Applying a glaze on varnish

[Benoit]

I have a large built-in entertainment center. This was already there when we bought the house. The contruction is great. It is made of high-density particle board (this stuff is heavy!) with oak veneer. The veneer is quite yellow now, and we would like to give it a more contemporary look. I would like to have something that looks like a light color stain (so we still see the grain), in the gray-blue tone. But I don't want to remove all the varnish, that would be messy, smelly and take a long time... Can I apply a glaze directly on the varnish? Can the glaze really change the color from yellowed oak to a light gray-blue? Should I use something else?

My other option is to forget about the grain of the veneer, do a light sanding and paint everything with a solid color. Then create a faux-fini to give it some character. But that is more work, and I would loose the look of natural wood.

Thanks for your inputs! Benoit

[Josh]

Yes, you can. However, since the old varnish would have fully cured long ago, the new varnish will not stick to it directly. You'll need to rough it up with some 220 grit sandpaper so the new finish has some grooves to bite into.

A good option would be to buy a colorant that you can add directly to the new varnish. If you plan to use an oil-based varnish, get a dye or pigment which dissolves in mineral spirits. If you plan to use water-based polyurethane, get a water-soluble dye (aniline dye is a good choice because you can find a huge variety of premixed colors or you can mix your own starting with primary colors). Trans-tint dyes are a good option, too. They come in concentrated liquid form and are compatible with oil-, water-, and alcohol-based finishes.

Make sure you apply thin coats. I'm assuming you'll be brushing or wiping (as opposed to spraying) since this is a built-in. You can always build up additional coats to darken the color, but it's a lot harder to undo a coat that's too dark. Also, when brushing it's very easy to get too much finish in inside corners and various nooks and crannies. If you apply the color slowly over the course of multiple coats, you can avoid areas on subsequent coats that got overly dark the first time around.

Be patient and practice on some scraps. It would be helpful, of course, if you could reproduce the current yellowed oak color so you'll be able to see exactly what the new color will look like as you experiment.

As far as "un-yellowing" the color to achieve a gray-blue result, I don't know. Hopefully somebody more experienced with coloring can give you some hints. Otherwise, I guess just play around until you achieve the desired result. Good luck.

Josh

[nailshooter41]

SNIP

A lot of times that kind of furniture is finished with lacquer if it came from a factory, and not with varnish. Two different animals. Regardless, I don't think I would put anything over the old finish and would plan on stripping it off if you are looking for a "tone on" color and finish. No matter what you do, especially if you glaze, you will have the pee yellow color as the base for your new color scheme.

This is problematic, and depends on what your level of acceptance of your finished project will be. If you go over the yellow with a nice blue gray glaze, then you will have the yellow combining with the blues, and it will take on a decidedly green hue. Worse, if the finishes are not compatible, they could do all kinds of things at the time you are wiping your glaze on.

If the project has conversion lacquer or as you say, a varnish top coat, you will have problems staining this. Sanding will not remove the hardened resins (unless you can get it to bare wood everywhere) all over the piece equally and your finish will come out spotty and blotchy. When refinishing, I can tell when I miss a spot or there is buildup of resin because when I spray dye or stain it will make little beads, and that area won't accept color or finish well.

I would strip it (one coat of finish won't be that bad) then tone it the way I wanted and then finish. That way you are sure. Hours and days won't be lost trying to do something that may or may not work. Good luck!

Robert