Good question for a newbie.
actually good question
I sand in two parts for the bigger stuff mostly.
I sand to about 100 before assembly then to 150-220 after.
if I am using screws, I set the holes, pull out the screws so some sanding
to 120, assemble, then finish sanding
It greatly depends on the joints, shape etc. You could sand a Jewelry box
after assembly, but a chair which has nooks everywhere may not do so well
especially if the wood came out rough.
The less hand sanding I have to do the better.
"Violin playing and Woodworking are similar, it takes plenty of money,
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