Has anyone considered building Ball diffs instead? One could relatively easy build the hubs for steel diff plates and the ball bearing holder. I see the plates cost about 5 euro each, and the balls are somewhere between 5 and 10 euro.
That should hold up under power, but from reading the other responses it appears that the bevel gears are not the part that fail, which would make that solution moot.
A ball diff will need a bolt and springy washers to make it easier to adjust. Also, be sure to use diff lube when assembling.
A ball diff might heat up enough to soften printed parts if there is is enough slipping or wheel spin. I think it’s worth proving me wrong to get a diff that’s not wide open.
Ball diffs are a nightmare to tune and get right, I wouldn’t waste time with them… too loose and the friction causes them to heat up and chew threw gears. too tight and they don’t turn properly. fluid filled viscous coupling is much better.