Sanding sealer, end grain and lacquer

Grain fillers

Bill Tindall, E.Tn.

There are products called grain fillers. Their purpose is to fill wood pores in cases where a glass smooth finish is required for a porous wood-mahogany, walnut, oak, etc.

The problem with the spray can of lacquer is that it is formulated with very low solids. Hence, it will take a multitude of coats to act as a filler for it was never intended to fill this role.

When applying one finishing chemistry over another, adhesion and shrinkage must be compatible between the layers or down the road you will be refinishing.

I don't know a reliable way to proceed from where you are at. But I will offer this advice. Stop doing chemistry experiments on the finished product. Whatever you attempt next, prove its efficacy on a test piece.

different options

Michael Dresdner

It's unwise to layer sanding sealer between coats of lacquer as it can cause chipping and cracking. The best way to fill pores is with pore filler. The best ones are neutral, which makes them compatible with all finishes, and inert, so they won't shrink at all. My favorite is either Timbermate or GoodFilla (essentially identical) which are completely inert and contain no binders or solvents beyond water. Thus, they can be colored with almost anything, are compatible with just about everything, sand very quickly and easily, and are made to work either on raw wood or sealed wood.

That's assuming the pores are still open enough to hold filler. If not, simply use thicker lacquer after sanding back aggressively, but don't change materials in mid stream.

One thing I always do with any piece that has both end grain and flat grain (and that means all turnings) is to apply the first coat of finish, no matter what it is, using the "flood on, wipe off" method. That allows end grain pores to absorb as much finish as they need to fill and seal, but does not build up finish unevenly on the flats. In this case, since the oil you used has little or no ability to seal pores, the first coat would have been the lacquer, and yes, you can flood on and wipe off lacquer. Still, I would probably have used pore filler after the oil, or at least right after the first coat of lacquer.

One more thing: Rattle cans contain mostly solvent. While typical lacquer is sold at 25% solids, making it a relatively slow building finish, rattle can lacquer is typically at 6% or lower, making it a maddeningly slow build. For your flood on and wipe off, use liquid lacquer, not rattle cans. After you get things filled and smooth you can switch to rattle cans for spraying.

Re: Grain fillers

Michael Foster

Thanks Bill. I was reluctant to use the sanding sealer for just the reason that you stated. Afraid about the future of the finish. I normally do not use a finished piece as a test, and thought that I'd be fine with enough coats of the lacquer, but there are some persistent open pores. I am gong to try the brush on lacquer as suggested by Michael below and hope that will do the trick.

Re: different options

Michael Foster

Wow. Did not expect advice from the expert (I have your book and reference it all the time). I usually do the flood and wipe as you outlined on turned work. This is piece has been a bit of a stretch all along and presented some unusual challenges due to the way I chose to orient the wood. I am definitely going to get some of the filler you suggested as that sounds to be just the ticket I was looking for. I think I will try a coat (or few) of brush on lacquer rather than resort to experimenting with the pore filler on a half finished piece. The pores are filling, just some were larger than others and taking more time. Thanks for the help