Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Applying Superglue to Tuning Pins

Well, I'm happy for you (sorta').

I, on the other hand, would want the CA not only to wick in-between the pin and plate bushing, but to penetrate as far as possible, so that the repair is hopefully extended right down into the pinblock. And to give myself the best chance, I'd spend a bit more and get the thinnest grade available. In fact, even at $2 or $3 an ounce, I'd still consider the money well spent, if it gives me a better chance at success. After buying a bottle of water-thin CA, I did the test to convince myself: I saw it wick into a cracked (but not broken) porcelain plate in a way that normal CA would never do.

But that's just me... Each to his own, if saving one or two dollars is really that important.

I have two questions--

1) I thought I read somewhere that CA glue should not be used on pianos previously treated with pin dope. Is that true?

2) Would one of you chemists out there tell me about debonder? I asked the guys at the hobby shop, "Do you have the antidote to CA glue? I mean, is there anything to help un-glue your fingers if you get some on ya?," and they showed me "Mercury Adhesive Debonder M68DB," by a company called "Mercury Adhesives," but, on the bottle, it doesn't say what it is. Not that that would make any difference to me. I just want to know if it's safe to use on skin. I *can* say that it will melt the gold paint on the plate, so I wouldn't recommend using debonder to try to un-do a stray drip. (Thank God for junk pianos to practice on. When I noticed the paint dissolving, I smeared it around with a q-tip, and somehow pulled that mistake out of the fire with hardly any cosmetic damage. At least, by candle light, the plate surface looked no worse than it was before... )

Thanks!
--Andy

1) Yes, generally speaking in my experience. Pianos that have been doped in my parts were done 20 to 40 years ago, more or less. Since that time the coils, bushings, plates have all turned a dark blue full of gunk. And the loose pins are even looser. So many other problems because of that. Using CA is not something I offer at that point, I just condemn the piano.

But I would not be surprised if high quality super-thin CA, (hot stuff, mercury, bob smit etc.. NOT the walmart stuff) could possibly save some pianos.

2) acetone, I think. I don't buy the debonder, I keep a nice supply of applicators instead.

Jean

PS acetone will get your fingers undone. How safe, health wise, I don't know. I try to use it as little as possible.

All the best.

At 10.95 US$ the 2 oz bottle for Hot Stuff, red label, which is enough to treat a whole pinblock, cost is not an issue.

Here in Mexico City there is Kola Loka, grade D, water-thin CA, at only 4.00 US$ the bottle with 50 ml, (1-2/3 oz). Which is even cheaper than Hot Stuff.

CA costs nothing compared to the alternatives like repinning, shimming with veneer, cardboard or sandpaper/cloth, replacing the pinblock, etc., even at low hourly fees. We can treat a piano in less than 1 hour, 2 hours max for a grand if turned upside down.

God bless CA!

+1

Hi Jean,

I was told at a PTG convention, and I have noticed similar results, that using CA glue on a doped pin block produces a better feel when tuning; smoother, less jumpy. So why not try it out next time you have a doped pin block that has become loose. Let us know what happens.

Like I said I would not be surprised. But if a piano was doped 30 years ago, it was because it was subjected to extreme dryness. Split bridges, cracked soundboard, loose action, cracked key buttons, dried out bushings, mouse nests etc...

CA glue IS a miracle for pinblocks, no doubt.

Case by case. Whatever the customer wants or can afford.

Once again, I would not be surprised that CA could actually save a piano doped with glycerin in the past. It's the rest of the piano that makes me not even want to try.

All the best.

It's always a complicated equation!

Thank you Jean, and Mark, for your replies!

--Andy

Re. debonding CA:

Jean is right, acetone is normally used.

Acetone, to my best knowledge, is not particularly hazardous, but it does dissolve all the skin oils, i.e. it leaves the skin completely dried out. Rather than pure acetone, I would recommend a bottle of acetone-based nail varnish remover. In addition to acetone, it normally contains some water and moisturiser, e.g. lanolin. It is not as aggressive as pure acetone.

Andy, the M68DB is a mixture of acetone and propylene carbonate.
http://mercuryadhesives.com/msds/MSDS_M68DB.pdf

On the other hand, acetone is useful for voicing hammers, so you should have it available anyway,

It works. I just did this yesterday to a J&C Fisher 31xxx.

Interesting scale design with angled straight strung, bichords in the tenor, contemporary unisons in the upper treble and the usual duals and singles in the bass.

This happens to me all the time. Just pull your fingers apart. I haven't found that it's a big deal. In fact it's really good for gluing a cut together. I've found that it helps it to heal faster and no bandaid that comes off. It just wears off after a couple of days.

Absolutely. What is there to lose? Even if it doesn't work then go ahead and have if rebuilt if you want to. The CA glue shouldn't be a hindrance to do that. At least that's what I've understood from rebuilders.

+1

It was used by field medics in Vietnam in lieu of stitches.

Andy,

I saw your post about applying CA glue over other pin dope. Here is my opinion. CA glue loves anything organic. It will bond with anything it can attach to instantly. Therefore, my experience with previously doped pinblocks is that CA glue actually works faster and better under such circumstances!

Now, I will not argue with what Jean has said but it is not necessarily true. There are not always one rotten circumstance after another, even if they do seem to often go together. I also will take exception to what I saw one technician say one time many years ago that if the pinblock had been previously doped, CA glue would produce an over expected result and tuning pins would break off because they are so tight.

In summation, that means that if all other circumstances seem appropriate for trying to save a piano that had been previously doped, go for it! It will probably work very well!

There is a time and place for everything.