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I am thinking of doing a sunburst for the first time on a new build, an L-00. I was thinking of only doing the top and I would expect that I would put about 4 coats of EM6000 down first before starting with the color coats. Putting the transtint into shellac sounds good because the coats would dry quickly, but the alcohol in the shellac could interfere with the EM6000. I have heard that you can use EM1000 (which is clear), but some folks report difficulty with it.

Can I add transtint directly into EM6000? (Even if it has a milky color...) Can I add a few drops to the small amount of EM6000 I put in my spray gun?

Any thoughts you may have would be helpful.
Thanks,
Steve

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Absolutely you can, I do it all the time.

I'd recommend putting down a coat or 3 of shellac first to seal the top first. Now spray your color coats directly over the shellac. If you screw up, you only have to sand back down to the shellac to repair (which I've also done). Now go ahead and spray your clear coats.

Feel free to spray the color in your shellac too just make sure it doesn't dry on the way from the gun to the top. All of the alcohol will be gone by the time you spray your finish coats.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

+1

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Dave
Milton, ON

Andy and Dave (or others),
I know I need to practice on scrap and some of this will be revealed... I want it to be a and not a and certainly not a . If I put between 4 - 6 ounces of EM6000 in my spray gun, approximately how many drops of transtint should be put in that 4-6 ounces? ...3, ....5, ...10? (I realize there is some personal preference here, but I'm just looking for some "rules of thumb".)

Also, can I start with shellac as my first coats and then put on some clear EM6000 coats before I start with the color coats? ...with subsequent color coats separated by clear coats?
Thanks again,
Steve

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

I would highly recommend picking up the guitar finishing book and "spraying a burst" or whatever it is from stewmac. I followed the directions in there to make a color panel to figure out exactly what mix I needed to get the colors I wanted.

To get the colors in the burst in the photo above I mixed 3 oz of finish with the following (50 drops is ~ 2.5ml)

Amber: 150 Drops Lemon Yellow with 6 drops red
Red: 150 Drops Red, 100 Drops yellow, 3 drops Black
Black - 150 Drops Black.

Those mixes give a fairly light tint to allow you to make the darkness by spraying more coats. As you get better, you can use stronger mixes and fewer coats.

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Why would you want to do that?

My philosophy is to seal the wood. Spray color on top of shellac. Build clear over that. the closer to the surface the color coats are, the more likely you'll sand through.

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

There are two aspects to the mix...the blend & the intensity. As in the sunburst tape Andy mentioned, I get the blend by doing samples mixes in an ounce of lacquer..... so many drops of this/that/the other in an ounce to get the COLOUR I want. Intensity is set by taking a multiple of that blend to get the covering power. (eg 3 drops tobacco/2 red mahog/ 2 amber per oz. might give me the perfect colour, but I bump it to 9T/6 RM/6A per oz to get the intensity & use that formula in the gun)
If masking bindings, there is some merit in shooting some clear first, to seal the tape & prevent colour bleeding under it. Your choice.

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Dave
Milton, ON

That is great information and just what I was looking for. Thanks Guys. I do have the Stew Mac book, but it's nice to bounce these thing off folks that have done it.

Andy - You said -

That's why I suggested to follow an intial coat of shellac with a few coats of EM6000 before applying the color coats...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

The approach that works for me is to add enough tint so that you approximate the depth of color you are looking for in one pass...on a test panel. That becomes a reference. Then I use essentially the Andy plan. If the plan is to spray 12 topcoats coats, for instance, divide the number of drops of tint per ounce that you used in your reference panel by 6 (or 1/2 of the total number of topcoats) and then mix up that diluted ratio. The idea is to get to your referenced color by building up successive diluted coats. It's MUCH harder to get even color coverage in just a pass or two.

If the color appears about right after four or five coats, stop with the tint coasts and lay the rest of the coats down clear. If the color doesn't appear deep enough after six coats you have some latitude do more color coats before laying down the clear. But definitely have a number of clear coats over the color. 12 is an arbitrary number of coats.

Let some other guy that uses EM6000 tell you how many coats to lay down. I use 8 coats of solvent based nitro on my electrics. I try to get my color down in 5 or 6 passes.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

FWIW I usually end up at about 20 coats with EM6000 and, if tinting lacquer, certainly try to get that done in the first third.

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Dave
Milton, ON

I still don't get it. The more coats under the color, the closer to the surface you move the color hence making it easier to sand through.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I wonder if the confusion might be about whether the "surface" refers the surface of the wood versus the surface of the finish.

Yes, there apparently was some confusion on my part...

But basically, I was thinking that I should shoot some shellac first - followed by a coat or two of EM6000 before I begin color coats (transtint in EM6000). By spraying a few coats first, I can sand the color back without going back to the wood, if I don't like how the color came out.

After I'm satisfied with the color coats - follow with enough coats of clear EM6000 to get a level surface without wet sanding through the color coats - maybe about 12 - 18? Then buff...

I guess I want the concentration of transtint "strong enough" to not have to apply too many color coats - but "weak enough" to be able to control the amount of color going on. That's why I was looking for a ball park amount of transtint to use...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

I was more worried about sand through of color when leveling at the end.

I guess when you think about it, 2 coats of finish is going to be super duper thin so I guess it wouldn't be a problem. If this is your first burst, I would go for a lighter mix. Much easier to do a good job.

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

All the TransTint colors are different in terms of the workable ratio. For instance...using 2 drops of amber of red per 10 grams of nitro allows me to lay down a nice, even color with about six coats. However, using that same ratio with blue is way too dark for my tastes. Therefore, I have have to use test panels to determine a good ratio when using a new color.

On that same note I wouldn't make the assumption that the proper ratios you establish for Transtint colors would apply to any other brand of tints....or that the above ratio would apply to EM6000.

_________________
I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic