Unanswered Questions

149 questions with no upvoted or accepted answers
16 votes
1 answer
916 views

How much tension can I expect to get out of a LEGO chains 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 16-tooth gear to directly drive a 24-...
10 votes
0 answers
201 views

How To Ensure Only One Brick is Fed Into a Lego Sorting Machine at a Time?

In this video, they create a machine that can take a bunch of legos put on to a conveyor belt and, using a camera, sort them into a number of categories. I am building a (smaller) version of this, and ...
9 votes
0 answers
129 views

When did LEGO start adding a progress-bar to build instructions?

Set #40549 has a stud moving along a progress bar at the bottom of each pair of pages, as you move through the instructions. The stud moves left to right. I've never seen this in any other ...
8 votes
0 answers
216 views

I got a vintage roof brick that is very nice but can’t find what it is?

I got these parts in a lot, but can’t find any history or brand or set on them?
8 votes
0 answers
206 views

Are LEGO Quatro compatible with larger bricks? Soft Bricks or other?

There is a nice discussion here on LEGO+Duplo+Quatro compatibility. I posted what I found here where a LEGO storage block is the right dimension to be double a Quatro (4x Duplo, 8x normal). However, ...
8 votes
1 answer
206 views

Motor problems in 60051

The motor in my High Speed Passenger Train set (60051) has stopped working properly. I just put brand new batteries in and it acts just like if they were worn. Moreover, the little brown capacitor ...
7 votes
0 answers
204 views

Digital tool for roller coaster physics

I'm currently working on a roller coaster MOC with a looping. I started physically building the MOC but quickly recognised that it is quite a mess to build something, tear it down rebuild it, etc. ...
7 votes
0 answers
153 views

Oil for old 4.5V motor? (UK)

I've just got my old LEGO Technic motor from my loft. It works but squeals in a way I don't remember it doing (35 years ago). I assume some lubrication would help and I've seen references to 3-IN-ONE ...
6 votes
0 answers
143 views

Looking for a PC controlled motor that allows for very small and precise movements

The image below is a LEGO specimen stage designed for a stereo microscope. I am looking for a recommendation for a PC controlled motors that allows for very small and precise movements. I want use ...
6 votes
0 answers
189 views

Was the color variation on 1970's transparent pieces really that bad or are mine unusual?

Having gone through a bunch of old 1970's Lego (I rebuild all my original sets during the Covid lockdown) I noticed that color-less transparent bricks and slopes have a lot of color variation to them. ...
6 votes
0 answers
186 views

Fix Lego M Motor - The hooks aren't budging

I have a Lego M motor that is broken. I'm following the instructions here to try to fix it but the little tabs that hold the plastic frame together just won't budge no matter how hard I'm pushing them ...
6 votes
0 answers
190 views

What is the number printed under the barcode of a Lego set?

I’ve got two sets of Lego Ideas #025 (steamboat Willie). They have the same barcode. Underneath the barcode there are some small numbers: one box has 118789 970, but the other box has 118789 017. A ...
6 votes
0 answers
656 views

Building instructions: Robot Spider Pen by Ricardo Oliveira

Some time ago I found the following youtube video by Ricardo Oliveira of a small NXT plotter that crawls over a whiteboard. It has two strings that can be shortened through coils and with this, it ...
6 votes
1 answer
222 views

Toa Terrain Crawler alternate build instructions

I was building the LEGO Bionicle Toa Terrain Crawler, (8927), when I saw at the back of the instructions a photo of an alternate helicopter-type build. Where can I find the instructions on how to ...
5 votes
0 answers
136 views

How can I prevent rubber bands disintegrating?

These two answers partially answer this question., but I think it's worth its own question to find more options in a more comprehensive answer. Old Lego rubber bands are known to become brittle over ...

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