Working with Oak, for most woodworkers is a joy. Despite the fact that Oak is a heavy wood to work with, it produces such excellent finished results it is hard to avoid using it. One of the beauties of Oak is that it can contain visible “figure”, that is, areas where the grain runs a bit different than normal creating a pleasing pattern. These pleasing patterns can sometimes have their own problems when it comes to finishing.
One of the biggest problems we see with projects that are made from Oak is the miss-matching of grains. If you want to get a good finish on any wood project it is imperative that you try to match the grains as best you can. For example if you are creating table top or the side of a bureau, all the wood you use should be flat sawn, quarter sawn or rift sawn – NOT some of each. Each cut of wood absorbs stain differently which means, depending on the angle of light and the angle of view, the stained wood can appear uneven or mottled.
The second most frequent problem we see, is lack of finishing. Oak needs to be finished with very fine sandpaper like 280 or 320 grit in order for it to look nice when the final finishes are applied. The sanding process, particularly with finer grits will also create sawdust that will linger in the open-grain of the Oak. To remove this completely we recommend at the very least a tack cloth of mineral spirits, or to use your compressor and actually blow the dust out (this would have to be done out-or-doors for safety reasons). Only by getting all the sawdust out of the open pores of the Oak can you be assured of some success in your finishing.
Once you have “prepared the Oak” that is sanded with finely and removed the sawdust from the pores, now is the time to decide how you will finish your project. Do you want a natural clear finish, or do you want the oak stained a darker color, perhaps to match other projects? In terms of finishes you can select either water based or oil based finishes and stains. To compound things further coloring the wood can be done with either dyes or stains, and stains can contain filler or not (filler is used to fill the open pores of the oak to make a smoother finish).
Newer formulas for finishing oak suggest that wood dyes be applied and then over top of that, a “sealing” coat of de-waxed shellac (note, it MUST be de-waxed), and then on top of this a “glaze” is coated on the wood. A glaze is simply oil based stain and filler. What this process does in effect is work on the contrasts of the Oak and it's pores by making the pores stand out a bit more thus making the grain more visible. Then of course there needs to be a final finish of some sort of a oil based varnish or other similar top coat. The results from this process is indeed a lovely finish.
However you decide to finish your Oak project, there are 2 things to remember, 1) fine sanding is imperative to getting a fine finish and 2) always test your finish on another piece of wood BEFORE you give your project it's finish. There is far too much work in having to remove all the finish off a project that you are not happy with rather than testing before you begin ANY finishing on your project. We have seen far too many project with inferior finishing techniques that then disappointed the woodworker. Play it safe, take your time and know what to expect before you jump in and start the final finishing proeces.
Copyright - Colin Knecht