Spraying Oil Stains?
Article - August 11, 2008
This week’s question comes from Jorge who writes:
I’m finishing some maple kitchen doors. I have a Fuji Mini-Mite 3x to apply the finish. I first applied a 1.5 to 2 pound cut of shellac and now I’m spraying the oil based stain. The problem is that I get what I think is called orange peel. Basically I can see the stain dots in the doors. Definitely the stain is not applied uniformly. Here is what I’ve tried so far:
– Applied a thinner cut of shellac thinking perhaps the shellac was too thick. Initially I used a 2.5 to 3 pound cut.
– Sanded the shellac coat more aggressively using 220 grit.
– Adjusted the hell out of the gun. I adjusted the air pressure, fluid control, fan size and any combination of these three knobs with no success.
– I bought a #3 air cap thinking that the #4 was too big for the viscosity of the stain. No success here either.
– Thinned down the stain to 3 parts stain and 1 part solvent. This helped a little bit but still the result is not what it should be.
I’d appreciate any pointers you can give me because this thing is driving me crazy.
And this is my response:
Hey Jorge. Take a deep breath brother! I don’t think the problem is in the gun or your technique. Its in the materials. The shellac, even at 1.5-2lb cut, might be a little excessive in this case. Traditional oil-based stains rely on absorption into the wood to work properly. By sealing with 1.5-2 lb cut of shellac, you essentially created a barrier on the surface of the wood. So now the stain just pools, much like trying to use a marker on a glossy surface.
So here are a few recommendations. If you need to seal the wood first (which is not a bad idea for a blotch-prone wood like maple), just use a 1/2lb cut of dewaxed shellac. After it dries, sand it very lightly with 220 grit. This usually results in a surface that is only partially sealed and will still allow the some stain to absorb. So you can then spray on the oil stain, and wipe off the excess. Do not let it pool up. You may even skip the spray at this stage because all you really need to do is wipe the stain on. Now to be honest, I might even be a little hesitant to do this. I just don’t trust traditional oil stains over even partially-sealed surfaces. So for more predictable results, you may want to switch to a gel stain. The gel formulation does not rely so heavily on absorption and will give you a much better distribution and intensity of color, without any blotching. Once the stain dries, you can then apply the top coat.
Now going back to the shellac surface. Lets say you had that heavier coat on and you still wanted to add color. How would you do it? Well, you could always add some dye to the shellac itself. That’s a great way to bring some base color to the party. You could also add dye to lacquer (if lacquer is your top coat). I like to make very light dye mixtures (using both shellac and lacquer) that are mostly thinner and dye. But I like to add a little of the finish itself to the mix as that helps bind the dye to the surface. Basically, this is what is known as a “toner”. Hopefully that gives you enough to chew on. Good luck!