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I let the wrong guy play my new guitars last week. He wasn't rough with them nor did he do anything that any other guitarist wouldn't do. He did, however, disolve the finish off of the necks. The necks were french polished. When I returned home I noticed that the necks were dull and feeling rough in spots. I took a rag to wipe off the finger prints and promplty wiped off the finish.

I've heard about guys like this but I've never met one before. This didn't happen with other players who played the guitars before that. It's possible that my finish was too thin or had some other flaw but the effect this guy had on the finsih was so dramatic that I'm inclined to blame him. I'm not going to mention it to him because he can't help his body chemistry and the problem might not manifest itself on a lacquer finish. He might not even know that he can have this effect. I wonder if there is a diet issue?
Mike Mahar38622.4334490741

How cured was the finish? More than 30 days? If so I would suspect contamination of some sort, like a solvent o his hands. I am one of those that can play Phos. broz stings for a half hour and they will turn jet black every where I touched them. but I have yet to fine some one's ph level that would harm a cured finish

The finish was over 30 days old but not by much. Shellac is alcohol based. He was pretty sweaty when he played it. I'm not sure where he would have picked up a solvent, however. My current thinking is that the finish was a lot thinner than I thought it was. I might have been seconds from buffing through. I tried a new approach to my french polish where it touched it up on the buffer.

Many years ago, I owned a Goya dreadnaught. Made in Sweden -- spruce top, pearwood back and sides. I dunno what kind of finish it had, but I let a friend's brother play it once, and after a couple of hours of playing it, he had killed the strings and removed a big patch of finish on the soundboard along the top of the lower bout, and the side, and the back. That finish had definitely cured for more than 30 days before he got ahold of it. Some folks are just like that.

Best,

Michael

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Live to Play, Play to Live

Wow and I thought I was bad

Mike,

I've got a bouzouki that I want to strip the finish from. can I borrow your friend for a day or two?

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

If it had been summer I would have suspected that he had bug repellent (DEET) on. It is well known that DEET disolves almost all finishes. Talk to a builder who specializes in BlueGrass. They play at a lot of outdoor festivals and bug spray is a big problem.

Many if not most fine classical guitars are french polished. Because of this and because sweat tends to dissolve the shellac finish, many if not most classical players use a sock for their right arm when playing with short sleeves. Winter-weight knee-socks seem to work best. Cut the foot out, and slip the rest over your arm. This will keep sweat off the guitar.

Now, as for those whose hands sweat a lot, about all I can recommend is they have a towel handy that they can use frequently to wipe their hands on.

Best,

Michael

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Live to Play, Play to Live

Ok my hands don't sweat much at all but I can oxidze a set of strings in two min from a mile away. That is why I play on Elixir's NanowebsMichaelP38622.6564236111

AT the 2003 ASIA conference the guy from Target coatings was there talking about water based finishes. The discussion included talk about caustic sweat. The Target guy said that human sweat is one of the most complex chemicals with which a finish will ever come into contact. He also mentioned that there was a large difference in the composition between people.

Mike, I find french polish is extremely difficult to buff through with a machine buffer.

I'd blame chemistry. Time shouldn't be an issue, and thinness of the finish doesn't sound like the matter either.

As for diet, I usually recommend the south beach diet with daily exercize for anyone buying one of mine. Not to mention washed and dried hands.

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French polish. Alcohol. Had the fellow been drinking quite a lot?

[QUOTE=npalen] French polish. Alcohol. Had the fellow been drinking quite a lot? [/QUOTE]

Not that I could tell. I can generally smell Alcohol when it is around. I pretty sure that sweat was a major factor. This was my son's fencing instructor and we were looking at the guitars during a break.

Did he use alcohol to clean the strings?

Maybe he had some kind of alcohol based cleaner on his hands when he was playing it. Maybe aftershave. Lots of things have alcohol in them.

If he uses after shave or deodorant both are usually alcohol based as is almost anything with perfume. Some of the nicest handrails I have layed a hand on were ones in very old buildings that have never been re-finished....I think there is a point in there somewhere!!??

Shane

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Canada

I guess we'll never know for sure. I do have to put a few more coats of finish on. That is a nice thing about french polish. You can fix it.

THEY'RE ALIENS

[QUOTE] This was my son's fencing instructor and we were looking at the guitars during a break.
[/QUOTE]

Mike you're not supposed to "fence" with a guitar!

On A Serious note...I F.P. all my guitars and for what it's worth...If that Shellac wasn't realy cured...sweaty hands would affect the finish. Ever put a drop of water into fresh shellac? But it should also be no more than a 10-20 minute repair.

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"