I am planning to spray a dye (either water or alcohol) then use grain filler and a topcoat (Waterlox). The filler wants a coat of sealer (shellac) under it. My concern is that brushed or sprayed shellac will reactivate the dye, and create a mess. I've done a test on some smaller pieces (wood is mahogany), and its been somewhat manageable, but I think it will be a problem over a large flat surface. Any thoughts appreciated.