How do I remove Black mold from amp tolex

Markr1

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I'm sorry if I shouldn't ask this question here since it is a ukulele forum and not a vintage amp forum. I thought I would tho since there are some on here that know a lot about guitars and amps along with ukes. I posted this thread in is part of the forum because I didn't think it would be seen by the ones I wanted to see it if it was posted in the guitar area.

I have a 1959 Gibson Explorer GA-18T. The tolex is yellowish tweed looking not actual tweed but looks like it. It is a tolex or vinyl covered and it is original.
The covering is in great condition except the bottom of the amp. It has a black and brownish color mold on about 3/4 of the bottom. I tried Comet and hot water several times to remove the black and it hasn't removed it and I scrubbed pretty hard too. I don't know if some of you guys had experienced this and knew of what may work to get this off. It's really a bummer because the rest of the amp is in excellent shape and all original.
One other problem question also if you don't mind. There is a part of the tolex on the bottom also that is raised maybe a little less then a 1/4 of the surface where it is loose from coming unglued and I'm not sure how to repair it. There are no tears in the tolex so that I could put some kind of adhesive or glue under it to get it to stick back to the cabinet. This was already loose and didn't happen from my trying to clean with the comet and water. I'm guessing it probably happened at the same time that it got the mold from being in a damp place. I was wondering if maybe i tried an iron on low with a rag under it and see if that would maybe help it adhere back like its supposed too or if the tolex was going to have to be cut to add glue under it to repair that part of it. I was wanting to avoid doing that if possible. The older gentleman said he bought it new when he was 15 years old when I bought it from him a couple of years ago and said it spent many years stored in a garage. It even has the original tubes made by RCA for Gibson in it. I took the original gray 59 Jenson PR-10 speaker with the big bell out and replaced it with a Weber Alnico because I had always heard you should do this when buying an old amp like that to avoid blowing the original. I have it put up safe in the closet in the box the Jensen came in so it would stay safe.
I can upload some pictures tomorrow if you want to see the mold and the raised tolex.
I'm sorry to have made such a long thread for these questions I have about it but I just wanted to give all the info I could so someone wouldn't have to waste their time in aking questions back about what I tried or how it happened and so forth. I didn't ask this question on another forum because it seems like a lot of ukelele luthiers and players with experience on this forum don't seem to mind helping us players when we have a problem that we need help with. I've asked questions about guitar related things on other forums such as Gibson and Les Paul and the tele forums and no one seems to ever want to help or don't have suggestions for me and I'm guessing it's probably because I'm not a frequent flyer on them. Most of my time is spent on this forum.

I hope someone can help me with these problems and again my appoligies for asking about a non uke related problem that I need some professional help with.
Thank you all in advance for any input you may have that would help me.

Mark
 
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here are a couple of pics of the tolex that I have so you can see the material and color. I just never took any pics of the bottom because it was so ugly. I'll take a pic of the bottom today after while so you can actually see the problem.

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I did try and google an answer before I asked here and about the only thing I could find was someone said the spray Simply Green might work.
I just took some pics and uploaded of the actual problems. The loose or unglued part of the tolex is in the area of the raised or wrinkled spot you can see in the upper right side.

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Yikes! The back of this amp looks like an actual health hazard :(
There's a spray sold in hardware stores here in the UK called Polyval anti-mould 3-in-1 that would probably work to remove this, but I'm not sure if it's sold in the US. You'd spray it on the tweed, let it work for a bit, then rub it off with a damp cloth / soft brush until all the mould is gone. You'd have to make sure to wear a mask and gloves though. If you can't find it there must be something similar available. The 3-in-1 aspect is important, otherwise the mould will come back.
 
That's actually the bottom of the amp. The back,sides and top look great. I need something I can get in the USA. Thanks regardless for replying.
 
That's actually the bottom of the amp. The back,sides and top look great. I need something I can get in the USA. Thanks regardless for replying.

Oops, it's called Polycell, not Polyval. I had a quick look at their stockists list and they're not sold in the US unfortunately :( But there must be a similar spray available at Home Depot I suppose?
 
I'm looking forward to other replies but I'm hoping Rick Turner sees this and can help. I know he is a guitar player from way back and I'm sure he's got a history with old vintage amps and would know what I need to do or if it is even possible to get rid of it without having to replace. My preference is to keep the tolex original as we all know replacing would devalue the amp big time. High dollar on these amps in the condition and originality of mine minus the bottom being screwed up are anywhere from $900 to $1300. I just saw one on eBay go for $1250 plus shipping but the bottom wasn't messed up.
I'm still welcoming others thoughts but can you give me some good professional advice Rick Turner?
 
I did read on one google that bleach with water works but that would probably just kill the mold and don't know that it would do anything for the stain and don't know what kind of effect it would have on the original color of the tolex. Better wait till I hear more on the subject before I try that one.
Another one I read was Lemmon oil and rubbing it out with steel wool. The Lemmon oil I wouldn't be as concerned about as what the steel wool might do to the tolex. I do have some 000 steel I think.

I read also that Super Glue or contact cement would work for gluing down the tolex tho it was mentioned to not try and adhere it immediately with the contact cement due to it need to dry just a little before putting it back down.
Also heard someone mention on another site that they used Gorilla glue but I don't think I've heard to many good things about it when it comes to musical things.
I'm unsure of any of these things I just mentioned, just going off what I read. I'm waiting to here other opinions here before I do anything. I doesn't look as bad in person as it does in the pics but I know now after seeing them in the pics something is going to have to be done about it.
 
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Are you sure that is mold? If it is, it's probably in between the tolex and the plywood bottom too. Either way, I would be tempted to cut out the tolex on the bottom leaving an inch or so over lapping, or at least cut a slit to see if the ply is rotten or damaged. If you take a small hammer and tap on the bottom are there any soft spots? It looks like it was sitting on a concrete floor for years and had water/dampness condensing on it. May not be mold but water damage.

I would float your questions to this guy.

http://www.vintage-amp.com/
 
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It sounds and feels solid when I tap on it and there is no sign of damage when I look at the bottom from the inside. After looking at it again I guess the only part that may concern me about being mold are the black spots. The brown parts are probably okay I would guess but there again I don't know for sure. I would hate to cut out a part of the tolex if I didn't have to. I wouldn't have a problem taking a blade to it and splitting it a little to check which I'm probably going to end up having to do anyway to get some glue in there to get the tolex back down. I am going to wait to hear a pretty for sure confirmation from someone before I do go and do anything. I've learned over the years with things like this if you don't know then don't do it unless someone that does know tells you otherwise.
Are you sure that is mold? If it is, it's probably in between the tolex and the plywood bottom too. Either way, I would be tempted to cut out the tolex on the bottom leaving an inch or so over lapping, or at least cut a slit to see if the ply is rotten or damaged. If you take a small hammer and tap on the bottom are there any soft spots? It looks like it was sitting on a concrete floor for years and had water/dampness condensing on it. May not be mold but water damage.

I would float your questions to this guy.

http://www.vintage-amp.com/
 
I do appreciate your input tho and Thanks for the offer of info that you know and are able to suggest..
Are you sure that is mold? If it is, it's probably in between the tolex and the plywood bottom too. Either way, I would be tempted to cut out the tolex on the bottom leaving an inch or so over lapping, or at least cut a slit to see if the ply is rotten or damaged. If you take a small hammer and tap on the bottom are there any soft spots? It looks like it was sitting on a concrete floor for years and had water/dampness condensing on it. May not be mold but water damage.

I would float your questions to this guy.

http://www.vintage-amp.com/
 
It sounds and feels solid when I tap on it and there is no sign of damage when I look at the bottom from the inside. After looking at it again I guess the only part that may concern me about being mold are the black spots. The brown parts are probably okay I would guess but there again I don't know for sure. I would hate to cut out a part of the tolex if I didn't have to. I wouldn't have a problem taking a blade to it and splitting it a little to check which I'm probably going to end up having to do anyway to get some glue in there to get the tolex back down. I am going to wait to hear a pretty for sure confirmation from someone before I do go and do anything. I've learned over the years with things like this if you don't know then don't do it unless someone that does know tells you otherwise.


I hear ya there, patience is a virtue! That guy at vintage amps may be able to fit you a new piece of tweed on the bottom without recovering the whole thing. Anything would look better then what it looks like now.

I used to work on wood boats/yachts for years when I lived in Southern California. Restored quite a few too. If I had a dollar for every square foot of rotten mold infested marine plywood sub-decks I've seen, I'd be a wealthy man right now :eek:
 
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I just now saw the site you posted at the bottom. If I can't get help here I'll probably send him a message. Thanks for that. I believe there is someone here that knows tho because there's not much that he doesn't know from what I gather from his previous posts I've read. If he says it I feel he's 100% correct or he wouldn't say it.
I don't know him personally but I do know he's got a lot of knowledge when it comes to music and musical instruments.
Are you sure that is mold? If it is, it's probably in between the tolex and the plywood bottom too. Either way, I would be tempted to cut out the tolex on the bottom leaving an inch or so over lapping, or at least cut a slit to see if the ply is rotten or damaged. If you take a small hammer and tap on the bottom are there any soft spots? It looks like it was sitting on a concrete floor for years and had water/dampness condensing on it. May not be mold but water damage.

I would float your questions to this guy.

http://www.vintage-amp.com/
 
This is just a guess because it's hard to tell from a photograph but that looks to me like a case of varnished tweed. I think most of the tweed coverings that early were actually cloth, but it wasn't unusual for guys to shellac or varnish them.

If it was varnished after the mold started then all the scrubbing in the world is not going to remove it.

Also, just because a mold is black doesn't mean it's the dangerous stuff. The dangerous mold is black and fuzzy or powdery and the reason it is so dangerous is because it gets into the air and is easily breathed. If this stuff is underneath a coat of varnish then it is likely not even live mold but the remnants of what was there when the varnish was applied.

In any case it's certainly worth investigating the chances of removing it without damaging the amp but I don't think I'd panic and do something that would damage the value of that old beauty.

Actually...I just went back and looked at the pictures again. I knew something didn't look right... I'm pretty sure that this amp has been recovered - all except the bottom panel. Unless it's a trick of the camera there is a drastic difference in both texture and color between the bottom panel and the side panels. If the amp has been recovered (and apparently with a modern "tweed tolex" such as that used on new Peavey amps) then the collector value has already been damaged and you might as well have the bottom panel recovered to match.

John
 
Thanks John, I appreiciate the response. I think your not exactly right about the tweed thing. This is the way the old Gibson amps were. They were made to look like tweed but never actually had a real tweed covering on it. It also has not ever been recovered in its lifetime. This is the original covering. Maybe the photos are deceiving. I may not know what to do about this problem but what I do know is my vintage Fender and Gibson amps. Early Fender amps were in real tweed but not Gibson. I'm not trying to piss you off but I can tell you just about anything you want to know about these vintage amps Fender and Gibson as I have had many over the years and it and the covering is original. As I said I'm just not sure what to do about this problem with this. I agree with you that it's probably not a bad mold and maybe it won't scrub off but I'm still waiting for an expert to let me know what I need to do about it.

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Just thought I would add a few more pics of the original tweed looking tolex. These are both 1959 Gibson amps. The one on the right is the 59 Explorer Ga18T. The one on the left is a 59 Gibsonette GA-8 with yellowish blonde tolex covering.

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I got some SOS pads today to possibly try on this monster!!
 
Hi Mark. If that is synthetic you might want to go to a local boat store and get the mildew remover that they sell for vinyl. It works well on boat seats and isn't expensive. Just a though.

Good luck
 
Thanks Vanflyn. I think you may have just hit it out of the ballpark on that answer. That was simple enough. I'll check it out. I do still need to know about the glueing part tho. Do I put a small slit in the tolex or not to get some glue in there??
Hi Mark. If that is synthetic you might want to go to a local boat store and get the mildew remover that they sell for vinyl. It works well on boat seats and isn't expensive. Just a though.

Good luck
 
It is entirely possible that the tweed was adhered with a form of hide glue, and if so, then the glue is "food" for mold. I think the suggestion of a an anti-mold product from a boating store is great. At least it's the bottom of the amp.

Great amplifier, though!
 
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