slingshot

Also some missions must be done before other missions:

* Manhole covers removed before a tripod is placed
* Pipe removal before pipe install

The best bet is to pick a group of tasks that a single robot build is likely to be able to do well and go from there.

Some thought might be given to completing the furthest missions first, so that traveling past already completed missions doesn't mess something up.

You might start by sorting the task into groups like I have done, try to judge the inherent difficulty of the mission, and rank them comparing with point totals.

On a final note: As this is a competition for children to learn about engineering and robotics, you should really just explain the rules/different objectives/point values and help the kids pick a strategy themselves. The planning process itself is as much engineering as the programming and building of the robot.
> 1 votes

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Tags: fll
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# Question
Title: What are the differences between NiMH and Alkaline batteries for the EV3?
Currently I am using six rechargeable batteries for my Lego Mindstorms EV3.

A few seconds after I start a motor the EV3 gives a notification that that the battery is low.

I know that good batteries are alkaline ones. However, personally I want to avoid using them because I will need to throw them away after use.

# Answer
> 9 votes
NiMH batteries only provide 1.2V per cell whereas Alkaline batteries provide 1.5V (nominal values). This means that new/fully charged batteries will provide a total of 9V for Alkaline and 7.2V for NiMH. The EV3 is programmed to show low battery somewhere around 6.2V and turn itself off around 5.5V. There is no option a available to tell the EV3 the difference between these two types of batteries. The EV3 was designed for Alkaline batteries. You won't get good performance from NiMH with the EV3.

LEGO also makes a rechargeable Li-ion battery pack. Being designed for the EV3, this battery is properly sized for comparable performance to Alkaline batteries. Be aware though, that this battery pack makes the EV3 one LEGO beam width taller, which could require some models to need to be adjusted to accommodate the extra size. Also, when you remove the batteries from the EV3, you will notice a small black circle in the battery compartment. This is actually a button that lets the EV3 know that the battery pack is installed rather than regular Alkaline batteries. This lets it adjust the battery gauge and low battery alarm for the slightly different voltages of the rechargeable battery pack.

# Answer
> 0 votes
Another possible choice of batteries are lithium-metal batteries like Energizer Lithium Ultimate batteries. The performance to price ratio is better than premium alkaline batteries but worse than discount alkaline batteries (which often perform quite as good as the premium brands). I use them mainly because I can't be bothered by replacing batteries too often. Also their voltage level stays nearly constant until their charge is depleted, which is definitely not the case for alkaline batteries. For alkaline batteries the EV3 starts complaining while there is quite a bit of charge in the batteries left.

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Tags: ev3, electronics, battery
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# Question
Title: How to unplug black friction pin connectors
Black friction pin without slots connectors are common in older Technic sets. Note that these were quickly replaced by the current version with slots that is much easier to remove.

vs

Especially in older sets, it is not uncommon for these connectors to get completely stuck (as if glued) in bricks with holes. I have to resort to pincers and brute force. This typically results in the connector being damaged.

The orange brick separator is often not tough enough to do the job.

So, how can you separate these things?

# Answer
> 8 votes
It depends in what type of beams the pin are mounted.

1. For studless Nicael's methode is the easiest. Otherwise you can use method 3
2. For studded beams you can use variation on this methode. take a axle of 6 or 8 long, 5 or 7 other beams and some plates. Stack the beam side by side and lock them together with the plates. Place the beam with the pin on top pin sticking out. Place the axle in the hole under which the pin is located. The axle will stick out 1 stud. Puch this on a hard surface that is allowed to be scratch / dented. This will remove also pins that are deformed.
3. If the pins are in other parts you often can move them to a studded beam by pushing the other end in a studded beam and putting in a minifig tool, like a broom, shovel or light saber blade.

Loose parts:

Half assembled:

Axle placed:

Pushing pin out on table:

Switching to a beam:

# Answer
> 8 votes
Take your cross axle:

And push it into the hole where your pin connector had stuck

# Answer
> 6 votes
Here is an alternative 'pin-pusher' that I put together using as few pieces as I could (except for a few tiles to make it a bit more intersting).

The blue pin near the centre pushes pins out half way, just enough to remove the pins by hand and not to far for it to pop up out in the air.

The two tan axles help to align the Technic beam you are using, I find they are most useful when you are trying to remove a long row of pins on a single beam.

It is also quite good at removing double pins with axle holes.

You *could* use some blue-tac to keep in in place but I don't think it's necessary.

# Answer
> 4 votes
I have resorted to brute force in the past. By which I mean destructive removal of the pins. I use a Dremel tool with a 2mm drill bit or 3mm router bit to carve away at the pin until it disintegrates.

The new style pins sell for about 0.3c each on Bricklink, so if you're assembling a model it makes sense to just buy a pile of new pins and and use those instead. I use the pins as "stuff" for my construction models to work with, so I bought 10,000 pins in one hit for about $50 including delivery. It's just not worth putting the old pins into newly assembled models when it's so cheap to avoid the problem.

To actually remove the pins when they are stuck I use the approaches other people have given. When they fail I use olive oil as a lubricant (soak Lego in oil, wait). That's much easier if you can keep the end you're going to be pulling on out of the oil. Then use the "jam a bar into the end" technique to lock the pin into another Lego beam and pull it out. Usually twisting is required.

But I have to admit that I don't bother any more. I pull models apart, and pins that I can't get out with my fingers I just drill out. If I really have to I'll buy more old-style pins on Bricklink, but I have enough friends who buy second hand Lego and hate those pins that my supply is adequate. And I'm happy to give away the new style pins in exchange. Again, they cost me 0.5c/pin...

**The old pins are brilliant** if you're exhibiting a model and it has parts that tend to fall apart. Use the "stuck forever" pins and things don't fall off nearly as easily. It's legal, so you can still put the "Model is 100% unmodified Lego" sign on it whereas if you use glue you can't do that.

# Answer
> 3 votes
I used to use the longest Technic axle I could find. The axle would be uncomfortable to use for dismantling large LEGO sets with hundreds of Technic pins as it would always dig into my palm when I forced the pins out.

If you push one or more 2x2 Round Bricks into one end with a 2x2 Round Plate (with or without a rounded bottom) you have a nice handle which is a bit more comfortable to use.

When you place it down on a table it will never roll off onto the floor.

You can also change the colour of the handle to make it easier to find.

# Answer
> 2 votes
Everyone has come up with a solution, but I do not understand whether I am missing something or if I actually know something others do not.

There is a LEGO piece made precisely for this. It is the Technic separator.

# Answer
> -1 votes
I've used tweezers since I don't have an axle rod in hand.

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Tags: technic, tools, disassembly
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# Question
Title: What is the length of a DUPLO train bridge?
I'm trying to plan a DUPLO train track layout to order but I currently don't own any pieces. I'd like to include a bridge like the one in set 3774, but I'm unsure if it will fit my layouts.

Can anyone tell what's the length of the bridge (it seems to be made up of parts 6393 and 6392, two of each) in DUPLO studs?

# Answer
Based on the layouts from this answer, a half-bridge seems to be 2 straight tracks + 1 quarter-circle (split mid-track at the end, because the middle of the bridge is centered with the crossing track below it).

From this guy's measurements, a quarter-circle of the newer DUPLO tracks is about 18x18 studs. Straights are 8 studs long.

So, a half-bridge should be 32 studs (16+8+8), or 4 straight tracks. The full bridge would be 64 studs, or 8 straights.

**Note:** I don't have the pieces to confirm these measurements.

**Note 2:** I now have the pieces and can confirm these measurements, as shown in the picture below.
> 9 votes

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Tags: trains, duplo, bridge
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title: Can ScratchJr work with WeDo 2.0?

text:
# Question
Title: Can ScratchJr work with WeDo 2.0?
Now that ScratchJr is available on the tablet.

Is it possible to use it to control a WeDo 2.0 robot?

# Answer
No, you can use only Scratch 2.0
> 2 votes

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Tags: wedo, scratch
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# Question
Title: What sets have the best price per part ratio?
I am trying to get the set LEGO makes with the best price per part. I could spend the next hour calculating it or I could ask someone who has already done this.

To clarify, I am buying any new set at retail price from LEGO. I will wait until there is a good promo running, but wanted to know ahead of time. I don't care about the pieces just the price per part.

# Answer
> 14 votes
Not going to argue with the reason for the request, but here are some options that give (close to) the best price per part:

1. Any classic brick box typically gives you a less than $0.05 per part price. Getting those on discount can get you even lower. (E.g. 10704 when on sale at WM in the US was $20 for 900 bricks - or a little over $0.02 per brick).
2. Special sets not for regular retail (marked as Gear on Bricklink.com) have a good price per part ratio. 40174 Chess set has over 1400 pieces and retails for $55 (~$0.04 per part). Only available at LEGO Shop at Home and LEGO stores. Similarly for the What Am I? game - 540 pieces, currently on sale for $24, so also ~$0.04 per part.
3. Some smaller sets, especially when on discount, also have great price to part ratio. 100-120 pieces in a $5 set gives a price to part ratio of $0.05 or better.
4. On the other end of the spectrum: LEGO has released quite some large sets recently with great price-per-part ratios. Sets like Destiny’s Bounty (2300 pieces for $160, Ninjago City (almost 5000 pieces for $300) and especially Saturn V (almost 2000 pieces for $120) are expensive but proved tons of pieces.
5. Clearance discounts (especially those of 70% or more) are great opportunities to buy high piece-count sets for little money. For example the Imperial Assault Carrier from 2014 was available at WM clearance for $30 or less, and has 1100 pieces.

Brickset has a cool feature where you can see all sets in a Theme or in a given year sorted by the Price per Piece count. First, go to the page for the year you are interested in (I chose 2017). Then use the sorting dropdown to pick “Price per Piece (US)”. You can see that this largely validates my points above. Note that the list starts with many sets that do not have a price per piece in US dollar available (promos, limited release sets, sets not available in the US etc.) You will have to scroll quite far down before the proper list starts.

# Answer
> 6 votes
Phil B has some great info posted, but here are some additional things to think about.

Anything can go on clearance, and obviously adding 50% off will help the price per piece. However, sales and clearance are unpredictable in that you don't know when the sales will occur or what they will be comprised of. So I would skip doing calculations about hypothetical sales, unless you have a 70% off set in your hands.

Phil B made no mention of the Lego Pick a Brick wall. This is, for many types of pieces, the absolutely most cost effective way to get a lot of parts. If you live near a LEGO store, swing by once a month or so and load up on bulk parts.

He also talks about 'classic type' sets. This would be the Creator Line sets, which have the added bonus of having a lot of good basic pieces that aren't too specialized. Look at these first, they are going to be your best bet.

The really large sets tend to be very cost effective too, but it might not be in your budget to drop $150+ per box.

If you really want a lot of LEGO cheap, go buy 50 lb. used lots off of e-bay. Even after you pick out and throw away the inevitable mega-blocs, the price per piece is still way lower than anywhere else.

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Tags: shopping
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title: Identify LEGO Dimensions pack

text:
# Question
Title: Identify LEGO Dimensions pack
Can you please help me figure out which character this build pack goes with?

The bag has a copyright date of 2007. I know the number on the bag doesn't matter but I noticed the copyright date might help narrow it down a bit.

I've also included a picture of the set laid out so you can see which pieces are in it.

# Answer
Based on the Trans-Yellow Plate, Modified 1 x 1 with Tooth Horizontal

which appears only in three sets this is:

71264-1: The LEGO Batman Movie: Play the Complete Movie
> 6 votes

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Tags: set-identification, lego-dimensions
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# Question
Title: amazon.fr hints that the Boost app will be available on phones?
At this moment (end of the year, 2017), the description for Lego Boost on the french amazon site includes the notice:

> Enfin, l'application sera également disponible sur smartphones dès les vacances de fin d'année.

(translates to: Finally \[it's after the list of compatible tablet Os'\], the application will also be available on smartphones from the end of the year vacation.)

Has anyone read anything about this elsewhere? I'm failing to find anything on google, the LEGO site or the German or UK Amazon sites.

# Answer
V1.4.4 on Apple App Store state “support for mobile phones”, and it does install fine on iPhones. Finally.

V1.4.3 on the Google Play store also lists "support for mobile phones" in the "What's New" section and can be installed on my Samsung S7.
> 4 votes

# Answer
Installs and seems to run on my smartphone (galaxy A5), but haven't opened my boost set yet to verify further. I think lego indeed recently started supporting smartphones.
> 2 votes

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Tags: software, boost
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title: What is the LEGO EV3 rpf file?

text:
# Question
Title: What is the LEGO EV3 rpf file?
I read the LEGO Mindstorms EV3 Communication Developer Kit's document.

I have a question in 4.2.1 (Start program “Demo” on EV3 brick) it is mentioned "The file-extension is "rpf" and NOT "rbf", so how can I generate the rpf file?

# Answer
> 6 votes
`rpf` stands for "rudolph program file" \[source\] (I believe "Rudolf" is the internal code name for EV3.)

These are the files created using the "Brick Program" utility on the EV3 brick. Once you have created a program on the brick, you can upload the file using the EV3 desktop software. You can find the files in the `BrickProg_Save` folder.

However, after explaining all of that, I think the documentation you linked may be a bit misleading. The file extension does not *have* to be `.rpf`. The file just has to be an EV3 bytecode file, so a `.rbf` file could be used too. They probably just chose that example since the `Demo.rpf` file is installed by default on the EV3.

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Tags: ev3, software
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# Question
Title: Looking for a set based on random pieces with grey marble texture plastic
My son received three, gallon-sized, ziplock bags full of random LEGO's for Christmas. I've been scanning the interwebs for unique pieces in hopes of finding some of the kits and instructions for some of the more interesting (to me) pieces. I've been searching all over and hope to find some direction in this forum. I've attached a picture of some of the pieces which look to be part of a spaceship, maybe. Also, there are some numbers stamped on the inside of a few of them such as AM72433, AM18902, and AM76367. I've searched for these piece numbers as well but I can't seem to track them down.

# Answer
> 6 votes
X-27's comment is correct, I have 40 years of LEGO collecting under my belt, and I have never seen any bricks with a speckle pattern like that.

You might go through the bricks you got, knock off bricks are very easy to spot once you have seen a few. Cheap looking plastic, dull colors, lack of Lego logos (almost every single part Lego makes is stamped somewhere) are all signs of knock-off brands.

If you want to search for sets based off of real Lego parts, try: https://brickset.com/, they have a part catalog of pretty much every set ever made that you can use to look stuff up.

Here is a random part I pulled up to show you: https://brickset.com/parts/74335/mini-antenna-ass-red-bla

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Tags: set-identification, clone-brands
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# Question
Title: What can I do to clean a minifigure's torso?
I have the old General Grievous figure from 2005, and it is almost 10 years old.

Due to its age, the torso now looks yellow-painted.

What can I do to clean it?

# Answer
In general, legos can be un-yellowed by soaking in a combination of hydrogen peroxide, oxyclean powder (or sodium percarbonate), under sunlight or UV light. Or use Retr0Bright. Certain colors of painted decorations (such as gold) will not hold up well to the cleaning, but plain pieces and some colors do hold up well.
> 3 votes

# Answer
For regular dirt and grime a little bit of dish soap and warm water and a sponge or soft cloth should get most figures clean. For tough or caked on dirt you may need to use a scrubby sponge or soft brush, but be you run a risk of damaging printing on the figure. Older LEGO pieces can become yellowed over especially with prolonged direct exposure to sunlight. Many have reported success with oxidizers such as hydrogen peroxide or oxyclean, but there is also a possibility of damaging the element. Good luck!
> 1 votes

# Answer
Adding to user3576's comments:

Dish soap and warm water is your first choice. You can let tough grime soak in soapy water for weeks before washing if needed. Hot water is bad because ABS has a (relatively) low melting point, so a trip through the dishwasher would not be advised. Also, dish washing detergent has abrasives, so...double nope.

Yellowing due to sunlight needs oxyclean + h202 or retrobright to correct. This works, but in addition to the above warning about metalics, be aware that it take a LONG time to work, so don't expect a quick 5 min dip will start to fix things. I have left bricks soaking in the stuff for weeks.
> 1 votes

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Tags: minifigures, cleaning
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# Question
Title: Are there LEGO plates without the word "LEGO" on the studs?
I came across this image of the "LEGO Stack Overflow Hat" which is a hat made out of LEGO.

The individual who made the hat asserted, "it's 100% LEGO," but if you look closely at the hat, you'll see there are plates on it which do not have the word LEGO on them.

Since it is ostensibly 100% LEGO, what LEGO plates have studs without the LEGO logo on them?

# Answer
There are no LEGO parts with studs that have no logo on them. The hollow versions of studs which are on technic bricks and many other bricks have the Lego logo printed on the insides.

As someone that goes through a lot of used LEGO, I have found that there are some parts that have been worn and the logo is not nearly as visible as it would be brand new. That said, I have never seen any part be worn to wear the logo has been smoothed out. The ABS plastic that TLG uses for normal system parts is quite hard and would really have to take abuse, not just playwear, to get to a point of smoothness on the studs.

In this individual case, if you look closely at any point in the picture, several parts appear to have smooth studs. This appears to be consistent on many of the parts which would certainly not lead the conclusion of wear. Furthermore, even from the relatively grainy photo, the coloration/shine of the smooth studs parts just seems off...

In any case, it's nearly indefinitely false that the hat pictured is 100% made of LEGO parts.

EDIT:

Upon the added pictures from the creator, it would appear I am wrong. While most of what I said still stands true, I underestimated the power of bad lighting! I've seen some photos that distort the look of LEGO, but never to this extent! I stand corrected.
> 18 votes

# Answer
What you are seeing is actually the result of poor lighting, somewhat worn bricks, probably camera app noise reduction, and perhaps image compression, although if you look really closely you can kinda see it's a little darker where the lettering is.

As the creator, I promise that every piece in the hat is 100% genuine LEGO pieces (no knockoff brands). Unfortunately, when I took the picture the sun had set, and all I had was some weaker household lighting.

Here's another shot of the front with the face turned towards the lighting, so the lettering will catch some contrast.

The 2x2 plate in the bottom left does have more-pronounced lettering than the older 2x10 plate next to it, which is why you are able to see it better in the other picture.

---

To answer the question of are there plates that don't have "LEGO" stamped on the stud, no there are not to my knowledge. Even the very first LEGO plates have the stamp. Some special plates do have hollow studs though.
> 54 votes

# Answer
There are a (very) few official LEGO elements that don't have the logo stamped on the studs. the new 1x1 dots for example, have a hole through the center, and as a result don't have the logo. In a similar vein, there are a few window frames that had similar indented studs that have no logo.

An overwhelming majority of LEGO parts have the *LEGO* logo stamped somewhere on the piece though, often in some unobtrusive spot. While there are elements that have no official branding on them at all, they are rare.
> 9 votes

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Tags: part-identification
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# Question
Title: Why are these hinged plates slightly different colors?
Something I've noticed is that certain pieces appear to be slightly different colors for other pieces of the same color. In particular, hinged red pieces seem to be the most noticeably different, especially some versions of the red hinge plate.

As you can see, half of the hinge plate is quite a bit darker than the other half which matches the regular plates. The 1x2 fork clip piece is also a little darker, though not as much as the hinge plate and it's hard to see in the picture. I remember that hinge plate being that way when I got and 3 others in the 10167 Brickmaster Kit (with Digital Designer CD) back in 2004, so I don't believe it was faded or a defect.

So I've long wondered, what's the deal here? Are the hinged plates made of different plastic, like the transparent pieces are?

# Answer
Quorneng's answer is spot on, even bricks that were from the same set might have been made from differing batches of a particular color and slight variances will produce differing colors. Purple is the most notorious Lego color for having a great deal of variance between bricks, and red is not surprisingly, also inconsistent at times.

To add to the mix, Lego is changing its formulas over time to keep costs down, and to make the bricks more durable and consistent. Earlier ABS bricks where stiffer and more brittle than modern bricks. They have more of a tomato red color, and are easy to spot next to modern bricks.

UV damage can alter the color of bricks over time, although this can be fixed with oxyclean + h202.

Finally, I believe that Lego will internally recycle 'bad' batches of bricks, grinding up and melting down ABS from lots that don't pass QA. This probably also affects brick color. I had a friend who made the pilgrimage to Billund to see the main plant. He told me about how they have a display that shows the casting of bricks to visitors, and it re-uses plastic for the demonstration. I recall that he commented on how the plastic colors were slightly odd looking, presumably because it had been recast so often. This makes sense to me, but it is a second hand story, so don't cite me for your thesis...
> 7 votes

# Answer
The colour of virtually all plastics, like paint, is an 'added' pigment so it is difficult to maintain exactly the same colour. As others have pointed out some pigments are more susceptible to the effect of sunlight than others - red goes pale - white goes yellow.
> 5 votes

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Tags: piece-information, colour, plastics
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# Question
Title: Why do LEGO bricks yellow at different rates?
So, here is my LEGO Space Shuttle. Originally built in 1991, never disassembled (unlike the rest of my sets), so all parts are original and all were exposed to the same amount of sunlight.

However, the amount of yellowing is highly variable. The hinge for the manipulator arm (just back of the windshield) is like-new white, and the alignment pin for the arm (just in front of the green brick) isn't much different.

Two of the wing panels are much whiter than the others, and although it's hard to see, the hinged parts towards the back are two distinct shades of yellow.

What's the reason for this?

# Answer
There are several reasons for this:

1. There isn't just one formula for the ABS plastic that is used in LEGO. There are actually quite a few. Depending on the color, translucency, and function, the mix of materials will vary.

Translucent pieces are quite a bit harder and more rigid than other Lego bricks. Mini-figure accessories tend to be quite a bit softer than other pieces (so they don't cause internal damage if/when swallowed).

If you pull out several types of parts and pay close attention to the hardness, flexibility, and stiffness, you will notice that not all LEGO is made the same.
2. Even for similar parts, there is variance in the chemical mixes. When you get a set, it is highly likely that the parts weren't made from the same batch of plastic.

Mixing plastics with minor variations can cause changes in the rates of UV damage and discoloration. It is really hard to get perfectly matched colors across multiple batches of plastic.

The fact that LEGO colors are so consistent is due to the fact that they have really high standards for quality control.

Oh, and if you want to restore your set to that new pristine white color, you can treat it with retrobrite or oxyclean and hydrogen peroxide. There are plenty of articles online if you do a quick search for either.
> 5 votes

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Tags: colour, plastics
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# Question
Title: Can the BrickStore part database be updated?
Is there a way to update BrickStore database with new element numbers, sets, and pictures of the elements? How would you do this?

# Answer
I found this on Eurobricks from 2014:

> I recommend to try BrickStock instead of BrickStore. Brickstore is old and is no longer supported and updated. BrickStock is a fork (using the source of BrickStore) of brickstore.

I use Brickset.com which is very up-to-date and suits the needs of me and my sons.
> 3 votes

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Tags: software, inventory
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# Question
Title: Is it safe to overload LEGO train motors?
When I was in Fana'Briques in 2008, there was a speed record competition for TGV-themed train. The setup used a section of custom-made straight track (aluminium rails if I remember correctly) and was powered by a custom transformer which could deliver higher voltages than the standard LEGO ones.

As ar as I recall, they went up to above 30v, and there seemed to be more damage to bricks (one train did derail dramatically, and pieces flew everywhere) than to motors.

Is it safe to overload LEGO train motors that way? I assume 30v is pushing it too far, but what could be considered a safe limit that motors can endure for an extended period of time?

I'm speaking of regular 9V motors, but answers for other LEGO motors can be interesting too. I know Philo pushed them to 12v when testing their efficiency, but with a big warning that he couldn't guarantee the motors would tolerate it for a longer period.

# Answer
> 15 votes
> What could be considered a safe limit that motors can endure for an extended period of time?

Their rated voltage.

Motors are designed to operate at their rated voltage indefinitely, or until they wear out, whichever comes first. Exceeding this voltage means you shorten the life of the motor.

Your big enemy is heat. At some point, the amount of heat generated by the windings in the motor will exceed the ability of the motor to dissipate it, and the wire in the winding will melt and break the electrical connection (usually at the point where the wire is soldered to the commutator).

The point at which failure or excessive stress or wear occurs is influenced by many factors, including the amount of current driving the motor, the speed at which the motor is turning, the amount of load the motor is driving, the ambient air temperature, etc. These variables make it difficult to predict a safe voltage above the rated one.

In addition, over-driving motors in this way makes them inefficient; speed increases are offset by higher losses due to back-emf, limiting the additional torque, so driving motors this way eats batteries fast.

Last but not least, overdriven motors are a safety concern. The paint covering the windings can catch fire and burn down your house; you have to watch such experiments *very* carefully.

If you really want to increase the power, your best bet is to choose a motor with more torque, so that you can run it at its rated voltage.

# Answer
> 1 votes
Yes heat is the ultimate problem but the most likely failure will be from the commutator brushes. As the voltage is increased so does the heat of the sparks created as the brushes pass from one commutator segment to the other. This is a particular problem on a 3 segment commutator. At 30V even if the motors can stand the mechanical loads and heat generated I doubt the brushes would last for more than a few minutes however such a short life would be quite acceptable for a record high speed run, particularly if someone else was paying for the motors!

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Tags: trains, safety, motor
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# Question
Title: What set are these LEGO assemblies from?
I bought a lot of second hand LEGO - it was an utter bargain at £10 - and have identified loads of different sets, however this part is infuriating me as I can't identify what it could be part of. Perhaps a submarine? It looks like a periscope in the middle and I'm sure it had at one point 6-8 legs sticking out on the sides.

# Answer
Set 75013 Umbaran MHC (Mobile Heavy Cannon), based on the leg shape and the Dark Red 1x1 Headlight Bricks.
> 19 votes

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Tags: set-identification, star-wars
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# Question
Title: Red cargo ship with pier and a tower crane set?
When I was a child (~15-20 years ago) I remember I had a LEGO set composed by a red cargo ship, with a pier and a tower crane that supposedly moved blocks from the pier to the ship.

The name of the ship was Titan, or Atlantic I think.

Can someone find the name of the LEGO set and maybe a picture?

# Answer
Based on your description, the set is Launch and Load Seaport (6542):

It was released in 1991, and it matches everything you described including a ship called "Atlantic", so this has to be it. If you're looking for some nostalgia, you can pick this up on Bricklink for ~$150.
> 10 votes

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Tags: set-identification
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# Question
Title: Identify lego Set that includes a caravan
I have this set that was given to me, but I cannot locate a caravan like this anywhere. Is this part of a set or something someone just build? As you can see there are a lot of missing pieces. Does it ring a bell to anyone?

Thanks a lot

# Answer
> 10 votes
This is a small build, slightly altered, from set 4997 Transport Ferry from 2008.

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Tags: set-identification
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# Question
Title: Please identify the set or sets, grey 6 x 6 circle and dark red and white curve with vent
I have these two assemblies which I have no idea if they are from the same set or not. The black square on the round assembly can spin. Any ideas?

Thanks a lot

# Answer
> 11 votes
The build on the left is from 60002 - Fire Truck \- it's the turntable/mount for the ladder:

Based on containing the "Plate 6x6 round", and "Bottom W.Turntable 4x4"

The build on the right is from 60147 - Fishing Boat \- it's one of the engines:

It's currently the only set with "Plate W. Bows 2X3½" in New Dark Red.

# Answer
> 5 votes
The parts on the right are from 60147-1: Fishing Boat

Based on the Dark Red Brick, Modified 2 x 3 x 2/3 Two Studs, Wing End and the White Wedge 4 x 3 Open with Cutout and 4 Studs

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Tags: set-identification
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title: Is Technic compatible with Mindstorms?

text:
# Question
Title: Is Technic compatible with Mindstorms?
My wife bought me a Mindstorms NXT 2.0 for my birthday. I've been reading up on it from as many sources as possible however apart from the 9695 Education Resource Set which adds some additional bricks to the set, is the Mindstorms compatible with any other Lego sets, specifically the Technics?

If so, where can I get more information on how these sets are interchanged?

# Answer
Yes.

The current Mindstorms sets are completely Technic orientated and use the Technic pins (i.e. \[part:3673:7\]) to connect to the newer Technic Beams (i.e. \[part:32316:7\]) as well as the original Technic Bricks (i.e. \[part:3894:7\])

The various different size pins and axles are the way to interchange between these.
> 18 votes

# Answer
Mindstorms is essentially Technic and Lego parts with electronic components built in to them. So the answer is yes.
> 8 votes

# Answer
There are two sides to this, building and electrics.

In terms of building yes, mindstorms can be seen as an extension of Technic and most of the Elements in a mindstorms set will be "Technic" elements. The old RCX was orientated towards "old-style" Technic that used a mixture of pins and studs while the newer NXT and EV3 are orientated towards new-style Technic that mostly uses pins.

In terms of Electrics things are more of a mess.

LEGO has had various electric systems over the years, broadly speaking there are.

1. The 4.5V/12V system, this is ancient and completely incompatible with Mindstorms. This used plugs with two pins, sometimes with a central bump.
2. The "electric system 9V", inroduced in 1990 and used for motorising many Technic sets. Also used by the RCX. This used contacts built into the top of lego studs.
3. The NXT/EV3 system this uses a RJ style connector but with the clip in a different position from normal.
4. The "Power functions" system, introduced in 2007 and has now mostly replaced the "electric system 9V". This uses a custom connector with two lego studs and a custom contact block next to them that is roughly 1x2 but won't stack with lego bricks.
5. The "powered up" system, the newest system from Lego. Sometimes also reffered to as "power functions 2.0".

Lego sold an adapter cable to go from the NXT to "electric system 9V" part number 8528. Unfortunately it is no longer sold. They also sell two different lengths of extension/adapter cables which can be used either to extend power functions or to connect power functions to "electric system 9V" part numbers 8886 and 8871.

It seems that Lego never made an adapter to go directly from the NXT to power functions though you can connect the NXT to power functions motors by combining the two adapters above or by splicing cables to make your own adapter.

Also it seems that the EV3 is not really compatible with the Lego adapter cable, apparently sensors won't work at all and motors will only work with special software hacks. There is discussion of this and possible workarounds with custom cables at How to use Power Functions with Mindstorms EV3? and Use legacy RCX sensors with EV3

The powered up system seems to have no compatibility with anything else at least not using official parts. Lego don't even sell an extension cable that can be hacked into, I've seen some third party ones but they were very expensive.
> 4 votes

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Tags: nxt, technic, mindstorms, compatibility
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# Question
Title: Does the LEGO "Power Functions Extension Wire" (8886) work in both directions between old 9V and new Power Functions devices?
Here is the LEGO "LEGO® Power Functions Extension Wire" (8886):

We can see that the left connector can connect to *old* 9V electric bricks or wires and the right connector can be plugged to the *new* Power Functions connectors.

The LEGO website gives this description:

> Power up your LEGO® Power Functions creations with this 8" extension wire. Make your models bigger, better, and more mechanized than ever before!
>
> * **Allows you to connect your LEGO 9V electric systems to the new Power Functions!**
> * Extension Wire is 8" (20cm) long

(emphasis mine)

Does this cable work in both directions?

* Can it power a *new* *Power Functions* motor from an *old* battery box?
* Can it power an *old* motor from a *new* *Power Functions* battery box?

Do switches like the *old* one or *new* one let you control *new* and *old* motors respectively?

# Answer
I performed my own tests with:

---

Here are the results: **it works in both ways with motors and battery boxes**.

*Old* **9V** motor powered by *new* **Power Functions** battery box, with the 8886 cable plugged to the motor through the electric plate:

(the cable is out of the photo frame but I guarantee that there's no trick)

*New* **XL** motor powered by *old* **9V** battery box:

As you can see, the connectors of the 8886 cable have different colors, the 9V-side is a lighter grey.
> 4 votes

# Answer
According to *Customer reviews* on the official website, this cable enable powering motors in both ways between *old* and *new* power functions versions:

---

> This cable allows you to power the new 9v motors from the old 9v system or vise versa..

Author: heavyD.

---

But there is an incompatibility between the old battery boxes and the IR receivers:

> This cable also powers new motors from the old battery box, but it cannot power an IR receiver, which requires the new battery box and all 4 wires of the new cable. (This cable only converts the 2 motor-powering wires.)

Author: Technic010.
> 4 votes

# Answer
Power functions has four wires, "Electric system 9V" only had two. Two wires carry the motor control lines. The other two wires carry a power supply which is fixed polarity, never speed controlled and is not switched by the IR receiver (though it is switched by the switch on the battery box). The adapter cable connects the two wires of the Electric system 9V to the two motor control lines of the power functions.

Things that will definitely work:

* Powering any "Electric system 9V" kit from a power functions power source/controller. Some of the Early kit will require use of an Electric plate or an old style cable because it has it's contacts on the bottom.
* Powering an ordinary power functions motor or a set of power functions lights from an "Electric system 9V" power source/controller.

Things that definitely won't work.

* Powering a power functions IR receiver from an "Electric system 9V" power source.
* Powering the power functions servo motor from an "Electric system 9V" source.

Things I can't find enough information on.

* How the power functions switch behaves. In particular whether it draws it's input power from the fixed-polarity lines (which would make it incompatible with "Electric system 9V" power sources) or from the motor lines (which would make it compatible with "Electric system 9V" power sources).
> 1 votes

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Tags: technic, motor, power-functions
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title: LEGO Modulars Massive Inflation?

text:
# Question
Title: LEGO Modulars Massive Inflation?
What caused retired LEGO Modular sets to spike in value so much?

Any ideas or thoughts would be appreciated.

# Answer
> 1 votes
At certain times of the year (particularly at the start of the new year) LEGO release new sets and at the same time remove older sets from their inventory.

Also, in November and December in the run up to Christmas LEGO investors may take advantage of the increased demand by raising prices. Parents buying presents for their children would perhaps bid higher than usual as they are keen to get the right present and in time for Christmas.

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Tags: shopping, modular-buildings
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title: How to get leJOS to run on macOS Sierra

text:
# Question
Title: How to get leJOS to run on macOS Sierra
I am working with an eclipse plugin that requires it to run 32bit Java 6 on it and I do have Java 6 on my computer but when I run the program I get this error.

```
Error: This Java instance does not support a 32-bit JVM.
Please install the desired version.
Linking the file failed with exit status 1

```

The Java 6 I installed was from Apple's legacy Java 2015. In the installation tutorial of leJOS it said that

> Note that even if you have a 64-bit system, leJOS will always chose to run java in 32 Bit mode by automatically passing the -d32 parameter to the java command whenever necessary.

If that is the case why doesn't my program run if I have Legacy Java 6 installed on my Mac? Can anyone get it to work on their mac on this version macOS?

# Answer
> 3 votes
I've managed to get leJOS working on macOS Sierra, minus Bluetooth support. Bluetooth support is officially broken and has been for a while. There also hasn't been a new release in years, so a fix likely won't come. Otherwise it still works, if you jump through some hoops.

# Guide:

## 1. Fantom Driver:

First, you need to install the "Fantom driver". You can find on the Mindstorms download page.

Extract that ZIP, and you should have a installer package named `MAC legodriver.pkg`. Unfortunately, it may or may not install. Some people say it installs for them, but it doesn't install for me.

If it doesn't install, someone has created a script that can unpack the installer and get around the compatibility issues.

## 2. Legacy Java 6 with 32-bit support:

You need to install Apple's legacy Java 6 package with 32-bit support. Sierra isn't listed as supported, but it still works.

This legacy version of Java probably won't become the default if you have a new version installed, but that's fine, we will configure leJOS to use this version later.

(Incidentally, there were some plans to make it support 64-bit Java, but I wouldn't hold my breath.)

## 3. Download leJOS:

Download and extract leJOS for Mac as instructed here.

## 4. Setup environment:

You need to setup some environment variables as vaguely specified here. You will want to add something like the following to your `.bash_profile`, `.profile`, or other shell startup script, adjusting the `NXJ_HOME` to where you extracted leJOS.

```
# leJOS
export LEJOS_NXT_JAVA_HOME="/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home"
export NXJ_HOME="/Users/<USER>/<PATH_TO>/LeJOS/leJOS_NXJ_0.9.1beta-3"
export PATH="$PATH:$NXJ_HOME/bin"

```

(The `LEJOS_NXT_JAVA_HOME` variable is how you tell leJOS to use the legacy Java version.)

## 5. Profit:

Now when you open a new shell, the leJOS commands should work.

# Answer
> 2 votes
The one thing I needed to change to make the above solution work was this:

```
LEJOS_NXT_JAVA_HOME="/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home"

```

I hope this can be of help to someone.

Wim

---
Tags: nxt, lejos, mac
---


title: How to straighten 32L axles?

text:
# Question
Title: How to straighten 32L axles?
I have a number of the 32L technic axles, but most of them have some bend to them. Is there a straight-forward way to straighten these? Trying to bend them by hand has not seemed to change anything, and I'm afraid I'm going to snap them if I try harder.

# Answer
> 7 votes
I have had some success straightening bent train level crossing gate barriers by first immersing the pieces in a bowl of hot water\*, for around 5 minutes to soften the plastic and then immediately trapping them between two hardback books and applying weights until they have cooled.

So by using Joubarc's method to hold the axles straight combined with a pre-soak you may get better results.

*LEGO is plastic and plastic can melt, you only want to soften the plastic not melt it further out of shape. See this question for more.

# Answer
> 7 votes
I'd suggest storing them straightened up for a while, if possible in 32 adjoining 1x2 bricks with cross hole, and add a few layers of bricks to hold them in place. At least it's a pure LEGO solution, but I'm not sure how efficient.

# Answer
> 2 votes
I know that this is an old question, but I recently purchased a set with these in it, and they were bent like you describe when I took them out of the box.

Lego were kind enough to send me replacements for free.

# Answer
> 2 votes
I got one severely curved 32L axle which I straightened with hot water in a plastic tub.

Leaving the axle in water about 70-80°C for a few minutes managed to do most of the straightening job.

Try not going much above 80°C as otherwise you reach the temperature at which ABS will start to become rubbery (used in injection moulding). At about 95- 105°C your part’s shape will be ruined because of ‘melting’.

To further straighten the axle, I repeatedly put the axle in hot water for 2-3minutes, then slightly “over-bent” the axle (to overcompensate the remaining curvature), and then keeping the axle held this way under running cold water for half a minute. This way the axle becomes rigid again, in the desired shape.

On subsequent iterations I applied the same method very locally to cancel out remaining local curvature.

Eventually the axle can be straightened enough for it to do its intended job again. It took me no more than 20 minutes.

---
Tags: technic, repair
---


title: Can you identify this LEGO plane set?

text:
# Question
Title: Can you identify this LEGO plane set?
Sadly this LEGO plane crashed today. No one was injured, but I do not know where the instructions are, or the LEGO kit/product number. Can someone help me identify which kit it is so I can look up the instructions online?

# Answer
That's one of the alternate models for Ocean Explorer (31045):

The instructions are available on LEGO.com.
> 12 votes

---
Tags: set-identification, vehicle
---


title: Why are there scratches on new bricks?

text:
# Question
Title: Why are there scratches on new bricks?
When I assembled the new bought "Old Fishing Store, Item No: 21310-1" I noticed a very unusual imperfection of parts. On every one of the 43 tiles "1 x 8, reddish brown, Item No: 4162" I found scratches on both ends. Also the injection points I think are much more visible than normal. I contacted Lego and they sent me 43 new tiles. Great, but still the same mistake. I contacted them again and, Lego service being Lego service, again they sent me 43 new tiles. Great again, but still the same phenomena again. So I ended up with 86 additional bricks that I found not fitting to the Lego quality standards that I'm used to. There was also no explanation or comment from Lego service.

My question is what is causing this strange scratches? The appearance is not consistent. They are not straight and appear in different strength's and lengths.

# Answer
I have seen this happen with parts originating from older Lego part molds (dies) (like the 16L studded Technic beams in the 42009 Mk2 crane truck). My take is that the molds have been scratched during a maintenance operation but that the mold damage is still within tolerance for Lego.

Creating a new mold (die) is very expensive.
> 3 votes

---
Tags: piece-information, manufacturing
---


title: Bucket Wheel Excavator not powering up?

text:
# Question
Title: Bucket Wheel Excavator not powering up?
I just finished to assemble the Bucket Wheel Excavator (42055) set, I inserted new batteries in the battery box and tried to power it up.

The LED on the battery box blinks for a millisecond almost imperceptibly, and nothing happens.

I now wonder what could be the problem, I tried with several different batteries without luck, tried to clean the metal parts, but still nothing.

How can I understand if the problem is the battery box or the motor?

# Answer
**First: check battery condition.** Are all 6 batteries fully charged? Or for non-rechargeable batteries: are they all functioning (new, not expired, no chemical leaking damage)? If one single battery is dead or defective, it can prevent current to pass. If you have another set of fresh (or fully charged) batteries, try using these (but see also the step below).

**Second: verify proper battery placement.** The Lego battery box requires the batteries in each sub compartment to be oriented *the same way* (all tops pointing in the same direction \- no battery should have "inverted" orientation). Check that you placed the batteries in the battery box with the right orientation and with the proper polarity (as indicated in the battery box).

*As a side note - I always put a piece of plastic sheet ribbon (used in gift wrappings) in each side of the battery box compartment prior to adding batteries; this facilitates subsequent removal of depleted batteries. You can remove the last battery by pulling both ends of the ribbon.*

**Third: verify that the battery box works properly.** If batteries are healthy and battery polarity is correct, then first test the battery box *unattached*. The orange slider has 3 positions: on-off-on (either 'on' reverses the polarity for the motors attached). When the slider goes left or right (either 'on' position), the green indicator LED light should remain on. When the slide goes into the middle position (off), the LED indicator should remain off. If this fails, contact Lego to supply you a spare battery box.

**Fourth: verify that the motor works properly.** It is wise to test the battery box and motors prior to assembling any motorized model. If you know the motor previously worked, and you have access to another unused motor, test your battery box with that other motor. If the battery box doesn't manage to operate the motor, try using another battery box if you have one at hand. If that other battery box works, then contact Lego to supply you a spare battery box.

If neither battery box operates the unloaded motor, then contact Lego to supply you a spare motor.
> 2 votes

# Answer
As Phil B suggests you really must start by testing a motor by itself from the battery box. This will confirm whether that battery box is working or not.

My experience in Radio Control has taught me to test each "electrical" bit one at a time and in a logical sequence starting from the power source until the fault is identified.

For the future it worth testing electrical things like the motor and battery box **before** they get "built in" to a complex model.
> 2 votes

# Answer
Do you have another battery box from another set you could try? You could purchase the motorization set to have a spare battery box and some other useful components. However, I think I own at least 50 battery boxes, I have never experienced any issue with them. Likewise, I never have experienced any issue with motors that are new. What also could be the issue is that you have made a mistake in a building step somewhere which causes the drivetrain to block. The motors and battery box have circuitry in them so they shut themselves off if too much current is drawn, which happens when motors are blocked. I would test this with all switches in neutral and then see if the motor spins freely. If this is the case you'll have to test every function, see what blocks where and resolve it with the aid of the building instructions.
> 1 votes

---
Tags: technic, power-functions, electronics
---


# Question
Title: Please identify if these pieces are part of a set, medium grey and red Technic bricks with a window
I have these pieces, constructed a shown, that were given to me in a pile. Is this part of a set or something someone just build?

# Answer
> 7 votes
At first glance it looks like something out of Model Team set, like one of the trailers.

There are two types of standard Technic pins, black friction pins and grey frictionless pins.

Black friction pins are used to build strong connections and grey frictionless pins have low friction and allow parts to spin easily.

It seems odd that the two pins connecting the Technic bricks as shown below use grey frictionless pins as I have never seen an official LEGO set that wouldn't use black friction pins for this case.

The window also stands out as an odd feature in this build.

# Answer
> 3 votes
This is a real tough one.. I personally wasn't able to find a set that includes all the pieces in the pictures you included, but I found one that comes pretty close. My guess is that it is a late 80s or early 90s technic set.

What I found which has most of the parts, save for the window element in the middle of your pictures and maybe a couple of the red elements is set 8064-1.

I mainly based my search off the set having at least:

4x red tech brick 1 x 6

2x LG tech brick 1 x 16

2x LG tech brick 1 x 12

and some assorted technic elements like axles and bushings as well as some other red elements.

Hope this aids you in your search!

# Answer
> 1 votes
This is certainly a remainder of a "moc"

With the introduction of Technic in 1977 only the gray friction-less pins existed, so these where used in all Technic constructions by Lego.

Black friction pins are introduced is 1982 (look carefully at the set pictures in the following links: 1981 & 1982). This resulted that from 1982 on the gray pins where only used in parts that needs movement.

So the double gray pin usage in the photo, if original by Lego must be from 1981 or earlier.

The second clue found is the Light Gray 1x16 technic beam. This part is introduced in 8851-1: Excavator, which is a set from 1984.

**Conclusion**: No official set by Lego

# Answer
> 0 votes
I can't remember a Technic set with a small Lego Classic window, so to me it looks like a creative mind at work.

In early days there were no black friction pins. Studded beams in red and gray remind me of a caterpillar backhoe or bulldozer set from the 1st half of the 1980s. The toothed half width bush also places the parts halfway the 1980s.

---
Tags: set-identification
---


# Question
Title: Help in identifying elements used on LEGO Batman movie's Daleks
I've been working on making a replica of the Dalek from LEGO Batman.

I've worked my way through this video tutorial and the author identifies some differences between their (awesome) effort and the original from the film.

I've built a replica in the LDD and was trying to identify how the laser was constructed.

Currently the author is using a 64567 "Light sword shaft" and 30374 Light sword blade, something like this...

This is okay, but lacks some of the articulation which it should be capable of. Now, I appreciate that the movie was CG based and some "cheating" probably took place, but I'd like to get as close as I can

From the movie...

I've identified that the business end of the barrel is (indeed) a 64567 "Light sword shaft", but I can't identify the shaft element which it is attached to (highlighted).

The 64567 part needs to attached to a 3.2 shaft part, but I can't identify the part which seems to have been used, any help would be greatly appreciated.

I've spend some time going through the LDD catalog and brickset trying to identify it, without luck.

It "could" be 32828: Plate 1x1 Round W/ Horizontal 3.2 Shaft, but it doesn't seem to have the same reduction or node at the end. I've tried using a 92690 "0.2 Shaft w/ cored knob" along with a 87994 "Shaft 3M 3.2" to join the 64567 together, but it doesn't generate the same shape (and is generally to long)

# Answer
> 12 votes
It looks like Minifig, Utensil Tool Box Wrench - 3-Rib Handle Item No: 11402i (although it looks like the ribbing may have been omitted in the CGI model):

The socket end can clutch a stud, so it can be attached there.

This newer variant of this piece has come in flat silver, which is probably the closest color so far if not *the* color, in 5 different sets so far.

---
Tags: part-identification, moc
---


# Question
Title: Is it possible to determine the approximate age of these bricks only by seeing their injection points?
Is it possible to determine the approximate age of these bricks only by seeing their injection points?

# Answer
I cannot tell by the injection markings but having been a lego collector since 1967 I can tell that they are around that era. They look like some of the original ABS plastic. I also have some even older lego bricks in my collection (circa 1960) and they are of a different plastic but you cannot see the molding points on those.
> 4 votes

---
Tags: piece-information, vintage
---


# Question
Title: What's the fastest way to rebuild different sets that have been brought together
My mom did something to my LEGO. When I was a kid I loved playing with them. Frankly I have no interest in it anymore. She broke down all them sets, and put them all in a huge box.

I still can figure out some parts, but I don't know if it's better to break down every piece and rebuild from scratch. I'm not talking about 3 or 4 sets, more like 20 to 30 LEGO sets worth around 3k to 4k euro... I want to resell it, sadly she took away the building books and the boxes and did them away too.

# Answer
> 4 votes
In order to gain value out of this, you're going to have to put some work in.

Start with the largest sized kit that you remember doing and assemble the parts (find the building instructions online). Then move onto the next smallest, and so on.

Obviously, you're not going to remember the details of all the kits you had, but the largest ones should be more memorable (and usually they're worth more).

# Answer
> 1 votes
Without the instructions it's going to be hard to reconstruct the sets and it will reduce the price anyway (I think people who cares for old sets also want the instructions). But you can find many instructions online.

Your valuation of 100-200€/set is probably unrealistic. There are lots of sets in that price range, but they are fairly large (especially in the upper end), so it doesn't sound like a typical kid collection, and when you include that it's used without boxes or instructions it becomes even more unrealistic.

I would need to see the parts to give a real recommendation, if it's all (but it has to be quite close) bigger parts that are reasonably easy to connect I would try that, but you easily end up spending more time looking at the model to find out where some small piece goes.

---
Tags: building, star-wars, disassembly
---


# Question
Title: How often does LEGO make colour substitutions?
I'm currently building the UCS Millennium Falcon and ran into a step where the instructions say to use two different shades of grey in the greebling, but the bags for that step only contain one single shade (but the right quantity).

This seems odd for such a prestige level release, so my question is whether this is "normal" or whether I should be asking for replacement parts.

To clarify - step 12, the round vents at the top back of the Falcon should contain black 1x2 grills, and dark gray 1x2 grills are used elsewhere on the paneling for detail. The bags for this step contained no black grills - just the dark gray. Proper quantity, just wrong colour.

This isn't a case of the constructor misusing one part accidentally in place of another - the step is built with no missing parts, only a few random spares, it just has the wrong colour grills in the vents.

# Answer
> 8 votes
In my experience, this typically means you used the other colored part by accident somewhere else in the model, for example in a place where it is used on its own, and it was difficult to determine the exact color of the piece at that time. This happens a lot with colors like dark bluish gray, light bluish gray and pearl gray. You will need to go back through the manual to find previous places where this piece was used and confirm you used the right color.

# Answer
> 3 votes
It might help to compare what you have with photos online of the same portion of the model.

In my experience, I sometimes find the right part in a later bag, or left over from a previous bag.

While I was building my USC Falcon, I just maintained a pot of "extras" and dipped into them whenever I couldn't find a particular part.

There's an awful lot of small parts in this model, and it's easy to skip or add too much greebling.

---
Tags: colour, replacement-parts
---


title: Determine assembly steps from LXF file

text:
# Question
Title: Determine assembly steps from LXF file
I’d like to build a MOC of a Technic vehicle that was posted online using the provided LXF file of the completed model.

I was able to open the LXF file with both Bricksmith and Stud.io, but, as far as I can tell, it is not broken down into a sequence of assembly steps. In other words, both programs shows *just* the completed model.

I’d like to know either: (A) how to view the intended/embedded step-by-step instructions, assuming they exist, and/or (B) if there is a common/best practice for manually determining an assembly order when all you have is a completed model in an LXF file.

FYI, the model I want to build is the awesome looking Chili Crawler by PunkTacoNYC. It can be seen on YouTube, and the LXF file is available here.

# Answer
The LXF file contains the complete model as created with Lego Digital Designer (the Lego CAD tool from The Lego Company). The model usually doesn't require to have building steps as they are (always) automatically generated from the model.

For normal, non-Technic models, Lego Digital Designer (LDD) is able to create automated building instrutions. My experience with LDD and Technic models / MOCs is that you have good support for designing the completed model, but that for the generation of building instructions you're better off with other tools.

You can translate an existing LXF file into an LDraw model (file extension: .ldr), but for some exotic (read: Technic) parts, the translation of LDD parts and LDraw parts is either incomplete or has problems with part orientation. This means that you may have to do manual edits to your model in order to have an (almost) complete translation into LDraw file format. See e.g. this site for details.

One advantage of the LDraw format, is that you can define "building steps" and sub assemblies in the design, which makes the generation of complex building instructions easier.

A tool for creating building instructions from a LDraw model, is LPub3D. Otherwise I'd suggest using a Lego CAD tool such as LDCad.
> 2 votes

# Answer
Starting from LDD files and LXF, a good software is Blueprint from msx80

https://www.eurobricks.com/forum/index.php?/forums/topic/108346-software-blueprint-a-building-instruction-generator-for-ldd/

With this, you can organise how you want the pieces to get assembled (by default the auto-generated steps are not always optimal), then export a PDF, I think it's pretty great.
> 2 votes

# Answer
You can use LDD (Lego Digital Designer) the official LXF viewer by Lego. This allows you to create building instructions to view or export to html.

You can also use this software to build models, and i find it much better than other softwares since it is simple, with easy UI.
> 1 votes

---
Tags: instructions, ldd, ldraw
---


title: The four armed minifig

text:
# Question
Title: The four armed minifig
How do you put together a four armed minifig?????

I really want one.

# Answer
> 4 votes
The good news is: This Minifig is still available (as of March 2017)! The bad news is, he's only in two sets and they're both quite expensive. He's Nadakhan, the captain of the Sky Pirates in the Ninjago range. There is also General Kozu, but his set is even more expensive.

As Kevin points out in the comments, Lord Garmadon appears three times in the LEGO Ninjago Minifigures series (Garmadon, Volcano Garmadon (pyjamas), and Flashback Garmadon (suit and tie)), so it's possible the part is now more widely available.

The key part from Nadakhan's body you need is:

> Torso, Modified Short with Armour Breastplate...

Or there are some other options from earlier Ninjago sets available as well.

Which accepts a standard neck post and has holes for the arms.

# Answer
> 2 votes
Also there is Z-95 Headhunter (75004) which has General Pong Krell, but it is also fairly expensive.

---
Tags: minifigures, shopping, minifigure-identification
---


# Question
Title: How To Plug Detected Light Values into Variables and Still be Usable in Programs in EV3-G
I've seen teams, mostly in the world festival do this, and what they do is they program the robot so that when a brick button is pressed, the robot detects a value (usually RLI) and it is used later in the program. My program looks something like this so far.

Am I on the right track? Is this program correct? Or am I completely wrong?

The program runs OK, but the variable can't be used later in the program.

# Answer
> 2 votes
First guess: the wait for button command is bad practice. Well, not the whole thing, just the use of the middle button. The reason is that that button is also used to start the program. The program may be jumping past the wait for and saving to "Midpoint" before humans notice that the program has started. Try any other brick button.

# Answer
> 2 votes
Your example doesn't read a RLI value. It reads and stores a color index value (0 through 8). This wouldn't stop you using the variable, but the value may not be what you expect.

Variables are global. You can read or write them anywhere in your program. The value of the variable is the last value written. Variables are not persistant. When your program ends the variable goes away. This means you cannot use variables to set a value and use it in a different program. To do something like that use a file,

---
Tags: ev3, programming, colour, sensor
---


title: Connecting "out of system" roads?

text:
# Question
Title: Connecting "out of system" roads?
I've been trying to figure out how to connect SNOT road models that are at varying angles to one another. You can see my efforts in this thread.

Are there any interesting methods of connecting roads like these that most people might not be aware of? I read up on integer triangles, but there are none for 45 degree angles, and probably none for 30 and 60 degree angles as well.

Are there any special parts that make this possible?

See also: https://math.stackexchange.com/questions/2607147/is-there-a-pythagorean-triple-whose-angles-are-90-45-and-45-degrees

Here is an example that is fairly close, except that the road pieces are not connected to one another.

# Answer
There ARE integer sided triangles that have angles of 60 or 120 degrees, see here : https://en.wikipedia.org/wiki/Eisenstein\_triple but I'm not sure how this helps you for building roads. 45 degrees there indeed aren't any. A progress of going one stud forward one stud left will get you 45 degrees if working studs on top. In case of SNOT 2 studs forward, 5 plates will also progress in an angle of 45 degrees. There are elements that let you progress half a plate, so 1 stud to 2.5 plates works also. For 60 or 30 degrees, the tangent is irrational so no 'precise' or exact progression exists, but it can probably fairly well be approximated. There are technic pieces called angular connectors that make angles that are multiples of 22.5 degrees. Also several connectors that make multiples of 60 degrees. Also hinges that "click" in angles of 22.5 degrees...

Update: picture of angular connectors

you would additionally need technic axles and bricks having axle holes:   But there are lots of other ways to connect the connectors, e.g. bricks with pin holes and a half-axle pin, half pins with stud, axles with stud,...
> 3 votes

---
Tags: building, snot
---


# Question
Title: Which set did this Technic assembly come from?
*I posted a week or so ago and had great success identifying a LEGO Star Wars set which is now completed. So.. thought is would try again.* Can anyone help me identify what this could be?

# Answer
> 7 votes
According to BrickLink there are only 4 sets with the arched element in it in Dark Bluish Gray. From those only 8435 Technic 4WD seems to fit:

---
Tags: set-identification
---


title: Obtaining LEGO blocks

text:
# Question
Title: Obtaining LEGO blocks
In the olden days, it was possible to go to the hobby store and get a box of specific capability. Now adays, I basically see lego blocks sold as part of "action" sets.

Question: Is it still possible to get blocks of a specific type in a specific quantity?

# Answer
There are a few things I can think of.

## 1. Bricklink

Bricklink is a reputable online site. You can buy any pieces ever made by LEGO across the globe. Their site may seem hard to navigate at first, but it doesn't take much to get used to. Also, if you have any questions you can ask here.

## 2. Pick a Brick

If you live near a LEGO store you can find yourself a variety of parts. The prices are decent. Don't be afraid to fill the cup a little more than full. They have tape just for that purpose. The selection changes as they run out of parts.

## 3. Local LEGO Shops

There may be a small locally owned LEGO establishment near you. I am not talking about a supermarket like Target or Walmart. I refer to small "holes in the wall" that may have a pick a brick much like LEGO Stores.

## 4. Bricks and Pieces

This is a suggestion that I myself have not used personally. Apparently you can order any parts they allow in production in your desired quantity. I am not sure of the price, but the reliability should be there since it is from LEGO.
> 2 votes

# Answer
Look under the "shopping" tag in this forum. You will find answers about various aspects of acquiring LEGO.
> 2 votes

---
Tags: piece-information, shopping
---


# Question
Title: How do you make a triggered counted ball drop?
Is there any solution on making a drop of a counted number of balls when one ball passes through the system?

For example: One ball falls into a hole on the top and ten balls (plus/minus (not important) the ball that fell in) come out.

I have thought about letting one ball drop into the system and activating a lever which pushes open a tunnel with a lot of balls in it and the lever then self-closing afterwards. To limit the number of balls dropped there should be a closing mechanism on the upper side of said tunnel that closes when the tunnel itself opens, so only the balls in that section would get dropped...

But how would you do that without jamming?

If someone cares about the ball-size and weight, that should not really matter because the basic construction can always be a little bit reconfigured if the ball size is between 12 and 15 mm. Same for the weight.

EDIT: There has been some misunderstanding apparently, I am sorry for that. It should be noted that this mechanism should be repeatable for as long as you have a supply of balls coming in from a second source (auto-refilling of the reservoir). While this itself is not an issue because you can simply make a big pressure-based ball reservoir that gets triggered everytime the small reservoir empties, it is an important aspect because it means the whole mechanism should not only be able to run one time.

# Answer
> 6 votes
I've seen this done in a GBC module that counts the balls that pass by. It worked with scales that eventually tipped over, each scale representing a decimal of the total number of balls that passed by.

Can't exactly find the GBC module but found this clock from jkbrickworks that uses the same principle.

# Answer
> 2 votes
I don't know if this is practical, and I can't test it as I don't have enough compatible balls to build GBC type mechanisms, but what comes to mind is:

1. Have the balls run down a trough.
2. The trough ends in a segment of trough which is 10 balls long and pivoted about the long axis.
3. The triggering ball causes the trough to spin about that axis, dumping the balls sideways into a receptacle.
4. The top end of the moving trough is designed so that it is flat and blocks further balls from sliding down (without jamming) until it returns. This is the critical area to prevent it from jamming.

For ease of operation, the trough's weight should be balanced about the axis. The weight of the balls should assist in the dumping movement — either not enough to start it, or the trigger mechanism prevents movement until triggered.

---
Tags: technic, mechanical, gbc, balls
---


# Question
Title: Is it legal to sell a custom element that provides a Technic pin connection?
I'm wondering if it would be legal to produce a custom piece for Lego Technic and sell it? The piece features 4 compatible connection holes for Technic pins. From what I've researched in the Lego Technic patents, the claim (in the first sentence of each patent) applies to "sets" not individual parts. Here are the patents:

Does anyone know if there are specific patents covering the pin hole system?

Note: I would of course make sure to use my own designs and not copyright infringe on any of their trademarks regarding packaging, marketing etc.

# Answer
> 6 votes
I am not a lawyer, and I recommend you consult one before you start dropping money on injection molds, but as far as I know this should be fine. SBrick definitely already does this:

In most jurisdictions, patents have a term of 20 years or less. The Technic pin connection dates back to Expert Builder in 1977, so it is not patent encumbered at this point.

The two patents that you linked to from the late 1990s appear to be for ZNAP, which uses a different connection system:

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# Question
Title: Is there a listing of the Types of LEGO blocks?
What are the different specific "types" of LEGO blocks that have been manufactured? I am not talking about any of the action figures or themes. Is there some type of list, as to type, size, colors?

Are they still available for purchase?

I was especially interested in the following that I have not seen in awhile.

1. Cylinder (1x1)
2. Beveled (various)
3. Lettered (1x1 per letter)
4. Clear Window blocks (in 1,2,4,8 stud sizes)
5. Plates
6. Blocks with a hole of a wheel and of course the wheel.
7. Partial-circle/curved parts

# Answer
There are lots of sites that document all the LEGO bricks, and indeed other items they make.

Two oft-cited examples are:
> 5 votes

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