3
votes
2answers
59 views

Gearing down a PF XL

I'm looking for the best way to gear down a Power Function XL. I need to achieve a very slow output RPM (less than 1-2 RPM). I've tried a 625:1 gear (trough 40:8 gear). Can someone link to a well ...
2
votes
1answer
55 views

Lego EV3 doesn't respond to direct command

I tried to execute command (via bt) play tone: play_tone = '\x0F\x00\x00\x00\x80\x00\x00\x94\x01\x81\x02\x82\xE8\x03\x82\xE8\x03' # send commands to EV3 via bluetooth with ...
8
votes
4answers
7k views

Are there any lego base plates that are compatible with duplo?

I'm thinking of making a lego table but my 2 children both use different lego. My oldest uses normal lego and my youngest uses duplo. Just wondering if there is a base plate that both types of lego ...
3
votes
1answer
62 views

How can I tell if my NXT motor is faulty?

I pulled my old Mindstorms NXT out of storage (it's been there for a few years). After patching together a test robot, I noticed that my motors behave strangely. At first, one of the motors did not ...
5
votes
2answers
280 views

Any way to create a gear+chain, like for a bike?

I would like to create a LEGO bike. I can imagine how most of it would work, but i'm stuck at the chain. I need a way for the turning pedals (at one spot) to cause the wheel (in the back) to spin ...
19
votes
4answers
2k views

Is there a logic to the way The LEGO Group fills the plastic bags?

When opening a new box, most of the pieces are in closed plastic bags, and sometimes inside those plastic bags is another plastic bag for smaller pieces. I find the pieces, for the most part, rather ...
6
votes
1answer
105 views

Preparations for outside display

I am thinking of using LEGO to make some outside yard art, (large minifig scale castle) and wondered what I should do to prepare them for being outside in variable weather conditions (in the Seattle ...
6
votes
2answers
124 views

Fixing poorly applied stickers

Does anyone have any tricks to removing a sticker and reapplying, after a significant period of time? I recently purchased a lot of sets from 2000-2010 range, and the stickers look like they were ...
15
votes
4answers
5k views

Are all the Magnet minifigs now glued on and how should I remove them?

A couple of years ago (around 2010 I think), I bought a number of the Star Wars magnet sets, as they looked like a (slightly) economical way of buying a number of specialist characters (including the ...
4
votes
1answer
65 views

What are the curve radii for the curved slope pieces?

Does anyone have a table with the curve radii for the curved slope pieces? If not, does anyone have a good idea for measuring a third point on the curve? Since I know the front and the back ...
8
votes
4answers
8k views

What are some examples of advanced train layouts possible with the PF train sets?

I recently got my first train set, the Constitution Chase, and it has sparked my imagination for building train layouts. My 3-year-old son has a small collection of wooden trains and we enjoy building ...
2
votes
1answer
224 views

How to locate objects, and move towards them, without pre-programming the path

So I need to find objects in an enclosed area, I have access to the standard set of NXT sensors, i.e. ultrasonic/light. However, the ultrasonic sensors seem to be very unreliable and erratic, in ...
3
votes
2answers
173 views

What are the largest LEGO® Power train sets available commercially?

What set(s) are the largest by number of pieces? These sets could be retired or existing. I am also curious what set(s) have the most rails pieces included.
8
votes
3answers
2k 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 ...
7
votes
3answers
1k views

How to Make a Lego Claw Arm?

I am trying to build a lego claw arm to pick up stuff that is out of my reach and I need some ideas on how to design it. I would like a mechanism to be able to open and close the claw from the ...
2
votes
1answer
216 views

What's the sight of the ultrasonic sensor according to the distance of the object?

Hey I'm programming a sumobot for a first-year university Civil Engineering project. We should need the sight of the ultrasonic sensor according tot the distance of an object. For example, the sensor ...
7
votes
1answer
477 views

Emmet's couch model in official sets different than the movie?

Lego's official building instructions for The Sea Cow set include building instructions for building Emmet's couch from The Lego Movie. Are there differences between this model and the one actually ...
2
votes
1answer
85 views

How make robot turning going straight?

I have been struggling with this function for a while. I want my robot to turn left until it detects black then turn right until it hits black again. Then, I will divide the angle in half and call ...
2
votes
1answer
112 views

Is the LEGO Mindstorms EV3 brick waterproof?

I am trying to build a ROV (Remotely operated underwater vehicle) with Lego Mindstorms Ev3. Is it waterproof?
3
votes
2answers
120 views

Strain Gauge on Lego Bridge

I had an idea to teach my son (almost 4) about bridges and large structures from an engineering point of view. I thought that it would be cool to build a large bridge and put a strain gauge on it. One ...
3
votes
2answers
241 views

IDE recommendations for EV3 programming

Does anybody have any recommendations for non-GUI programming of the EV3 unit? I'm impressed by the LabVIEW software, but as a professional C# and VB.Net programmer (with C, C++ experience), I find ...
2
votes
1answer
229 views

can't send multiple commands to EV3 using Python

I want to use Python to send commands to an EV3 brick. In C++ things work as expected - for instance, this starts the motor on port A and then stops it after a while: #include <unistd.h> ...
0
votes
1answer
61 views

where can I find simple Lego ideas [closed]

I have just acquired a bunch of bricks and specialized bricks. Where could I get a lot of ideas? Anything to do with a city would be good. I have already tried the LEGO club.
1
vote
1answer
113 views

What is the input to the Speed Regulator?

I wanted to buy a transformer for the speed regulator, so based on this image, I bought a transformer with 12V DC output. It works. However, discussing this with a fellow AFOL, he pointed out that ...
1
vote
1answer
35 views

NXT shuts down USB on Mac after connecting motors

After successfully connecting our NXT to my Macbook Air and upgrading firmware to 1.31 we built our first robot. We plugged in the motors to ports A, B & C and now we get an Error stating that USB ...
9
votes
2answers
593 views

Is it possible to add the power functions to Western Train Chase?

I recently got the Red Cargo Train and it's a great Lego set but a Cars themed train going around my Christmas tree would be even better. Has anyone gotten the power functions to work on the Western ...
2
votes
2answers
1k views

Is there a fix for an NXT reporting “File error!” when running an EV3 program?

I downloaded the new EV3 software from Lego and installed it on Windows 7. The EV3 software runs. I plugged in an NXT using a USB cable. EV3 can edit the memory on the NXT and remove ...
1
vote
2answers
173 views

How to install NXT Firmware 1.28?

Lego is giving 1.31 from their website but I need 1.28, how can I install it?
9
votes
3answers
170 views

Brick-built alternative to “Door 2 x 5 x 5 Swivel, Bracket Base”

I am trying to make a brick-built alternative to the swivelling door piece that's frequently used to provide secret entrances in castle sets. Example: this combination (images from Bricklink) The ...
9
votes
3answers
868 views

How many spaceman minifigure variations exist?

I was looking at collecting all the different Spaceman minifigures. So I'm wondering how many different types(styles) of Spaceman do exist. Color variations is not necessarily but it would also be ...
4
votes
1answer
621 views

Where to find older sets (eg. Classic Space)?

Can people share their experiences on how they locate older sets? Have you had luck with flea markets, garage sales, thrift stores, etc.? Or is everything done through eBay and BrickLink? Any comments ...
1
vote
1answer
61 views

Is it possible to use a LEGO NXT ultrasonic sensor for a LEGO train crossing?

I was looking at LEGO NXT components, and I found the ultrasonic sensor. I was wondering that if I put off to the side of the track, the nose of my train would activate the sensor, thus operating the ...
2
votes
2answers
66 views

Faulty NXT Motor

I have a motor that prevents the program from running. It simply allows a few slow movements forward with stops in between. It seems very stiff to rotate manually. Any way I can repair this motor?
2
votes
0answers
30 views

Train track switching using servo motor [duplicate]

My project requires using a servo motor for switching track. It needs to be automate switching points. Is this possible? What is the cheapest / easiest way of achieving this?
1
vote
1answer
168 views

Need help to identify minifigure

Can someone help me to identify minifigure linked below: I´ve been searching now about three hours without luck :)
5
votes
2answers
124 views

Opaque bricks with no center post?

What is the purpose of 1x2 red bricks without a post inside the brick? I know they often leave out the middle post on transparent bricks to make them look more window-like, but what about in opaque ...
1
vote
1answer
76 views

Teleoperated arm trouble

I have built a robotic arm with the lego Mindstorms ev3. My goal is to control its motion via teleoperation, that is , to have a gyro sensor strapped onto my arm and have the robot mimick the up and ...
3
votes
2answers
166 views

Substitutions for vintage hinges

I've recently gotten back into LEGO and I'm trying to restore old space sets (late 80's era) by buying parts on Bricklink. I've noticed that some of the hinge pieces are extremely expensive (e.g. ...
8
votes
3answers
9k views

What is the average price per piece?

Some LEGO pieces are probably more expensive than others, but what is the average price per piece of LEGO pieces, when sold as part of a kit? Is there any place containing statistics or graphs about ...
2
votes
1answer
89 views

How can I use the EV3 educational firmware instead of the retail version?

I have an EV3 brick from the retail kit, which is currently running the retail firmware. I would like to replace the EV3's firmware with the educational version. How can I do this?
2
votes
2answers
73 views

Resources to learn useful common Mindstorms mechanical construction patterns

I'm currently working on building a small scale CNC-like (X-Z, no Y axis) machine to cut glass mosaic tiles. I decided to give it a go using my EV3 set and I'm having some trouble with the Z-axis ...
3
votes
1answer
805 views

Where can I download the software for old RCX-era Mindstorms sets?

These days I've been coming across a lot of people who've purchased used MINDSTORMS sets from the RCX era, only to find they didn't come with a CD. And in order to use the set, assuming that using an ...
2
votes
1answer
115 views

Connecting a webcam to NXT and streaming a video

is it possible to connect any webcam or modify it in such a way that the NXT controller will be able to stream a video to another computer? Iv'e seen there are special sensors for it, but I can't ...
2
votes
3answers
176 views

What are some 3rd party mini-figure gun makers that distribute in Canada?

I'd like to buy some flint-lock era mini-figure guns for my collection, something like these guns. What I don't want is to pay the outrageous customs fees to get them to Canada. Does anyone know of ...
2
votes
2answers
293 views

How do can I tell if minifigures are custom-made or LEGO Originals?

I see that on Amazon you can find a lot of minifigures but I can't tell if they are cheap knock-offs or not.
5
votes
1answer
75 views

Convert 3rd party NXT programming language code to NXT-G program?

Is there a way to convert code from one or more 3rd party programming languages used for programming the NXT into a program that can be loaded up in NXT-G? If not, do any text-based languages provide ...
25
votes
14answers
5k views

Do LEGO bricks float?

Is it possible to build a boat out of LEGO bricks? I appreciate you couldn't make it watertight but would a LEGO boat float by itself due to the buoyancy of the bricks themselves? Pictures of any ...
2
votes
2answers
246 views

Vision Command and Exploration Mars software for Mindstorms RIS 2.0

I recently bought a set 3804 LEGO Mindstorms RIS (Robotics Invention System) v2.0 very well maintained but did not have the installation CD of the RCX program and IR tower. With some research on the ...
3
votes
1answer
115 views

Why are some of the supports on bottom of a lego piece hollow, and other are solid?

I've added an image of me holding two 1x3 bricks, one has solid supports (not sure the technical name...) and the other has hollow supports. Does anyone know the reason why they are different? Other ...
3
votes
2answers
97 views

Lego Motor for cycling a tool

I am curios to know if I can utilise the Lego Power range to rotate a transducer to a set point and return to its original position and if so is it able to cycle the movements repetitively? Ideally I ...

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