[Qbranch]

Remember, though timken bearings have ENORMOUS thrust as well as axial loading capabilities, there are some quirks about them i've found through a project I worked on recently.

Tapered roller bearings increase their resistance to rolling at a higher rate than a roller bearing does. Also remember that if using these bearings in a sideways orientation, the bearing won't stay together on it's own like a ball bearing would. Your design needs to allow for some kind of bearing captivation so that the shaft holds the bearing in it's ring.

Things I'm impressed with: Insanely little slop even with no pre-loading. I used a pair of 5.25" diameter Timken tapered roller bearings for a rotary pallet changer with an outside diameter of about 48". Even at the furthest reach of the the turn table, even without preload, there was only a few tenth thousandths of slop. About a hundred pounds of pre-loading corrected that... so in the end there was no detectable slop in the bearings even out at 24" away from the axle. While I was only after high rigidity in this application, a by-product of this was a load capacity about ten-fold that (balanced load) of which it needed to hold. In fact, I figured out the bearing pair I had made up could spin my car around, provided that it didn't have any gas in it. Timkens are really awesome in very high load applications as well as high-accuracy applications.

I have no practical experience with straight-roller bearings so... somebody else will have to pick up there.

-q