Iridescent Finishes

Some woods show natural iridescence, especially if sawn the right way. But you can also get an iridescent look using various specialty finish coatings. February 23, 2008

Is it possible to achieve an iridescent finish on a project - something that appears to change colors depending on the lighting?

Forum Responses
(Finishing Forum)
From contributor P:
If you use a wood that is very lustrous, such as a nice mahogany, and a finish that doesn't cloud the sides of the wood cells, it's easy. If you use a wood such as pine and cover it with all sorts of wood fillers and satin urethane, it's not so easy.

From contributor T:
It is easier to achieve iridescence with figured grain, burl, or quarter-sawn, but it's possible to get a little bit with any wood. I often spray a wet coat of diluted dye (reddish, orange or yellow), left by itself or shortly followed with a wiping stain, seal and sand, then glaze with a dark green, like Van Dyke brown, seal and sand, then tone with a reddish brown and topcoat. The three or four layers of color will just look brown when lit and viewed from the front, but will change colors as the lighting and angle of sight change.

From contributor C:
I have done this using acrylic artist's interference colors (on small scale projects). I have intermixed two or more such colors with brush strokes to do the job. Golden's colors are top grade and come in many size containers, though last time I checked, they didn't have all the colors that I have from Liquitex. Texture seems helpful, and pay attention to the direction and strength of your brush strokes. I have never equaled the color qualities of the feathers on some of my fowl, but I have created some interesting finishes. Automotive specialty houses have created holographic glitter powdered additives and many other high-tech additives to achieve this kind of look and many of them are intriguing... but you'd better have some change in your wallet when you go to get you some!

From contributor R:
I'm not sure what project you have in mind since you didn't mention it, but I have worked with powdered pearls available from an auto body paint shop. Did a kitchen... rift white oak, very straight grain, dyed black, real black. I incorporated some blue pearl powders into the top coat. Solid maple crown and base painted red and no pearls in the topcoat.
Lots of movement and shimmering.

From the original questioner:
Thanks to everyone for responding. Contributor R, when using the techniques that you mentioned, did you dilute any of the colors and did much of the grain of the oak show or did it appear more like you had painted it?

From contributor R:
This was a water based dye stain and not a painted type finish. Rift white oak shows a grain, kind of like a 1/4 sawn oak (the flake), that did show through. The pores of the wood were not filled, but because I flat sanded the coats, the pores had a sharp - not rounded over - look to them. As far as thinning, I just used water for the dye, and since I wanted the sharp look to the pores, I did thin the sealer coats and the top coats. I mixed the pearl into the final topcoat and it seemed that every minute or so I was agitating the mixture to keep it constantly mixed. On a side note, while I was making my different in house samples, I wasn't getting the exact look the control sample was showing me. Turns out that by keeping the coating agitated, the pearl didn't have a chance to settle. That was what helped me get a consistent look. Another side note... I lost my booty on this finish but I learned an unlimited amount of money's worth of knowledge from this venture.

From contributor D:
Are you painting the project? If so, Chrome Illusion by Dupont will get the job done, but at $500 a quart it's a little high. Painted a golf cart with this stuff and it's a mindblower.

From contributor G:
I've seen cars that look different colors depending on which direction you are looking from. I think that is what contributor D is referring to. You can also do some trickery with the gun and reduction of the colors, but that would be difficult on any large project. What exactly are you trying to do?

From the original questioner:
The project would be a bookcase. This thread actually stemmed from a discussion at work. It started with how different finishes would look in black light and it evolved into the iridescent thing.

From contributor I:
I sprayed an MDF bar cabinet with Chrome Illusion this year and it turned out fantastic. I used brushed aluminum laminate insert panels. It is expensive but there is only one way to get that look.