19
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How can I place a motor in the middle of a Technic beam with an odd number of holes?
I'd address this with bevel gears:
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18
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How can I place a motor in the middle of a Technic beam with an odd number of holes?
Something like this would work. Since this is just an idea pictured assembly doesn't feature any bracing required for this solution to work properly. Another thing to mention - 8T gears doesn't like ...
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15
votes
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Part identification: 40 tooth gear from The LEGO Movie
From this image, you can count the teeth well enough to determine there are actually 60 teeth, not 40:
This does not appear to be a real part.
It also appears you aren't the first to notice this. ...
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15
votes
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What's this round blue gear piece from set 76911?
This is a blue Non-Vented Double Dead-Ender Cap (or a variation thereof), also called a Luer taper/lock, sold by various OEM suppliers. According to the supplier KempCo Specialties, these are multi-...
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13
votes
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What is the "Module" of a LEGO gear?
Quick answer: LEGO gear module is 1 (metric).
See Section 3.4 at this link: http://bdml.stanford.edu/Main/CrawlerNotes
The consensus seems to be the following:
Lego gears have a metric module of 1, ...
13
votes
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What is the purpose of the 8 tooth timing gear?
When looking at Blakbird's Technicopedia page for this Technic set, this part is indeed used as a rotary encoder in combination with the bar code scanner.
See the last entry on the page.
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13
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What's this round blue gear piece from set 76911?
Ok everyone, I have a disappointing update but it does answer my question. I didn't actually get round to contacting Lego about this because I mentioned my discoververy to my mum first. She ...
- 517
11
votes
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What are the dimensions of a technic axle?
I found CAD files for LEGO technic axles here: https://grabcad.com/library/lego-technic-axles-1
and some gears which have holes for technic axles here: https://grabcad.com/library/lego-technic-gears-1
...
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10
votes
How can I transmit horizontal torque to vertical?
I'd like to cover two other techniques that work well, they both transmit horizontal torque to vertical but in slightly different ways that I believe may be useful for different situations.
Worm ...
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10
votes
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9398 4x4 Crawler front wheels rotate in the opposite direction to the rear wheel
Likely you'll have the differential gears oriented wrong in the front or back section.
The differential gear is this piece:
Please check the instructions carefully and see if the orientation of ...
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9
votes
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How can I assemble 2 opposing gears so that the axle rotations are perfectly parallel?
How can I get 2 opposing gear's axles to be perfectly parallel? Are there any good workarounds?
You could use an idler gear. It will even out the offset.
Yet, at the same time, it (or any odd ...
- 2,498
9
votes
Grand piano page 269 of instructions - are the gears suppose to stop after a quarter turn or keep going when reversing directions
Tl;dr - Your piano appears to be functioning correctly. The step you mention appears to be resetting the gear to a known position. The playback direction is clockwise and free of restriction. The ...
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8
votes
2:1 gear ratio in stud-less Lego Technic
Here's a solution I found in Yoshihito Isogawa's LEGO Power Functions Idea Book Vol. 1 - Machines and Mechanisms:
EDIT
based on Eric's comment:
And here's using the black piece from JohnnyB's tweak:
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8
votes
2:1 gear ratio in stud-less Lego Technic
I felt my original answer got messy. The simplest answer is that you already had it. I experimented with variations of your 12T/24T build and experienced varying degrees of the stiffness you ...
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8
votes
Why does this "useless machine" use out of production parts?
Because the builder had those parts, and knew how to use them.
Perhaps those parts weren't out of production when that was build. There are extremely few MOC's that are updated when the parts go out ...
7
votes
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How to build a limited slip differential?
If you haven't seen it, Sariel's limited slip differential technique might do what you want, but it's a little different than what you are asking for:
This setup doesn't provide a clean way of ...
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7
votes
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Which combination has a lower gear friction?
According to Sariel's gear tutorial in chapter 5, Efficiency:,
- the less gears, the better
- the smaller gears, the better
Based on this principle the first setup looks the best, but you are ...
- 14.7k
7
votes
How can I assemble 2 opposing gears so that the axle rotations are perfectly parallel?
If you use a crown gear or bevel gear to connect your gears twice perpendicularly, they are exactly opposing each other, turn in opposite directions, and are parallel (if the respective axle is ...
- 2,164
7
votes
Insert a gear into a turntable?
I'm struggling to understand why would there be a need to insert 24T gear inside turntable gear. If you need rigid connection - it is best to use existing attachment points for you assembly.
Internal ...
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7
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Insert a gear into a turntable?
Indeed I had to disassemble it (which went without much effort) but the 24 tooth fits fine:
It can slip up or down for about half a stud but is stuck otherwise.
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7
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Why does this "useless machine" use out of production parts?
There is no universal LEGO Technic set that contain each and every gear LEGO has ever produced.
None1 of those elements are out of production. You may not acquire all of them in a single set, yes, but ...
- 21.5k
6
votes
High Torque Subtractors
It sounds like you need a stronger differential.
Might I suggest this design by Nazgarot:
If you make two, you can build a big and sturdy subtractor like this (probably customizing the gear ratios ...
- 13.3k
6
votes
Does LEGO Digital Designer include part 4539880?
Yes, but only one color choice of light bluish gray is available in the default mode.
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6
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I am building the LEGO 42131 D11 dozer and some of the parts are moving in reverse when testing
I had the same problem but turns out the app graphics are just wrong. Completed the build and it works perfectly fine.
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6
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Error correction after building the D11
I made a major rebuild of the D11, opened the gearbox and found this orange little piece in a false position.
After the correction the D11 run fine.
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5
votes
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Which system is more efficient?
The torque in both versions would be the same.
Your first version just adds 3 of these gears:
The ratio between them is 1:1 so it will be the same as if you connect the axle straight into those ...
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5
votes
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What does "No Friction" mean in Parts "Gear with 8 Teeth Wide, Notched and No Friction"
In the case of this item, it means that the gear will slide freely along the axle it rotates around.
- 3,269
5
votes
Technic Rough Terrain Crane (42082) doesn't move
Motor is only being used to operate the crane, not to drive the model. So driving/pushing shouldn't be blocked at any time. I suspect there will be an issue with position of differential - if placed ...
- 21.5k
5
votes
Gearbox doesn’t move when it’s in neutral - Is that normal?
The point of the neutral position in a gearbox is that it disconnects the engine from the drivetrain. Therefore no movement is expected at the wheels when the engine turns and vica versa. If the ...
- 14.7k
4
votes
Any tips for aligning gears in LDD?
Use math.
Here is a simple example... Suppose we want to line up two 8 tooth gears. Start by placing two axles and one of the gears...
Since there are 8 teeth on the gear, we can figure out that the ...
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