Luthier Tips du Jour Mailbag - Sunburst Finishes

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In this video, Robbie O'Brien answers a viewer's question about colors in finishes. He then demonstrates how to do a sunburst finish on an electric guitar.

Video Transcription

[on-screen text reads: Luthier Tips du Jour Mailbag]

Mailbag question: What order should I apply the products when finishing a guitar?

Robert O'Brien: Today's Tips du Jour mailbag question comes from Chile. "Dear Robert, I want to finish a Les Paul guitar, but I don't know which order to apply the products. Should I apply the dye, then the sealer, then lacquer? Also, is it even necessary to apply a sealer? Thanks for your response. Ignacio in Chile."

[on-screen text reads: www.obrienguitars.com]

Finish application sequencing for a color coat

Well, Ignacio adding color to your guitar can sometimes seem intimidating, but it doesn't have to be. It's actually quite easy. A color coat can be quite simple, like an opaque, solid color on the guitar. It can also be quite detailed and ornate like a sunburst finish. When I do an opaque color, what I like to do is first sand the guitar up to the appropriate grit, usually 220 or 320, and then apply a sealer. I then apply color to the top coat. That way it's reversible. If you don't like the results, you can sand it back to the seal coat without having to sand back to the wood.

Finish application sequencing for a sunburst-type finish

For a sunburst-type finish where I want to pop the grain and accentuate the grain and show it off, I start by painting the guitar with a black dye. This dye could be alcohol-soluble or water-soluble. Now, the difference is that the alcohol flashes off quickly. Therefore, the dye doesn't penetrate as deeply into the wood. A water-soluble dye, it will penetrate deeper into the wood. Once I've painted the surface with the black dye, I let it dry and then I sand it. I don't sand it all the way off because it goes pretty deep into the wood, especially if you use the water-based dye, I just want to pop the grain or accentuate the grain. Next, I apply a vinyl sealer. Now, this helps seal in any contaminants. It's also a leveling agent that's easily sandable. However, if you want to apply your color coats directly on the wood, you can. Be careful though. If you don't like the results, you have to sand it all the way off, and that means sanding the wood.

Usually what I do is I add the color to the lacquer, if I'm using lacquer, sometimes I use other products, but if I'm using lacquer, I add the dye to the lacquer and then I dilute it about 50%. That way I get a very, very thin color coat, and the lacquer serves as a binding agent. And I spray the guitar. Be careful because the more you spray, the darker things get. If I'm doing a sunburst-type finish where I want things darker around the perimeter, I spray more in those areas or I add more dye to the mix, so it's more concentrated. I dial down the width of the fan on my spray gun so that I'm just hitting around the edges. After a very light sanding, being very careful not to go through your color coat, I then add the clear top coats.

How many top coats you apply depends on you. I usually spray three to four coats, let it sit, level it, and then spray another three to four coats. But you want to make sure you get enough on there that you can level and buff afterwards without going into your color coats. After appropriate cure time, leveling and buffing, the results could be quite stunning, and it's really not a lot of work. It's not that difficult to do. Now, here's a good rule of thumb. Always test on scrap before you try this on your guitar. That's important. So Ignacio in Chile, I hope this has answered your question and I look forward to receiving pictures of your guitar. Happy finishing.

[on-screen text reads: More Luthier Tips and online courses available at www.obrienguitars.com]

StewMac

 

Robbie O'Brien

Luthier and Instructor, Lutherie Academy