I was stupid enough to buy non-flanged bearing blocks for the THK rails for the long axis on my build. This means that, unlike the other axis, I can't use the actual bearing blocks as a jig to ensure precise hole positions for the mounting plates that go on top.
I partially got around this problem by using silicone mold putty and epoxy to make a copy of the bearing block surface to use as a jig. This works ok but, as I'm sure you guys know, if the position of the drilled and tapped holes are even a tiny bit off then the mounting screws don't fit, or get bent, or hinder the smooth motion of the axis.
The bottom line is that my drill press is not accurate enough to achieve the tolerances needed. The errors, while too small to detect with my eyes, are enough to cause issues. I have been making my mounting plates fit by drilling and tapping one hole to match the m4 threads on the bearing and drilling the second hole oversized to give me a little wiggle room. It works ok but it's not ideal.
How do you guys deal with tapped holes on mounting plates? Are you drilling and tapping precise holes and threads to match your bearings or are you using washers with oversized holes? Or am I the only idiot who bought bearing blocks with no flange?
I would have thought that THK or IKO would have sold pre-drilled mounting plates or "stages" to match their bearing blocks but I can't find any for sale as individual parts. I only see them on pre-made linear actuators like this:
https://www.ebay.com/itm/LINEAR-STAG...G8MJRWBarTIuxw
It would save a lot of time if you could just search for a mounting plate for an SR20 or SR15 bearing blocks....