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colorao39
08-26-2009, 02:06 PM
this violin finish type used by Eastman for archtops, is available from Behlen or Stewart Mac.

Will it go onto a water based grain filler?

Brackett Instruments
08-26-2009, 02:31 PM
That particular Sprit varnish is basically colored shellac. It will work with the waterbased grain filler. I don't use sprit varnish or waterbased filler, but again it will work. What kind of wood are you filling?

george wilson
08-26-2009, 08:29 PM
Shellac is a very cheap type of finish. It does not stand up to sweat or moisture well. I have used it on a few flamenco guitars where I wanted a very thin french polished finish,and it can be traditional,but that was a special category of use,where the guitar is used more in a concert situation,where it is not exposed to abuse.

colorao39
08-29-2009, 02:28 AM
george wilson,

thanks for the info, a long sleeved shirt sounds like a good idea, and this would not be for small club dates.

colorao39
08-29-2009, 02:42 AM
That particular Sprit varnish is basically colored shellac. It will work with the waterbased grain filler. I don't use sprit varnish or waterbased filler, but again it will work. What kind of wood are you filling?

This guitar top is African mahogany, maker applied red shellac and unspecified lacquer, dimples cover entirely. Spirit base sounds good for ease to apply, and wonder whether brush on shellac sanding sealer from Zinsser, plus spirit ground varnish ($20 for 100 ml) and repeated coats of violin varnish, might fill the dimples without filler.

Does ground varnish go on diluted? How many bottles for a dreadnought top?

Laurent Brondel
08-29-2009, 07:35 AM
The Violin Varnish from Behlen is a spirit varnish, meaning de-waxed shellac + resin and gum (I forgot which ones specifically). One bottle is more than enough for 2 guitars at least. It's great as a sealer actually, but as a finish it doesn't dry too fast, remains soft for a long time and then cures to a flaky kind of feel. What's in the bottle is very high in solids, I mix it at least 50/50 with denatured alcohol. Brushing can work, but is not the ideal method for this, either padding or spraying would be ideal.
I wouldn't expect any finish to fill imperfections on a surface. You'll have to level the existing finish as flat as you can by wet sanding (or entirely remove it).

george wilson
08-29-2009, 08:18 AM
colorao,Laurent has given good advice.

Howard Klepper
08-29-2009, 08:51 AM
Shellac is a very cheap type of finish. It does not stand up to sweat or moisture well. I have used it on a few flamenco guitars where I wanted a very thin french polished finish,and it can be traditional,but that was a special category of use,where the guitar is used more in a concert situation,where it is not exposed to abuse.

Object to calling a shellac finish "cheap," which implies both inexpensive and of poor quality. True it does not wear well (at least until 50+ years of crosslinking have toughened it). But done well it is among the most beautiful of finishes, the most acoustically transparent, and in terms of longevity does not break down chemically after hundreds of years.

On another thread people have been extolling the benefit of tough, hard finishes that are impervious to whatever drinks or other objects may be thrown at them. If that is what you plan to subject your guitar to, go for it. I don't think a guitar needs to be protected as if it were going into service as a bar top or gym floor.

And hi, George. Beautiful work!

george wilson
08-29-2009, 09:16 AM
Howard.You probably didn't see another posting where I mentioned that I French polished a flamenco guitar I made for my own use. I put a VERY thin finish on it. It sounds great(but that's not just the finish).

I would not want to do that for a guitar I would sell,because it would be coming back for warranty work.

Shellac is truly a cheap finish. It is insect secretions. It does not retain a high polish like varnish will. It goes dull over a period of time. Sweat messes it up as does water. We made a spinet harpsichord on film,and a violin,in Williamsburg in 1974. We were under the gun as a whole film crew was standing around waiting for the next shot to be readied. We put a very beautiful glossy shellac finish on the spinet because of time constraints. Even a few years later,that finish was dull looking. We used super blonde shellac.

There is even a 17th.C. treatise from England,which talks about how untrustworthy shellac is,and that it loses its shine. This has been known from way back.

My guitar is not very shiny,but I play it because it sounds good. Others might not like its looks.

There is one type of shellac that does stand up . That is Siam seedlac. It comes in a pure,unmessed with form,full of chunks of foreign matter and crud. You dissolve it in a bottle,and carefully take it off the top without disturbing the sediment.

I think that in the processed shellacs,something must get lost by evaporation,or whatever,because this crude shellac does hold a polish. I've french polished things with it in the 80's that are still like new.

It has a orangeish brown color rather like the tops of Ramirez classical guitars(he doesn't use Siam seedlac). However it stays just as polished as the day you put it on. If you don't mind the color,it is good. Keep water off it,too.

I don't advocate hard,thick finishes. I seal the wood very perfectly and get by with a few coats that look like 20. Thick finishes do kill sound,most people know that. Factories tend to use finishes like that to attract sales. The old Goya guitars of the and 60's big selling point was that thick,glossy finish they had over a fairly cheaply made instrument. They sold lots of guitars that way to those who didn't know better.

Don't think that if you are going to sell guitars to other people,you won't hear about it if the finish doesn't stand up. Back in the 60's,I sold a guy about 5 of my guitars one year. An individual. This was down in the hills of North Carolina,where country stores still had potbelly wood stoves. He brought back a jumbo guitar with the lacquer on the neck bubbled up. THE SAME LACQUER MARTIN WAS USING at the time. I know perfectly good and well that he leaned the guitar up too close against a wood stove. At that time,I was trying to make a living building guitars,and he was my best customer. He denied it,and I was forced to refinish the neck for good will. That's the kind of crap you can expect over finishes,believe me!!! Along with all the other crap,misinformation,and superstition too!! Making guitars can be a real pain in the neck when you deal with some people.

I had another person crack his guitar,about a month old to pieces,by leaning it against a steam radiator in his room! I had made it as a gift to him.