19
votes
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:
18
votes
Accepted
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 ...
15
votes
Accepted
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. ...
15
votes
Accepted
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-...
13
votes
Accepted
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.
13
votes
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 ...
11
votes
Accepted
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
...
10
votes
Accepted
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 ...
9
votes
Accepted
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 ...
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 ...
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:
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 ...
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
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 ...
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 ...
7
votes
Accepted
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.
7
votes
Accepted
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 ...
7
votes
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.
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.
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 ...
6
votes
Accepted
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.
5
votes
Accepted
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 ...
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 ...
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 ...
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 ...
4
votes
How do I increase axle speed using gears
You can't do this with the gears you've listed, but I'm not sure that you've listed the proper gears. I don’t believe that 32 or 64 tooth gears exist. I at least don't have any.
You can do this by ...
4
votes
Accepted
Lego Digital Designer: Having Gears Interact with Toothed Bar
The LEGO Digital Designer software does not have the ability to simulate the interaction of gears.
There is a similar software program called SR 3D Builder that does have this capability.
4
votes
Lego Digital Designer: Having Gears Interact with Toothed Bar
LDD is a design solution for static models. It is not a functional simulation tool. The gears turn with the crank handle if they are associated to the same group, but that is only because the gears, ...
4
votes
Accepted
Can you use a beveled gear as a pinion?
Seeing a picture of your progress would help tremendously. The way the question is worded, it sounds like you were wanting to drive the beveled gear directly from the servo to the rack at a 90 degree ...
4
votes
How can I assemble 2 opposing gears so that the axle rotations are perfectly parallel?
You could use a belt system to get a perfect, parallel rotation. The chain links used in this video are #3711 and the gears appear to be the same as the ones shown in your example.
There doesn't seem ...
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