90 degrees liftarm connection techniques

[fmkamchatka]

Hi everyone,

I'm trying to build a tracked vehicle by myself. See the attached photo.

I'm trying to find the right way to attach the orange liftarms rigidly to the existing structure (motors + red liftarm), but I have trouble finding something elegant and rigid.

I have looked for techniques in existing set instructions, and in some books (Tora no Maki) but I haven't really found something that translates well here.

Would anyone have some advices or even good resources (videos or blogs) to help me here?

Thanks!

Arthur

[Conchas]

You can try to play with any of the Technic frames, for instance.

https://www.bricklink.com/v2/catalog/catalogitem.page?P=64179#T=C
https://www.bricklink.com/v2/catalog/catalogitem.page?P=39794#T=C
https://www.bricklink.com/v2/catalog/catalogitem.page?P=39790#T=C

[Jurss]

It just impossible in one stud level, bracing is needed in different directions. Gears are also needed to brace, now they will be pushed out and clicking under load.

Not the best solutions, but maybe would help with ideas

[MOC] My first tracked vehicle - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums

 

[Stereo]

I would probably turn the white L-brackets around so they connect the beams, but also in this situation it seems better to have the motors directly drive the tracks instead of using any gears.

[howitzer]

Yeah, having motors directly drive the sprockets without any gears would definitely be better, though then they'll also turn quite fast so there's speed to consider and that might require reduction with gears. You could position the motors side-by-side facing opposite directions and then use gearing to bring the power to sprockets with reduction as needed. Also consider that the motors have many pinholes and are very sturdy, you should find ways to use them as structural elements in addition to beams and frames.

[Erik Leppen]

Spur gears (straight gears) are less likely to click than bevel gears, so if you need gears to change the speed, I would suggest using spur gears.

If you want to keep the current situation, then maybe you could replace the red beam by a 15x11 frame (surrounding the motors) and change how the current gearing is connected. Use the vertical holes in the frame to connect everything securely.

[Carsten Svendsen]

I'd suggest using the flip-flop beams so that it is easier to brace out with some 3x5 liftarms 

[gyenesvi]

I think in this case, it would be simpler to use the motors as structural elements, and connect the tracks to their sides (start with a 2L beam on the motors to create mounting points in the middle). Then cross brace the whole structure above/below. Flip flop beams can be helpful for that indeed.

It's actually ridiculous how hard it is to build such simple structures out of technic parts. The system is clearly missing many connector types.

Edited June 29, 2024 by gyenesvi

[fmkamchatka]

Thank you all.