Originally Posted by
ger21
With the easy way of using bearings mounted to angle on round pipe, the loads on the bearings are at a 45° angle. On my router, I use threaded rod to pull the bearings tightly to the pipe. But with the 45° load, the bearings qickly start to bind, so you can't really put much preload on the system. And this preloading adds a lot of friction.
And also, when you do put a lot of preload on the bearings, the bearings will quicly wear flat spots onto the pipes due to the small contact point.
Both of these issues showed up as soon as I mounted my gantry. And neither exist with this design. The bearings carry radial loads only, which they're good at, and the contact area is much greater on the flat rail opposed to round ones.
I'm trying to develop a very solid machine that any woodworker with a decently equipped shop can build, without needing a CNC to cut the parts out. I hope to have my router running this fall, then I'll stat building a prototype of the new design. I'd like to have a full, complete set of drawings before I start, so I'm starting now. I have a lot of projects I need to complete before I get there, but I can work on drawings a little each night.