I don't know if anyone else had any issues using these cups, but it almost seems like they are too long to allow you to shim them properly. Maybe I can take an exacto and separate the seal/gasket and only use half of it to give me some wiggle room for proper shimming... just had that thought as I was posting this. However, that would possibly make the internal gear lash too tight...
As it is, I cannot fit a shim on the ring gear side at all. It just won't go in without destroying it. Even after assembling it, I pried on the gap between the case and ring gear with a screwdriver to see if it would move at all, it doesn't. My only option was to shim the pinion and it grazes the surface of the diff cup. Even then, the mesh isn't as tight as I'd like it.
You can see how much I turn the input back and forth to see the gear lash about 3/4 through this. It's a brand new bulkhead, ring/pinion/internals/shims internally.
I upgraded the cup in the center too. I didn't bolt it to the chassis, I just put the top cap on and tightened it up and it almost seems like the bottoms of the legs are going to be too far apart and when I screw them onto the new chassis tomorrow, it's going to crush the bearings.
I'm using the gaskets that came with the cups... perhaps they are too thick? Can't imagine I'm the only person having this issue. Or I'm just doing something really wrong.
This is the case:
https://www.arrma-rc.com/part/ARA220050
Also, in the diagram, they show that you should use 2 shims under the larger sun gears. I have the mugen big shim under there and there's no way another shim is going to fit on top of that. Not without distorting the shim once I hammer the pin in there.
As it is, I cannot fit a shim on the ring gear side at all. It just won't go in without destroying it. Even after assembling it, I pried on the gap between the case and ring gear with a screwdriver to see if it would move at all, it doesn't. My only option was to shim the pinion and it grazes the surface of the diff cup. Even then, the mesh isn't as tight as I'd like it.
You can see how much I turn the input back and forth to see the gear lash about 3/4 through this. It's a brand new bulkhead, ring/pinion/internals/shims internally.
I upgraded the cup in the center too. I didn't bolt it to the chassis, I just put the top cap on and tightened it up and it almost seems like the bottoms of the legs are going to be too far apart and when I screw them onto the new chassis tomorrow, it's going to crush the bearings.
I'm using the gaskets that came with the cups... perhaps they are too thick? Can't imagine I'm the only person having this issue. Or I'm just doing something really wrong.
This is the case:
https://www.arrma-rc.com/part/ARA220050
Also, in the diagram, they show that you should use 2 shims under the larger sun gears. I have the mugen big shim under there and there's no way another shim is going to fit on top of that. Not without distorting the shim once I hammer the pin in there.
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