zobsky asks;

red) oak is a rather open grained wood. i'm thinking of finishing it
with tung, but am worried about how to conceal the open grains.

Filler. Behlen's Por O Pac is the style I'm most familiar with. You can also
mix up a slurry of sanding dust and your finish (assuming you're notlaying on a
super fast drying finish) and apply that. Force it down into the pores with and
against the grain, wipe it off, let it dry and check for any sanding needs.

Then finish. Tung oil or whatever you choose.

With the slurry method above, you stain first, sand lightly and use the stained
dust to fill. IIRC, Por O Pac comes in various colors, some of which may match
the color you want.

Charlie Self

"If our democracy is to flourish, it must have criticism; if our government is
to function it must have dissent."
Henry Commager