A more advanced form of LEGO®, allowing for the creation of more realistic working parts.

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3
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1answer
78 views

How do I diagnose a problem with electronic bricks and motors?

My children and I recently assembled the 42030 RC VOLVO L350F Wheel Loader (aside: with the 1,600 pieces and time investment, this set will likely survive to the heat death of the universe intact ...
5
votes
2answers
319 views

Can you identify this yellow crane?

Can you identify this one? It's part of a series of models I had as a kid that I want to take apart for my own kids now, and I'm looking for the original instructions.
4
votes
1answer
187 views

Can you identify this model of a yellow truck?

It's part of a series of models I had as a kid that I want to take apart for my own kids now, and I'm looking for the original instructions. Can you identify this one?
5
votes
1answer
68 views

How much current do the LEGO motors draw?

I'm building a project with Raspberry Pi and some other electronics driving the LEGO Power Functions M-Motor (8883) and I need to know how much current those motors draw under load. Has anyone done ...
6
votes
1answer
2k views

Virtual LEGO / Technics / Mindstorms simulation environments

I know that there are quite a few LEGO CADs floating around, but are there any physically correct simulation environments for models built with LEGO / Technic / Mindstorms parts, that would, for ...
3
votes
1answer
69 views

Instruction for installing rc to LEGO unimog

I'm searching for an instruction to install a remote control to my LEGO unimog. There are a log of youtube videos showing completed unimogs but I can't find any instruction.
2
votes
1answer
94 views

How much tension can I expect to get out of a lego chain before it starts to give away?

Assuming I am using the technic chain links to make a chain, how much force can I expect to be able to get out of the chain before it breaks? Suppose I am using a 16t gear to directly drive a 24t ...
2
votes
1answer
414 views

EV3 Error and VM Program Instruction Break

I'm making a program which is very complex and large but it does not contain any Arrays in it. Weird thing is, last night it worked fine but today when I downloaded the exactly same thing into the EV3 ...
5
votes
4answers
236 views

How to help a yellowed brick with a sticker?

My parents recently finally decided they can return me my childhood toys with 1990s Technic sets including the 8880 Super Car. All other sets were in boxes, but this one spent the last 15+ years ...
3
votes
3answers
215 views

Where can I get threads compatible with LEGO pulleys?

Have LEGO threads ever been produced? Even the biggest LEGO rubber band is too short to meet my requirements. I need them for this year's WRO challenge. Note that the challenge only allows Lego ...
26
votes
6answers
9k views

What are the best options for building a LEGO RC car?

I would like to build a remote controlled car. And if someone already has a good solution for that I would be glad to try it. It's been a while since I had the time and material to build some LEGO ...
4
votes
1answer
309 views

What is wrong with a Lego pneumatics system that won't go?

I own a LEGO Technic Unimog U-400 (part number 8110) and have been very pleased so far with the performance of its pneumatic system. However, after storing for just a month or two (after a good 5+ ...
1
vote
0answers
56 views

What are the measurements of the different Lego instruction booklets?

I've noticed that there are at least three different sizes (eg 7.8"x5", 4"x5.8" and 7"x8"). Are there other sizes?
3
votes
2answers
221 views

Custom Power Functions plug design

I'm considering the possibility of making my own Power Functions-compatible sockets for a project. I'm designing a module board for a single-board-computer with motor drivers and would like to encase ...
3
votes
1answer
98 views

Wiring and Controlling an 88004 servo from a RaspberryPI

My 88004 servo does not move at all. Don't know how I should connect the wires correctly. I think the inner two cables are C1 and C2 and the outer two GND and VCC. When I connect 6.5V to the outer ...
5
votes
1answer
577 views

How to control a 88004 Servo Motor with a Raspberry Pi?

I am able to control a simple servo motor such as SG90 by using pulse-width modulation. However when it comes to controlling a 88004 LEGO Servo Motor it is simply a nightmare. By using PWM all I ...
2
votes
1answer
147 views

Differences between EV3 Gyro and Hitechnic Gyro

I understand that the Hitechnic Gyro was made for NXT but are there any advantages of using it over the normal lego gyro in EV3??
12
votes
4answers
1k views

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 ...
5
votes
1answer
86 views

Difference between gyro sensor and compass sensor

Does the HiTechnic compass perform the same function as the gyro sensor? I have been trying to find out the difference.
1
vote
0answers
37 views

How do you display EV3-G images properly on an NXT screen? [closed]

When I use the EV3 programming software to put an image on the screen of an nxt, it cuts off 3/4 of the image. How can I stop this from happening?
2
votes
1answer
110 views

I need help Identifing this set by the picture

I have a blurry picture of a set I found at a LEGO fair, and I would like to know what it is: Thank you.
3
votes
1answer
154 views

Overview of Engineering Principles incorporated in Technic LEGO sets

I run an after-school technology education program and want to expose kids to real-life engineering by means of having them build commercially available Technic kits which we then deconstruct and ...
1
vote
1answer
268 views

Linear Actuator of the boom of 42006 jams

I just built a 42006 excavator, and the Linear Actuator jams such that it can't be rotated. I think that the overly sharp angle of the u-joint at the top of the boom is the reason. Is there a ...
2
votes
1answer
170 views

Can you use a beveled gear as a pinion?

I would like to use the PF servo motor for steering, however it is very large - I was playing with the idea of having it mounted vertically, and then using bevel gears to change the direction of the ...
4
votes
1answer
125 views

Any issues with this non-standard gear combination of 12t gears?

I don't see any "accepted" gear ratios for a stud-less direct-diagonal gear combination on sariel's excellent gear coupler but by shifting 12t gears such that they mesh off-center, it seems to work ...
3
votes
2answers
139 views

At what voltage do the c1 and c2 lines run at when controlling a lego servo motor?

related: how to control a servo motor from a raspberry pi The raspberry Pi normally outputs 3.3 V signals from it's pins, however there are logic level converters for interfacing with higher-voltage ...
3
votes
1answer
188 views

What Technic vehicle is this in black and red?

Any help with the set this piece is associated with, would be appreciated.
3
votes
1answer
138 views

Why can't I combine a EV3 Motor with a Technic frame in LDD?

It is easy and stress-free to attach a frame to a large motor in a vertical or horizontal manner as shown in the picture in real life. But I can't do the vertical version inside LDD. Anyone knows why? ...
3
votes
0answers
166 views

8258 Headlight assemblies

Anyone else having a problem with with headlight assemblies on 8258 crane truck? I can't seem to fit them in due to interference from fog light bar. Thanks
3
votes
1answer
166 views

How exactly does the pull-back motor (12787) work?

I've got the 42034 Quad for my birthday and it's been really fun to play with technic after so many years. I am very curious about one thing, though - how does the pull-back motor (12787) work and ...
4
votes
1answer
182 views

Which combination has a lower gear friction?

I need roughly a 1:3 reduction and I see a couple of ways to achieve it: using a 8t gear and a 24t gear (1:3) using 2x 12t gears and 2x 20t gears (1:2.779) using a 16t gear and a 40t gear (1:2.5) ...
4
votes
1answer
483 views

Pre-Technic gears?

I have this set of LEGO gears. I remember seeing them first at my grandparents in the mid 80's. They predate my first Technic sets (~84 or 85). I have fond memories of my dad building a 3-speed ...
5
votes
1answer
361 views

What is the “Module” of a LEGO gear?

Module, m this indicates the tooth size and is the number of mm of pitch circle diameter (p.c.d.) per tooth. For gears to mesh, their modules must be equal. Gear ISO standards and design ...
3
votes
2answers
265 views

How important is a center differential on a 4WD model?

I am looking to make a 4WD, single-engine powered vehicle, and I have seen others such as this which use three differentials to distribute the power to all 4 wheels: ...
6
votes
1answer
441 views

How should I connect two LEGO cylinders with pistons to measure the movement caused by sea waves?

As part of a school project I need to make a model of a snake electricity generator. I would like to build this with LEGO elements, and for that, I need to measure the movements of the cylinders ...
3
votes
1answer
111 views

Best system for lifting things without pistons

So I am Building a Big walker thing with a mining laser on bottom that can be lifted on one half and the other attached to the vehicle but I cant seem to find a way because the hooks attached to the ...
2
votes
2answers
243 views

How to design ackermann steering with lego wheel bearing front?

I wanted to use a steering system based on the 11949 part: But I am not sure how to use it in an ackermann system - I would like to be able to have drive and suspension on the wheel, and this piece ...
11
votes
3answers
879 views

What tool can get the Technic pin out from a connection closed in the other end?

I'm having trouble removing these LEGO Technic pins apart from their connectors and I don't want to use carpenter tools like pliers which may damage the bricks. What tool can get the pieces ...
3
votes
2answers
168 views

What is the difference between these two Technic half bushings?

While randomly browsing some LEGO sites, I came across a weird (to me anyway) looking bushing. Its part 4265c. Below is one of the images describing it and the left one I recognize, but the right one ...
4
votes
2answers
180 views

Large trap door - alternative to door with frame 4595708

I need to build a large trap door, the trap door 4x5 with frame 6x8 is too small for my model. Other doors/hinges seem to have too much resistance and the door doesn't fall by itself, it must be ...
1
vote
1answer
172 views

Can Mindstorms EV3 communicate using protocol 802.15.4?

My aim is to make the robot communicate using protocol 802.15.4 through a USB dongle 802.15.4 over 6LoWPAN. The robot has to be able to get information from TelosB. I wonder whether this possibility ...
3
votes
1answer
223 views

How much torque can a lego axle handle?

from to this question, it seems that the gears are stronger than the axles, which begs the question of how strong are the axles? if you connect one of the stronger motors, such as say the buggy motor: ...
5
votes
1answer
734 views

How to build a limited slip differential?

Lego provides a couple of ways for building a differential, such as this: and also provides a limited-slip gear like this: ...
4
votes
2answers
452 views

How can I attach a Technic Linear Actuator to a EV3 Medium Motor?

I'm pretty new to serious LEGO building (never got past very blocky houses as a kid but got into Technic a couple of months ago) and need to connect a Technic large linear actuator (61927) to a ...
12
votes
6answers
8k views

What are the largest Technic-compatible tires on the market?

I am looking for the largest LEGO wheels with tires available to build a nice-sized RC LEGO car. Of course I will start with the simplest prototype, but I would like to achieve a design which will ...
4
votes
4answers
1k views

What other uses are there for pull-back motors?

Sets 42010 and 42011 feature a pull-back motor. They have a very high torque for a very small numbers of turns, they then free-wheel. I'm trying to find alternate usage for them. That is anything but ...
11
votes
3answers
4k views

How to start with technic?

I have bought myself the technic set 9393 Tractor. I really like the model and I want to dig deeper into the Lego technic universe. I am not focused in building pre-designed models (although I enjoy ...
0
votes
1answer
117 views

9398 problem with the front wheels

I've just finished 9398 4x4 Crawler. The rear motor works properly, but the front motor doesn't: The wheels seem to be locked, although they spin freely when I turn them by hand. What could be the ...
5
votes
1answer
389 views

How can a Mindstorms robot lift something very heavy?

I have a small LEGO Mindstorms robot and I have to lift something heavy. Now it seems not possible because the motor is not heavy enough.
18
votes
4answers
4k views

When did Lego decide that it was okay to put a stud into a technic hole?

At one point, Lego didn't really support putting a stud into a Technic hole, stating that it caused too much stress on the bricks. And for a while, there were no sets where that's the case. However, ...