Official Luthiers Forum!

Can I spray a wash coat of shellac tether than brush on?

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Blake Dixon
Kelowna B.C.

me too, for my taste less danger for bleeding out of some woods into purflings etc. I am using this one...like it with a 0,8mm thing...

http://www.sata.com/index.php?id=minijet

Always.
And what Herr said!
Mc

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Mike Collins

Yes, you can spray. For some circumstances, such as sealing a binding channel, I brush. But I spray tops, etc., for an overall sealer/protection coat. Thin it to 1-lb. cut, as previously advised.

I got tired of leveling the overlaps so I now spray and that works sooooooooooooooo much better.
Michael

So why a 1lb cut? I spray a 2lb cut with no problems. Do you just want to put down less material or ??? Just curious.

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Steve Smith
"Music is what feelings sound like"

I use a thicker mix also.
More shellac= less alcohol = less raised grain.

Mc

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Mike Collins

Why the thinner mix?

For me, the answer is simple: I get a smoother coat with a thinner mix. It's almost self-leveling, as long as you don't do anything crazy. I haven't had as good success with shooting a 2-lb cut. Runs, sags, orange peel, and nightmares were all over the place. I am no spraying expert, but I couldn't get rid of the orange peel until I started thinking thin.

Blake, my favorite method for shooting shellac is to mix Zinsser Universal Sanding Sealer (a 2-lb cut) with equal parts acetone and methyl hydrate. If I had ready access to ethanol instead of the methanol, I would use that.

This mix dries super fast, and I have no problems with rosewood right next to maple, and other such (possibly) unruly combinations.

Thanks, I was wondering. My 2# cut is made from blonde shellac flakes dissolved in ethanol (everclear). Don't know if that makes a difference but I have not experienced any of the problems you've noted.

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Steve Smith
"Music is what feelings sound like"

I spray 2 coats of the Zinsser seal coat right as it comes from the can and have no problems with it.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Fred,

What size tip, and what PSI at the gun are you using? That may be all I need to change.

Don't know about Fred but I'm using a Walcom EGO hvlp with 1.2mm tip running at 29psi.

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Steve Smith
"Music is what feelings sound like"

2" Ox hair at 1 pass per second. No clean up required.

I use the Devilbiss HVLP starting line touch up gun with the stock needle size, 1 mm. The air is set at 25psi an the gun.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Spray..................If I brush something always seems to go wrong........!! When spraying Mr. Murphy goes for lunch break.
Tom

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A person who has never made a mistake has never made anything!!!

You don't clean the brush?

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Steve Smith
"Music is what feelings sound like"

Why clean the brush? Just stick the bristle part in a plastic bag with a few drops of alcohol, tied with an elastic band. Keeps it sweet for a couple of days. Quick and fuss free. Pretty much the same with cloth and Danish oil/Tru-Oil - put the cloth in a screw top jar with a few drops of Turps. You can then use the same piece of cloth, less waste with the Tru-Oil continually being absorbed by the cloth.

I can see that. I wrap my good paint brushes with plastic when I take a break while house painting although I always clean them at the end of the day.



That makes sense.

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Steve Smith
"Music is what feelings sound like"

I hate spraying shellac.. I did it for a restoration project that had shellac finish and it doesn't spray nearly as nice as lacquer, since the alcohol dries out before it makes it onto the wood. Also it is a nightmare to clean, since shellac doesn't dissolve quickly like lacquer. Brushing is probably a better idea...

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

There's no real need to clean a brush regularly used for Shellac unless it has become contaminated or you need to switch colour. Storing the brush in a plastic bag simply means that you don't have to wait around for the bristles to soften in the Shellac itself.
The overlaps are only a problem if they are 'heavy'. Very shallow overlaps are easy to rub out. Given that we are referring to a wash coat you shouldn't be getting obvious overlaps anyway. Probably down to technique or the shellac not being dilute enough. You can pre cool the Shellac in the fridge and/or add some retarder if you have trouble brushing. Light coloured inlays need to be sealed prior to using any brushed Shellac. I simply go round with a cloth loaded Shellac as in the Milburn tutorial.

First time I sprayed shellac I had the same problem. Turns out I did not have the gun adjusted properly. Maybe try turning down the air pressure or increasing the material feed.

I use the 3M PPS cup system for my spraygun now and cleanup is simple and very fast.

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Steve Smith
"Music is what feelings sound like"