Expert: Jamie Yocono - 10/26/2010

Question
I was given and old bookcase. I have stripped it twice with the citrus remover. Problem...there are black rings on the top. I believe this was motor oil or paint cans.???? It is solid oak and was in a garage for about 30 years....help

Answer
Hi Brenda,

Don't you hate it when that happens?

I think the stain, since it's black, is a water stain rather than anything else. Oak contains tannic acid, which reacts with water to create black stains. If it were a from motor oil or paint, it would appear shiny and probably not accept any finish, since those would seal the pores of the wood. But the way you described it, it's a water stain. What a pain!

There are two methods for getting rid of the stain, and neither is very easy.  The first method would be scraping or sanding the wood. The alternative is bleaching the wood.

There's a chance it's not stained very deeply in the wood, so you might try a little spot sanding with a detail sander. Better yet, instead of sanding, you could scrape the wood lightly with a very sharp chisel. Sometimes, when I have a large area to scrape, I even use a sharpened plane blade. Do you possibly have one of those? If you've never scraped something, it's a skill to be mastered slowly. You basically hold the chisel or blade nearly perpendicular, or at a slight angle toward you, with the bevel facing away from you. Then - scrape the area slowly, pulling the chisel or blade toward you. Just go in one direction, don't go back and forth.  This is a far superior way to clean up wood defects as opposed to sanding. So if I had your stain problem, that's how I would deal with it.

The second method of bleaching would be really labor intensive, and may not even work, but I've had some success with wood bleach, so I thought I would mention it. Here's a link: http://www.idealtruevalue.com/servlet/the-16883/Detail

You can find it in a powder form at most woodworking supply stores like Rockler or Woodcraft, or at a Sherwin Williams paint store.(Regular household bleach won't work; it's too weak a solution.)  You mix it according to the directions, and then apply it to the wood. It bleaches the black stains with a decent degree of success, but may make the area lighter than the rest of your wood. So you would need to take some care here and not be messy or you could have splotchy wood.

OK, I hope that helps. I know both of these solutions probably aren't what you wanted to hear, but at least you know what you need to do. Feel free to write again if you have any other questions. Good luck.

Jamie Yocono
Wood It Is! Custom Cabinetry
Las Vegas, NV
www.wooditis.com