Originally Posted by
Granpa
Sorry about the anvil stuff. Glad you liked the hinge pin solution, but to give credit where credit is due, Deven White came up with that one.
I just cannot bring myself to accept the need for a spacer between the bearings. If Tamiya parts are used, either kit or option, there is so much play between the hex and the bearing there is just no way the bearings could be squeezed together. If you place a shim that is much over 0.6mm thick, the wheel will not spin freely. I'll bet you that 99.999% of modelers would take out shims till the wheel spun freely. Therefor no squeezed bearings. You're probably right on the distributing load bit though.
I also tried to figure out how to make such spacer cause it would have to be very precise in width and square. Too short it's useless. Too long and the bearings won't seat. First, you would have to locate material to make this spacer. Next measure how wide to make which for me would be a problem. Then you'd have chuck the spacer material in a lathe and cut off the proper amount ---no lathe in my shop.
Just kiddin' you a bit, but really how would you make that spacer and meet the precise dimensional requirements.
Don't be sorry. I loved it. You have real literary talent. No joke. I amuse myself with that. Brilliant. Sensitivity of an anvil, hehehehe!
I am not at home now, but I will check and hopefully find one car I can demonstrate on.
Oh, I use driveshafts (double cardan joints) by the way. But I seem to remember I had this problem with kit axles too.
Here's how I do it.
I break an old worn bearing of the same size. Take the inner race, cut it "close enough" thickness wise with a thin Dremel disc. I then put the ring in a hole of close diameter in a piece of flat bar of the thickness I need to end up with, place the flat bar with the ring inside on a hard flat surface, and take a piece of sandpaper (coarse) and "grind" it down. Test on the car, if it needs to be thinner, I add one shim of appropiate thickness under the ring (in the hole in the flat bar) and sand some more. When you get close, you swap to finer and finer sandpaper. I can get anything ground to any accuracy you want that way. And the squareness is guaranteed by the hole you stick it in being perpendicular to the flat bar and of very close diameter, so the ring can not wobble inside, as well as the bottom face of the bearing race (which of course is square). Also, the thickness is guaranteed by the flat bar which you simply can not sand down more than a fraction of a hunderdth of a millimetre (beyond measuring). Using the shims inside can basically afford you the accuracy of the shim. The sandpaper I usually glue (contact adhesive in spray can) to a flat piece of bar again. When it wears out, I just peel it off and replace.
But if I find a round bar of the right diameter lying about my shed, I jam the ring on it, stick it in my lathe chuck and spin it in reverse whilst with the dremel (clamped to the tool carrier) and with a cutting disc (thin, using the side) I grind the ring perfectly round and at the right thickness. Finish off with fine sandpaper.
Piece of piss, really.
And true, I use shims on the axles. Especially on Yokomo axles which allow adjustment of the track that way.
the end result is that my wheels spin freely with no play at all whatsoever.