Official Luthiers Forum!

Hi!
So, I have about 10 guitars (from newer Martins to vintage Martins and other assorted guitars) that I was storing on stands in an unfinished attic that has exposed spray foam insulation. It seems after about 5 months of being there - they have all developed a thin and sticky residue which I believe is off-gasses from the spray foam. It's yellow/orange when I wipe it off, like a polyurethane . I've been scrubbing it w/ mild soap and water, babywipes, and anything else I can think of, but I can't seem to fully remove it and the guitars don't polish like they used to.

Can anyone recommend a good deep cleaner that might help this nasty situation?

Thanks much.

I'd say that you have a very expensive problem and need to learn how to care for your instruments. The hindsight solution is of course, throw away the stands and keep the instruments in the cases...humidified. You might also consider what that spray foam insulation off-gassing is doing to your lungs...

I'd try Naptha on a small not so visible area. I fear you may have to carefully scrape the residue away with razor blades - very carefully.

You may need to buff them all out. You should also be prepared for the possibility that any nitro finishes may have been ruined.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

I'd start with naptha too.

I suspect it would be bad for the finish, but auto parts stores sell special glass cleaner that takes that film off the inside of windshields that I always thought came from off gassing of the plastic and foam in your car.

But storing your guitars in an unfinished attic? You should find a different solution. If the sticky film is your only problem, you are very lucky. Maybe we've got different attics, but guitars would have serious problems after just a few minutes in mine.

_________________
Mike Lindstrom

as others have stated, this may be a very expensive problem...

from what I've heard on job sites the composition of this stuff has changed over the years and is supposedly 'better' these days...either way I've always thought the chemical makeup of this stuff is most likely suspicious and rife for 'coverups'...

anyway, my worry is that the stuff has reacted to the finish on the guitars and become stuck to it in a way where simple buffing might just shove it deeper into the finish and the heat from said buffing might actually bond it better into the finish...bleh...nightmare scenario if I've ever thought of one...

naptha sounds like a good idea, but I would suggest being gentle with it and try to avoid too much pressure being applied...and 'obviously' choose a good sacrificial lamb to try first

Wouldn't the grunge that was apparent, and its effects, on the exterior finish also be present on the unfinished instrument interiors? And does the instrument owner/homeowner have a homeowner's insurance policy which might cover the remedy to the instruments and mitigate future outgassing problems in the building?

_________________
Peter Havriluk

kerosene - it's a little milder than naptha.

I've heard of some spray foams having devastating effects on homeowners. You should get drywall over that stuff before it becomes a health issue, as well.

Alex

_________________
"Indecision is the key to flexibility" .... Bumper sticker

If one of your guitars is finished with a polyester finish, (any overseas guitars in your collection?) it would probably still be alright. Do you notice that some are worse than others? I'm honestly really surprised that you would run into an issue like this from the spray foam, but it does seem for sure to be in the realm of possibility. Also, generally speaking, you should avoid keeping your guitars in the attic. Attics tend to overheat and get really dry. That being said, I have no idea what your attic is like so maybe you're alright. Best of luck.

Another thought - Did you clean your guitars or something prior to putting them in your attic? If so, did you use something like Orange Glow?

Thanks for the advice everyone. I really wasn't being (knowingly) negligent here. It's a room maintained w/ proper humidity, etc. I never thought the spray foam would do this.

To answer the last question, yes, some guitars were totally unaffected. eg I have a Goodall Koa that's really glossy, not effected. But a Martin OMC-28M and an 80s Gibson ES-335 that got it pretty bad. I'll probably end up taking those ones to a luthier, the rest I can probably manage w/ more elbow grease.

Lesson learned at spray foam!

Aside from the other comments here I can make a couple of suggestion that may help.

I worked as an auto painter for 20+ years between the late 60's up to the mid 80's. I would see all sorts of contaminates on cars from road tar to over spray from all sorts of commercial industries like bridge painting or building paint. So I am familiar with removing "stuff" from finishes.

As was said if any of your guitars are poly finish then they are probably just fine and you should be able to get any residue off with naphtha and/or mild soapy water. So first give this a try:

In a spray bottle fill it about half full with water, then add about 3 or 4 drops of Dawn dish washing detergent. Then you will put about 1/4 cup of Naphtha in. The water and naphtha will not mix so you will have to keep shaking it to keep the 2 suspended so you can spry it out. The Naphtha will not harm your finish so don't worry about that. Do very small areas taking care not to get any in the sound hole or in small joints like where the fretboard overlays the body and where the neck joins the body. In those places just spray it on your rag and not on the guitar.

If it is going to cut anything you should see it work right away. if doing a small area gives you no results then you may have to switch to a stronger chemical. In that case I would suggest going to an auto body supply paint store and buy some wax and grease remover. There are different brands but if you ask them for that they will know what you are talking about. This is stronger than Naphtha so if anything is going to cut it this will.

I am afraid that the residue has reacted with the Nitro finish on some of your guitars. If that is the case then the only thing that can be done is to buff it out. And even then the finish will probably need to be wet sanded with something like 1000 or 1200 grit wet or dry paper and then buffed.

As a reference, a couple of years ago I had a client bring his Martin D18 to me. He played about 4 or 5 gigs a week in small bars and pubs for well over 20 years. His guitar was brown and sticky from cigarette smoke and tar. He brought it to me because his neck so sticky he had a hard time changing chords and wanted me to give it a good cleaning. I tried the above procedures and it removed some of it to the point the guitar looked like wood again but it was still sticky and tacky. The gunk and actually eaten into the finish and left it soft. In the end I finally just decided to wet sand it and buff it out. His guitar was still stained and has a brown cast to it but it did come out pretty well and he was very happy.

If the cleaning doesn't work then I would highly suggest you take it to a guitar shop that has someone that knows their stuff and have them buff it out. It is really easy to buff through the finish especially when trying to remove something like you have so make sure they guy know what he is doing before handing it over to him.

I hope the first step works and this can be removed by a good cleaning and the water/naphtha mix will be you best bet at removing it. Something about mixing the 2 together works better than using them separately (but just remember to keep shaking the bottle to keep them mixed).

I wish you luck and hope this helps.

Bob

Thanks so much for that detailed help. I will try it out this week!

If I had to guess, I'd say that you have nitro finishes on the damaged guitars. Rather than having something ON the guitars that will clean off, I think you might have a situation where the gas from the foam actually etched the finish. I know vinyl and nitro don't get along well. If that's the case, I feel you are looking at refinishing them (or living with the damage).