Finishing Quartersawn White Oak
Article - May 15, 2007
This week’s question comes from Jeff. He writes:
I am almost complete on my commission of a quartersawn oak barrister cabinet. I am now ready to apply the finish and am looking for a way to make the ray flecks really “pop”. The customer is looking for a medium color in the white oak. If you were building this cabinet, how would you go about making the ray flecks really stand out?
And here was my reply:
“There is no doubt in my mind that the best way to make the ray flecks “pop” is to do a classic ammonia-fumed finish. First order of business is to attain some aqua ammonia. I got mine from a local pool/spa supply but many people have luck going to a blueprint supply house. You need to build some sort of airtight (or near airtight) tent outside. Do not be tempted to do this indoors. I usually drape plastic sheeting over the project and make something that resembles a tent. If you can build some sort of makeshift frame that would be even better. But build the tent in such a way that you have one access point that you can occasionally open and close. Now before going any further, we need to discuss safety. Aqua ammonia is dangerous stuff. Without the proper precautions things can go badly real fast. So you will absolutely need a respirator with an ammonia-filtering cartridge, sealed eye goggles, and gloves. Its a good idea to cover all exposed skin as well. Pour the ammonia into a shallow pan or two and place these inside your tent. You also want to put a test piece of scrap wood in the tent as well. This is your color indicator. Seal everything up and wait about an hour or so. Pull out your test board and see if the color is where you want it. The color change happens gradually and depending on how well sealed your tent is, you could hit your desired color as fast as an hour. So check the board every hour or so (with your protective gear still one). But the idea is to catch it at just the right color and remove the ammonia. Then open up the tent (with your protective gear still on), and let the wood air out. You are probably best off leaving it outside overnight. The color will appear a bit grayish. Don’t worry, it will look beautiful once we add some finish. Here is my finish schedule: one coat of amber or orange dewaxed shellac (2lb cut) to seal the surface. Sand lightly with 320. Then apply a dark brown glaze and wipe off the excess. This will put a nice dark color into all of the open pores. Let dry overnight. The next day, apply another coat of the shellac to seal in the color. Then for some extra protection, I like to add a few coats of a wipe-on varnish. When its all done, the finish should look something like this: Q-Sawn Hall Table
Now if you are even slightly uneasy about working with the ammonia, consider some of the other finishes that are designed to mimic the fumed look. Here is a great example: Jeff Jewitt’s Mission Oak Finish