Gary Fritz wrote in
:

I went over it with 150 and 220, and got it to a glassy-smooth finish.
But I apparently have troubles running my new random-orbit sander
right.

snip of some additional hard lessons

Well, after the ROS, at each grit, the procedure is to clean the surface.
Air, a soft bench brush, a shop vac, something. Then a quick wipe with a
rag, dampened with mineral spirits. That will show you what there is to
pay attention to.

With the ROS, I stop at 120 or 150. Everything thereafter is hand sanded,
with a block, to whatever the final grit is going to be. If oak, it's
often only 180, sometimes less, depending on what I'm going to do with it.

Someone said, probably more than one someone, that each grit is only to
take out the scratches from the previous grit. If you leave something
nasty from 60/80, then trying to take it out with 220 is a study in
frustration, and a waste of time.

If it were me, and it's not, I'd take a sharp card scraper, and go after
the spots with the swirls, then touch up the surface with the last grit you
used, only by hand, and with the grain, then clean and dampen the surface
one more time with the mineral spirits. That will give you the best
estimate of what the finish will look like, before you open another can of
poly.

Remember the patience part. Thanksgiving is still weeks away.

Patriarch