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I'm trying the O'Brien method of sunburst spraying dye in shellac. What I got was a real grainy finish much of which sanded off like a coarse dust. Some of the dye did stay behind but most of it came off with light sanding. Should I be spraying more material? Should it look wet when I spray? I'm tempted to skip the shellac and go straight to dye in lacquer.

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Rich Smith
Issaquah, WA

I'm not familar with Robbie's method.....but I use shellac 'bursts under my Varnish finishes. I spray the colors fairly wet, and only sand lightly. For 'bursts with Lacquer I just tint the lacquer.

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I find it much easier to just use alcohol rather than shellac, which can cause the 'pebbly' thing you're talking about.

Also, you shouldn't be sanding the color coats, they are ultra-thin, or should be.

My system is.
A: fairly wet clear coat
B: Shaders (sometimes with thin clear coats between, but not always. Depends on how confident you are)
C: Finish the clear coats.

I only have one burst under my belt, but it came out pretty nice, I just used shellac but very thinned down, therefore it sprays wet because it is mostly alcohol. I did not sand at all, sprayed the clear over it and sanded very gently so as not to go through.

If you used flake shellac, it needs extra filtering, but graveley seems to be how shellac sprays.
Rob

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I'm using 1 lb cut shellac flakes. I think I'll try the alcohol method perhaps with a bit of shellac. Mahalo

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Rich Smith
Issaquah, WA

Typically I will put the color right in the first couple coats of finish and go to clear over that before I do any sanding. Any time you sand the color you mess up your burst. Avoid sanding the color which means don't wait too long to apply the clear over the color. Also another tip, use intense color so you can use very little of it.

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Don't sand the color coat; wait until you get a couple coats of clear on it first.

Does anyone spray water based dyes as per Stew Macs finishing book? Dan Erlewine seems to recommend this the most as sand throughs can be touched up the easiest with these dyes according to his statements in the book. He also states that this allows the grain to show through more as opposed to other methods. I haven't tried this but would like to hear from any who do theirs this way.

Yes, I do and it works pretty well. I've dune bursts with the dye in shellac and also with the dye in WB lac and prefer it in the lacquer. I typically seal with shellac, build the burst very gradually with a mild color and put on more coats to get it darker. It's much easier to control that way.

If you check my blog in my sig, you'll find a couple pics of my bursts.

P.s. I've tried spraying dye in water alone on bare wood and It was a disaster - super splotchy, found a few pores that I didn't know were there. Finish can also run. I'll never be spraying a color without some sort of finish as a binder so to speak.

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As John mentions, the best way is to have as much colour in the mix to avoid too thick a finish. It requires good spray technique and the right equipment, though. The other part is to spray a coat of clear after each colour. First it "seals" the colour and prevents catastrophic sand through, second it seems to blend the colours much better, at least with shellac.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Ricardo, that sandy finish that sands off sounds a lot like you had too much air pressure coming out of the gun and the finish was drying before it got to the guitar.

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Laurent, beautiful sunburst jobs. Thanks all for the tips.

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Rich Smith
Issaquah, WA

I like to spray a medium strength dye solution in 1 part nitro lacquer to about 4 or 5 parts lacquer thinner. The nitro is the binder and the extra thinner keeps color coats thin which is the key to not having to sand them. It also keeps binding scraping to a minimum.

Here is a link to Fine Woodworking's video on doing a burst, by James Condino http://www.finewoodworking.com/Materials/MaterialsArticle.aspx?id=30136 .

Bob

I've always sprayed color dye with alcohol and a little nitro for binder like maybe a capful of nitro to 10 oz. of dye solution.
This is over the flat sanded base coats of clear lacquer.
I must be in the minority as I don't hear of anyone doing it this way.
Do you guys spraying color with nitro have any issues with a ridge when masking or scraping the binding? I realize that you try to keep the nitro coloro coats as thin as possible.
Nelson

It's hard to do a dark burst without a ridge. I've discovered that there is a stage in the hardening about 10 minutes after spraying when you can burnish the ridge down with a fingernail. You can also mess it up doing this if the burnisher grabs.

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Howard Klepper
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When all else fails, clean the shop.

Bob, the video shows applying water-based dye with a pad. Could I apply alcohol based dye the same way - similar to french polish?

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A higher purpose for wood.
Rich Smith
Issaquah, WA

As a relative beginner compared to Laurent, I have to disagree with this strategy for a beginner at bursts. Getting a burst to come out well is a developed skill. The more color in the mix, the less room for error. One errant twitch or a slow down in the hand and you have a big mistake to fix.

Start with a weak color mix and gradually make it stronger as you get better at your gun handling. Mark Swanson gave me that advice when I started doing bursts and while my bursts aren't quite as nice as Laurent's, they're pretty darn good and getting better.

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Andy, I hear your argument. However, spraying multiple "weak" colour coats will build a very thick finish, especially with a dark burst. Not only do you have to build up clear finish on the outside purfling, binding and rosette lines on the top, but you may have to deal with too much shrinkage, and worse, various rates of shrinkage. It is perhaps less an issue for an "all-nitro" finish (burst and clear coats), but it can morph into a nice mess if the burst and clear coats have different shrinkage rates. I use shellac for the bursts and oil varnish for clear, I can assure anybody that shellac shrinks a lot more, faster and for a longer time than any oil varnish. And I won't mention the negative effect a thick finish has on tone (IMHO of course).

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

My technique uses as intense color as I can mix but spraying very lightly so the color builds slowly. This allows great control (and room for error) over the spray. I don't use any thinners but that sounds like it may be worth checking out.

Laurent - I indeed mix my color in with my lacquer (acrylic WB in my case). I do also get a ridge at my binding though too. I will have to try upping my color concentration for my next burst but I'm still not going to go too crazy. In my case, I only burst the back and sides, not the top so I'm less worried on how it may affect the top.

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The best way to do a sunburst is to airbrush it with alcohol or water and Trans-tint directly on the wood. Finish goes on after.

Laurent and Haans;

Great looking bursts!
Howard is correct about burnishing the ridge that the tape creates too... great advise!
regards,
jack

I did one recently as Haans describes & I don't think you can beat this approach for depth.

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Dave
Milton, ON

Nice stuff guys..!

Trev

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