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I recently completed my first french polish on a guitar that I was planning on keeping for myself.... love the guitar and it has some experimental stuff in and on it.

The problem is that there seems to be some sort of reaction with the lining of my case and the FP. Twice now it has left nasty looking spots on the finish (almost like it dissolved the shellac) when I put it in the case. The first time I thought maybe I didnt let it gas off for long enough and fixed the belmishes. I have let it hang in the living room for almost a month now and took it out for a day and when I pulled it out of the case, anywhere the case lining was touching the guitar has this "melted" look to it.

This is Stewmac's ultra blonde shellac and I used the solvent that they sell to dissolve it (Behkol). I am quickly loosing my love affair with FP guitars.

Is this common with FP guitars? Is it just something in the case lining? Help!

 

_________________
Reguards,

Ken H

Maybe its a case of experimenting.
I've tried a few different brands, types of shellac, ingredients, and cut weights.
Some types of shellac i prefer to others.

I get a good result from using Saligna shellac flakes Blonde.
Avaliable from:
Timbecon

Completely Denatured Alcohol is what my French polishing text recomends.
I use Methylated spirits, or white spirit and that works.
My french polishing text also recomends Mineral oil as a lubricant.
I've tried linseed oil and mineral oil and decided that mineral oil is easier for me as a rank amatuer to work and get a nice shine on spruce.
So thats my preference.
Linseed oil actually becomes part of the finish, where as mineral oil pretty much wipes off.

The other tip is to not do more than two coats in a day, and then let it cure for 24 hours before applying more coats.

Some luthiers complain that lighter coloured shellacs are softer than darker ones.
One of the specific complaints I read was one person (other than yourself) complaining of a guitar with super blonde type shellac leaving an imprint on the guitar from the case lining.

Cheers,
Claire

More likely, the culprit is the case and not the finish. The lining material in
the case may well be some sort of synthetic that is still gassing off some
organic compound used in its manufacture. I have seen plastic straps eat
into lacquer finishes as well. Try leaving the case empty and open for a
couple of weeks or more. Just a thought.
Craig S.

That's probably a good idea.  Like carpet, synthetics do emit fumes that could be damaging to some finishes.  The glue used to attach the material could also be the culprit.  You might even contact the maker - maybe they don't know.  Or might issue a warning with their cases that they could be damaging to certain finishes.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

[QUOTE=Hesh1956] I agree with Waddy that the case is more suspect. What brand case is it?

I "had" one case, from Guitar Center...., that stunk so very bad I nearly threw up when ever I opened it....... I tried things to get rid of the smell like leaving it open in the garage for months but it still stunk when it had been closed.

In the end I threw it out because it stunk so bad....... [/QUOTE]

HaHa... I have that same case. I've had it for about four years and I also left in the garage for months, open in 110 degree heat hoping it would solve the problem...

I still have it. It still stinks.

I too would suspect the case. What's the brand?

This is a Guardian case. One of their top of the line cases. 

Thanks for the replies... I'll leave the case open for a while aqnd see what happens... Hadnt even thought about the case gassing off.

 

Hesh, It was probably the oak the case was made out of that stunk. I have sawed oak logs (I own a portable sawmill as well) and some of the oak logs smelled just like somebody puked in the log. The smell goes away after it dries out, bet any time you saw it the sawdust smells just like puke.

_________________
Reguards,

Ken H

Claire,

Thanks for trhe tip on the shellac and finishing source! This guitar had shellac on it for a couple of months and had been completely finished for well over a month... maybe like 6 weeks. The finish was so hard that even alcohol had a hard time dissolving the finish.

_________________
Reguards,

Ken H

I think some of those glues, used for gluing foam and fabrics, contain formaldehyde.  That would account for the sickening smell.  It could also be the foam used for padding.  Some of them also contain formaldehyde.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Bingo

99% of the time that this happens is caused by the foam underpayment under the plush or crushed velvet lining is still gassing off. This also has to do with what type of foam is used. This one reason to stick with a well known case manufacturer.

Underlayment not underpayment this one my spell checker screwed up

[QUOTE=MichaelP]Underlayment not underpayment this one my spell checker screwed up [/QUOTE]

That's what you get for using BIG words that spell checker doesn't know.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

This is a timely post. Just this weekend my nephew showed me the guitar I finished for him last month. It has case fuzz stuck to the finish on the left lower side and top. This case stinks too. It's a TKL and it smells like a tomcat has been living in it, including marking its territory.

Now I've got to refinish, unless someone has a magic solution...

Bruce:

What was your finish?

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

You can't even tell by the manufacturer. I bought three TKL cases a couple of years ago. The two SJ cases were fine but the Dred case smelled terrible even after months of being left open.

                      Paul

Paul. not to knock TLK cases at all because they are good cases but they make so many grades of cases that it would be likley that some less than top grade materials were on ocasion used in the top line cases. This is likly what happened with you. This issue and a few other small ones is the reason I finally went to Ameritage cases on all my guitars.

Does your nephew have a cat? Reason I ask is foam smells more like polyethylene while curing than cat urine. Now the uretha and ammonia in cat urine would most certainly cause a problem with any finish

French polish finish, olive oil for the lube and 190 proof grain spirits.

He's a college student and doesn't have a cat. He bought the case new at a Guitar Center (I think) and it was kept closed and unused until I delivered the guitar to him.

[QUOTE=BruceH]French polish finish, olive oil for the lube and 190 proof grain spirits.

[/QUOTE]

This is why I am wondering if it is the french polish....

_________________
Reguards,

Ken H

I would doubt it was because it was French polished. Now it is possible that the FP finish reacted to the off-gasses faster than nitro would have. but that is like blaming the car in the right lane for not geting out of the way of the car in the wrong lane