Achieving a 3-D Effect with Curly Maple

Comments on enhancing grain figure and chatoyance. December 27, 2006

I am working with an exotic wood for the first time (curly maple), and I am going to be doing a high gloss finish for the client. I know how to get a spectacular high gloss, but I need to know how to get that 3D effect I see so often. Will it come naturally with a high quality high gloss job, or does the wood need to be treated/prepped prior to topcoat?

Forum Responses
(Finishing Forum)
From contributor A:
Are you staining or just a clear finish? If it's just a clear finish, you should pop the grain with some shellac first.

From contributor T:
Search the WOODWEB Knowledge Base on "chatoyance" and you'll find a large variety of opinions on how to enhance it. My own preference is to use amber shellac or a shellac or lacquer that has been dyed with a light transparent dye. Just a little bit of transparent color in a wash coat will make a big difference. I personally do not use pigmented stains to enhance chatoyance because I feel the opaque pigments tend to hide or mute it rather than enhance it, but not everyone agrees with me on that.

From contributor D:
Try adding a "pearl essence" to your lacquer. Your supplier should be able to help!

From contributor B:
Here's an article from Jeff Jewitt that addresses the specific issue you have. This approach works very well.

Start with the right stain - Pigment-based stains, which are made of fine, colored powders suspended in a medium, don't bring out the best in curly maple. For that reason, I prefer to use the more transparent water-soluble dye stains, which are user-friendly. Dye stains can be used one of two ways. In diluted form, they highlight the curl a bit, making it just a tad darker. And used in a stronger solution, they color the wood and accentuate the curl even more.

Darken the curl and raise the grain - To slightly darken and accentuate the curl, apply a diluted brown dye stain as the first step. I dilute it eight times the recommended concentration, or until it's the color of strong tea. After sanding the wood through 150-grit paper, lay on this dye as a grain-raising step. Wipe or spray it quickly all over the wood as evenly as you can, then let it dry. Sand the raised grain with 180-grit paper. Sanding will remove almost all of the dye color from the surface that has no curl, but some of the color will remain in the curl figure. This is exactly what you want. If you like the color of the wood, leave it this way and move directly to applying an oil sealer. But if you want to add more color, follow this step with a darker coat of dye stain.

Add color and highlight the curl even more - If you decide that you want more color, apply the dye stain you've chosen at its full strength. Wipe or spray it on evenly and then - while the surface of the wood is still wet - wet-sand the dye into the wood with a maroon Scotch-Brite pad. (Don't use steel wool, iron cause black stains that will ruin the finish.) The Scotch-Brite will de-nib any additional grain raising that occurs. Let the wood dry at least overnight.

Seal the wood with a liberal coat of oil - Sealing the wood with oil adds real depth and some luster to the surface of the wood. I prefer to use boiled linseed oil, but you can use just about any oil finish you prefer. Flood the oil all over the surface of the wood and add more oil to the figured areas as they absorb each coat you lay on. Keep checking the wood every 15 minutes or so, adding oil when necessary. When you reach a point where the wood won't drink in any more oil, take a break and let the oil set for an hour or so. Wipe the excess off and let the wood dry overnight.

The next day, spread a light coat of oil over the surface and wet-sand lightly with 400-grit wet-or-dry paper. Don't sand too vigorously - especially on the edges - or you risk cutting through the dye. (If you do go through, mix some alcohol in the dye and dab some on the areas that need touch-up.) Put the work piece aside and let the second coat of oil dry for a couple of days before moving on to finish coats. Topcoat with the film finish of your choice.

From the original questioner:
Thanks for the responses! I have so many questions, but I will try to hit the important ones first. Given the regimen in the above article (a light dye to achieve contrast, followed by liberal coats of linseed), what would be the best type of topcoat product to achieve a crystal clear, ultra high gloss finish that will sit well given the large amounts of linseed oil? Also, would pore filler be necessary prior to staining?

From contributor T:
If you want crystal clear, gloss CAB or pre-cat lacquer. Just be sure you let that oil dry for a while before you finish it. No filler (it's opaque). If you need to fill, use your top coat material, a sanding sealer or a vinyl sealer.

There are lots of things that cause figure in wood. The 3D effect or chatoyance is one of them. It results from light reflected by cell structures that intersect the surface at various angles. As you turn or roll the board, the angles change, the reflected light changes, and it looks like the board has come to life. You want to preserve the visibility or reflectivity of those cell surfaces, so you want to use a very transparent finish and keep in mind that lighter colors are more transparent than darker colors.

I'm not here to say anyone's approach won't work. But I would strongly urge you to make up some samples and try a few different techniques. Try the dye and oil, but try some amber shellac and some lightly dyed lacquer as well. The latter two will color and seal your wood in one step and be ready for topcoat in an hour. The first will take a week or two.

I recently did a test to illustrate how different finishes affect the way the color of cherry changes with UV light and time. I didn't test shellac or NC lacquer, but the piece that was finished with plain old water white CAB lacquer happened to have some chatoyance in it and just the lacquer did a very nice job of bringing it out.

Consider all of the recommendations and then make up a few samples. You'll get much better results with less time and less money, plus you'll have your own opinions about which works best!