Official Luthiers Forum!

From the book "Building the American Mandolin, by Johann D. Brentrup

You may do as you wish, but this is my recipe. First I dye the whole instrument with a mix of Trans-Tint yellow and honey amber in a water base. The yellow base and sunburst are applied with a very clean airbrush with the smallest tip. I have never applied any finish before dying the wood as it will only mask the grain. Sunbursts are started at the edge of the top and back by starting to apply a light dye made up of red mahogany, brown maogany and dark brown Trans-Tint mix.





Test the mix on some scrap wood before applying to the instrument. Here is a photo with the first coat of brown applied to the edge. You will have to experiment with distances from brush to surface.
As you apply more coats, the edge will begin to darken and blend more. After 3-4 coats, you can start adding a little more Trans-Tint to the mix and it will start to look like this:



Finally, you can add a couple of drops of black to the mix and only spray around the edges, darken to suit. Keep in mind that the sunburst will always look darker until you apply several coats of your preferred finish. As you perfect your airbrush techniques, you will be able to darken tiny areas where the grain will interfere with





the amount of dye that will be taken into the wood, especially the spruce top.



Here is an example of a very nicely sunburst F5 with the binding being scraped.
Hope this helps...open for questions.

Haans, I am confused by your first post. Are you spraying the very first yellow / amber mixture onto the instrument? If so, is that mixed with finish, or is it just wood dye mixed with alcohol? I've got a pretty good idea what you are doing after that.

Oh....I really like your mandolin shape, too.

Thanks,
Patrick

When you say "water base", are you mixing the Trans-Tint dye with plain water and spaying that?

Great looking sunburst.

James

Lovely, Hans! I'm assuming the colors are all mixed with alcohol. I have found airbrush to work fine on mandolins, but for guitars, its hard to cover enough real estate to make the colors even, so I use a small touch-up gun for that.

How do you prepare the surfaces prior to spraying, do you raise the grain on the spruce with water and then sand back, and if so, what grit sandpaper do you stop at? Do you seal the surface prior to scraping the bindings?

_________________
Rian Gitar og Mandolin

As I said, the "solvent" of the dye is water. There is no alcohol involved, and no finish is on the instrument prior to dying the wood. I spray the yellow as it looks more even on the wood than wiping it on. You can see that as the photos of the V6 show splotches on the top that are actually still wet dye. Nothing wrong with alcohol except it smells. The last photo of the F5 is the first time finish is applied so that while handling the instrument, you don't damage the sunburst. It is scraped after 2 coats of varnish, and then the rest of the finish is applied.
I would believe a touch up gun would work well for guitars, Arnt. The one sunburst I did on a guitar took a long time with an airbrush and I had to hold the guitar at arm's length and use the airbrush at full blast.
Prior to dying, the instrument is sanded through the grits down to 400. I do raise the grain each time I switch to a finer grit.
Here is the finished F5 that was being scraped above.



It is very hard to take photos of an unfinished dye sunburst. As you can see, things look a lot better and color gradiation is better as the finish builds. You can see the grain even in the darkest edges.

Sorry, double post...

Thanks Hans! I like this approach better than wiping stain by hand since the air brush makes it easy to control where and how much is going on. Now I just have to find my air brush.

_________________
Steve Smith
"Music is what feelings sound like"

Thanks for giving us some insight into your process, Haans. Your work never ceases to amaze.

_________________
George :-)

You guys are welcome. I hope it helps...

Haans. IMHO bursts on fresh wood are by far the nicest looking and yours are second to none. Thanks for all your help over the years brother. Like I've said before, just wish you lived a little closer.

Thanks Danny. Wish I lived in Powell River, Canada.