Ballscrew Support Bearings - Angular or Self Align or ??

[williamturner1]

Hey.

So I've been a sleeper CNC builder for the last 6months. Built many machines ... in my mind ... sketched the best on paper ... and CAD drawn only a couple of the ones best compromise between material costs + parts.



I've got a motley collection of parts (which above design is based on) and am almost ready to ask you guys for feedback on my build design ... but before I do ... im battling with some small details I would really appreciate some help with.

BEARINGS
What do most people do to solve the: "how to support the ballscrew + minmise axial play" problem?

For instance what has HiltonSteve done in this machine?





I appreciate you can use angular bearings like so:


and fitted like so:



but that is quite a bit of work + parts ... spacers, preload nuts, making retaining plate, etc. and angular bearings are very expensive

I got quotes (Brammer) 12mm bore x32x10 £28 but I would need 6 (xAxis=2x2 + zAxis=2)
which is before the other parts


SELF ALIGNING
Is the axial missalignment of bearing block vs ballscrew an issue I should be concerned about?

ie. Bearing housing not perpendicular to balscrew through error in drilling the bearing housing to base surface mount holes

I am assuming not as I've not see any evidence of people using self aliging bearings be it in a off-the-shelf pillow-block housing or to a self-fabricated housing
eg.


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So basically Im sure there is a simple solution but I can't tell what it is from looking at the designs.


MANY THANKS!