I recently built a custom tank and had some issue with gears and axles.

The tank is probably heavier than it should be so there is a lot of friction and I am struggling to prevent the gears from grinding. There are two sets of reduction for motor. I have tried to holding the sets together using liftarms but at higher torque they seem to struggle anyway.

The second issue I have is with the axles connecting the independent treads to the body of the tank. Since the treads are suspended the axles are the only thing holding it. That is not optimal as the treads spread out or even come off. The suspensions don't seem to hold much, probably due to their "mobile" nature.

Any suggestions on how to solve these issues?

Here are some pictures for reference: https://imgur.com/gallery/tL4erYo

The tank looks rad

Have you got any pics of the underside? Some pics without the tracks would also help.

1 hour ago, suffocation said:

The tank looks rad

Have you got any pics of the underside? Some pics without the tracks would also help.

Thank you.

I've posted some more pictures here: https://imgur.com/gallery/kn4hDSm

Maybe replace that L-shaped beam with two 3x5 thin triangle lift arm, and then securing the extended part the the bottom of the frame?

Currently all you have is the friction of one axle to hold on a pretty large track assembly. I'd be looking at ways to incorporate a small turntable for each set of tracks to pivot around, it'll be smoother and more secure.

It's always going to be a problem to go from an XL motor to an 8 tooth gear, but you've exacerbated it by leaving that half stud of space and so the teeth of an already weak gear are only half contacting each other. You might do better by skipping that first reduction. Put the power through two pairs of 8 tooth gears instead; spread the load more.

If you could somehow implement these

at the pivot points, it would take most of the load off the drive axles.

Also, those z8 gears seem to be having a pretty miserable time. I reckon most of the torque you gain from the 5:3 reduction is lost in friction, so you might as well drive the knob gears directly. One last thing which could be tricky, though, is to replace the knob gears with stacked half-bevel z20s and z12s.

You would be better of using the new stronger 8T gears

Does skid steering work with a track length that long? Have you considered pivoting the tracks, like in 42069?

7 minutes ago, pleegwat said:

Does skid steering work with a track length that long? Have you considered pivoting the tracks, like in 42069?

Yes, skid steering works fine. 

42069 looks neat but would add more complexity to the model. 

First of all, two z8 gears without support on both sides, need to be reinfiorced to work properly. Second, get rid of them, because it is you weakest point.

 

Just now, M_longer said:

First of all, two z8 gears without support on both sides, need to be reinfiorced to work properly. Second, get rid of them, because it is you weakest point.

 

Yes, I figured that out.

On one side they're half ground to dust ?