Some will possibly disagree; however, the results speak for themselves. I prefer to use 600 grit paper to sand between coats of dewaxed shellac used to seal white oak:
As I have mentioned before, one key item in a finishing schedule is having the right sandpaper, like 3M’s 216U Fre-Cut™ Gold. I discussed the use of this paper in an earlier article; but I still must remember how critical it is to have the proper tools to do the job. And in finishing, this paper is an essential tool. The surface of the white oak is silk smooth after sanding. The smooth surface will telegraph into the sprayed varnish, yielding a very nice, smooth finish. Who said waterborne coatings were difficult to use?
Note: Sealing the surface of white oak and (especially) red oak is essential when using waterborne coatings. Avoid applying (typically) high-pH waterborne coatings directly on the raw wood surface of high-tannin woods like red and white oak, as pin-holing and bridging are likely to develop; that would make it difficult to get a nice, smooth finish.
Next: Attaching the top, and start spraying the varnish.
— Al Navas