Max wrote:
I've been sanding down to 220 on Oak. I have some 320 discs but I can't
see/feel where 320 is any improvement over 220. On some of the softer
woods it seems a little smoother with 320. Is there any consensus on
how fine one should go?

Depends on the wood, the finish, if you know how to sand, as well as if
you're staining.

My normalities:

Oil and thin clear finishes:
Open grained hardwoods and softwoods (Red oak and pine) - 220
Tight grained hardwoods - 320-400
Exotics - possibly 600

Staining:
Most woods - 120-150, maybe 180-220 on closed grain wood
End grain - 220, or a grit higher than the face

The important part of ending at a lower grit pre-stain is to be aware of
cross grain and orbital scratching. You CAN stop at 120 before staining
IF you hand sand with the grain. Closed grain woods may require 150-220
grit to avoid obvious scratching. Sanding to too fine of a grit
pre-stain may result in pigment wiping right off, and a too-light final
color.

Barry