[Brandon Holley]

Originally Posted by Cory

The diameter of the drill itself may be ground more precisely than on a cheapo drill, but the geometry of the tool inherently prevents it from making extremely round/accurate sized holes.

In addition to this, any sort of runout on the drill/lathe/mill you are using will compound these issues.

Reamer is the way to go if you want to have repeatable results from plate to plate. Drilling holes, milling them, laser cutting them or waterjetting them will all result in a different sized hole for the same "as designed" size.

The best way to deal with it is to ream.


One understated method of holding bearings in is green loctite (gap filling). Having the bearing slip fit inside a hole, and using appropriate green loctite does a good enough job of holding bearings in.

Also- the ball bearing/ball peen trick is a nice one if youre in a bind. We have a nice 1.5" diameter steel ball bearing. If a hole is a little bit too large, we can just stuff that bearing into the hole and whack it with a hammer. It creates a little curl of material just big enough to bite the bearing and hold it in place.



-Brando