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HI. i'm new to this forum. I have a question about an older piano with a polyester finish. it has some fading and blotching of the wood under a very well preserved synthetic finish. the damage is apparently a result of exposure to sunlight. i'm wondering if it is possible to remove the top coat, or is the piano doomed to becoming ebony? the wood looks like rosewood, but thats a guess.

Three questions.

1. What brand of piano is it?
2. What do you mean by "older"? Five years old? Ten? Thirty? Fifty? A hundred years old?
3. Reason I ask is, is it possibly still under warranty from the dealer?

Disclaimer: IANA piano restorer or wood refinisher.

Bear in mind that the case IS just a wooden box, and you can pretty much do whatever you want to it by way of stripping, refinishing, painting, etc., without affecting how the piano sounds.

thanks for the reply

the piano is a petrof built in 1956. i don't think it has a warranty. the technician i bought it from suggested black because polyester is so hard to remove. but it think its such a shame to cover such a beautiful veneer. i just wondered if anyone had ever tried to remove polyester.

Okay, so you're saying that the piano is wood with a coating of polyurethane (which I'm assuming is what you mean by "polyester") varnish over it? And you're saying that the wood looks patchy or blotchy under the varnish? And that your piano tech suggested simply painting the whole thing black?

Well, piffle.

I mean, like I said, I'm not a furniture refinisher, but I've done a bit of DIY home repairs over the years here and there. Probably what has happened is that the piano was originally stained and that for whatever reason the stain has become blotchy (I have no idea why it would do this, I'm just spitballing here.)

AFAIK any good-quality furniture stripper will remove polyurethane varnish, but what you need to watch out for is whether that's veneer on there, or solid wood, before you go on to the next stage, which is "sanding". If it was me, I'd go down to the library and get some books on furniture refinishing and read up on it. Or hand the whole thing over to a professional furniture refinisher.

But yes, IMO it is fixable without having to paint the whole thing black. I mean, sheesh. :rolleyes:

thanks for the reply. from what i understand, polyester/polyurethane finishes are not easily removed due to their incredible durability. i haven't found much info on the web, but what i have found says that few solvents will even touch the stuff. from the lack of response, i would guess that no one on this forum has attempted it. as tragic as it would be, i think black is the eventual fate of this faded finish . its not really on the agenda at the moment, but i was just curious.

here's something i did find just fyi. i guess my question is answered.

"...I don't recommend polyester just the same. The reason for this is that polyester finishes are by nature VERY thick. They are difficult, if not impossible, to strip with the same implications listed above in discussing catalyzed finishes. In fact, once polyester has been applied to a piece of wood, you will never get it off. You must sand the polyester away and the wood with it. In addition, it is VERY expensive to repair when scratched or dented. Few refinishers are willing to work on polyester either. The reason is that it takes a great deal of work and special materials to do repairs. Also, polyester isn't flammable, it's EXPLOSIVE and, therefore, very dangerous to work with"

Was this where you got that quote from?

Okay, yeah, now that I look it up on the Internet, I see that there is something different called "polyester", it's actually a catalyzed polyester resin bonded to the wood. Bummer.

However, Schimmel says you can get it off using heat.

http://www.thewoodworksinc.com/MCA_Polyester.htm
They also note: So it is do-able, all you need to do is find a furniture restorer who works with polyester.

Here's one.
http://classic-furniture.com/svc.html
One question: Why do you feel you need to repair this? It doesn't affect the piano's sound, does it? Live and let live, say I.

thanks for the link.

why do i want to...just something i'd like to have done one day. i do believe that my piano is first and foremost an intstrument. and the first things that i have done will be on the action. but i want to start looking into refinishing options now so that one day when the time comes, i can make a decision on the type of refinishing to do. pianos are after all a piece of the furniture whether one plays them or not, they are there with the couch, and tables etc. some people like ratty furniture and some don't. personally i would prefer a worn laquer finish to faded wood under synthetic top coat, but this is the piano i have to work with at the moment.

thanks again mathilde

How big are the blotches? Is it something you can cover up witha piano shawl (am I the only one who's old enough to remember those? )

Polyester CAN be stripped chemically. You can contact Restorco at 888-222-9767, or Besway at 615-865-8310. You might ask either Dave at Restorco or Ray at Besway about testing for polyester. I am not sure that a piano that old would be polyester or simply high gloss lacquer. It would be a good idea to contact the piano manufacturer to see if they were using poly at that time before you go through all the trouble. The polyester remover works slowly, and is very toxic, so you must obey all cautions on the labels PLEASE. We have successfully stripped poly with these products, then re-coated with high gloss lacquer. Good luck.......Sam

pianophilic,

If you are saying this is a 1956 piano with the original finish, where are you getting information it's polyester?

Or are you saying it was refinished more recently in polyester?

Regards,

Rick Clark

i thought it was strange to have a polyester finished piano from 1956 myself. but the technician had no doubt. i never thought to test it but i can't imagine an original finish being this shiny without it being polyester; but i'm not an expert and just trusted what i was told.

honestly, the finish is flawless and high gloss except for where the sun has hit and caused an effect almost like bleached wood under the very thick shiny coat. under the lid and in parts of the rim it is a rich reddy brown colour and looks very much like rosewood(also suggested by tech).

it could have been refinished, but i bought it through a technician from the original owner who imported it many years ago from holland. she didn't mention any refinishing. I also wasn't aware that polyester could be applied so well as a second finish.

the pedal lyre and inside of the rim have a different kind of finish...not as shiny. and the pedal lyre is not faded whereas the legs on that side are almost white. i suspect these areas are not polyester.

the technician suggested that the polyester at that time didn't contain UV coating which might result in such fading.

if it was refinished, they did a very proffesional job of it and its too bad the owner didn't keep it out of the sun. because it has barely a nick or scratch.

i will contact petrof to see if they used synthetic finishes in '56. and i'll ask the technician to test just to make sure.

I am not a piano tech, but I do work on antique furniture. Be very careful about using heat on furniture. You can just as easily remove veneer as finish. Anything you do should be considered carefully and tried in inconspicuous spots prior to dousing the piano with a gallon of stripper.

You can test it yourself--keep reading.

Er, not that I don't believe all Piano Techs are gods, but is it possible that you got hold of the one Piano Tech in the known universe who couldn't tell the difference between polyester and polyurethane and lacquer? Techs do tend to be more interested in the insides of the piano, so maybe you just got someone who doesn't know much about the outsides.

I found this on that wood refinishing site.

http://www.thewoodworksinc.com/MCA_Polyester.htm

"Within the last 25 years" puts it at more like 1975, not 1955.

And, again, I'm not a piano refinisher, but I've been looking around on Google, and I can't find anything that says that polyester piano finishes have UV-resistant materials added to them nowadays, let alone back in 1956. All the references to UV coatings or curings that I've been able to find have to do with varnish or lacquer, not catalyzed polyester. I can't find anything at all that refers to UV-inhibited polyester being used on pianos.

This FAQ doesn't say anything like, "If your piano has a UV-inhibited polyester finish, go ahead and put it in the sun." It doesn't mention UV-resistant piano finishes at all.

http://www.pianofinders.com/faqs/ownersfaq.htm#sunlightbad
Sounds like what happened to your piano (yes, I know it's talking about fading the finish, not the wood, but it's still talking about "fading"), so obviously it didn't have any kind of UV-resistant finish, but maybe that's not because they just didn't have them back in 1956--maybe it's because there's no such thing, and your Piano Tech was just talking through his hat. Of course, if Tunerteknica the Goddess of Piano Techs wants to come in here and lambast me with a wrapped bass string and show me where it says that they do SO use UV-resistant coatings on pianos, I will abase myself and accept my punishment with humility.

I found this description of what's involved in applying a polyester finish. I, too, have trouble visualizing this taking place in 1956. I mean, "better living through chemistry" and all, but I didn't think Fifties chemistry was that sophisticated.

http://www.woodweb.com/knowledge_base/Polyester_finishing_techniques.html
And I found this, FWIW.

http://www.kreftingpianos.com/Q&A.htm
So if it's got a mirror sheen, it could be polyester--but it could also be something else, something that's possibly removable.

Anyway, I'd go down to Wal-Mart, get a little bottle of furniture stripper, read the instructions on the back, and test it on the piano somewhere, see what happens. If it looks like it's making headway, then you're in business.

If the finish is that good, and your only problem is sun fade, you might consider having it oversprayed instead of stripped. A skilled touch-up/ finish person can do this a lot cheaper than strip and refinish. It needs to be sanded, then mist coated with the appropriate color to make the fade match the rest, then clear coated with lacquer or polyester. We have done many of these over the years and it works fine and is much less expensive than the whole strip/refinish process.

thanks for all the info everyone!

i heard back from petrof and they say they didn't use polyester in the 50's. so i'll try the paint stripper.

also interested in more infor on the over spraying. can you still see the grain after this process?

pianophilic,Go out and buy acetone.Find a hidden spot of the finish like the rear leg bracket and wipe with a couple drops of acetone.If it is polyester it won't come off.If it is lacquer or other material it will.Your best bet is what Sam said,touch-up by color filling and over spraying.Yes the touch-up artist will also match the grain pattern, if he/she is good.

Overspraying will not hide your grain if done properly, by which I mean using a dye stain (as opposed to a pigmented stain). Dye stains are translucent. The right shade of stain will hide the sun fade without affecting the grain pattern.