With thinned coats for all coats your build will be

less per coat so more will be needed...



John

It is not really appropriate to build for a flat surface using a film finish (varnish, lacquer, shellac, poly). If you want flatness then use grain filler. Finishes that thick will crack\craze over time most likely.

If you are applying enough finish to flatten red oak you have developed a slab of plastic over the wood.

I finish cherry with a few coats of wipe on poly and until I wax it, you can still feel the grain even after sanding the wood initially with 320.