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I went to tune an old Apollo Grand today and the tuning pins were looser than I've ever seen on a piano. Quite a few of the pins were so loose that when I turned the pin, as soon as I let go of the hammer it would just float down about a half step in pitch. I've used the CA glue treatment with success, but I wondered if a piano could ever be so bad that the CA treatment might not work. Has anyone had this happen?

Thanks

What's it gonna hurt to try? Take the action out first and put down some plastic on the keybed. Get out the fan and the carbon filter respirator. Hide the children. You might try multiple apps in the worst areas.

If it doesn't work you lost an hour and a few ounces of CA.

I have had numerous successes with CA in pinblocks that bad. The thing is to give it as much CA as the wood will soak up. On some pianos that has been more than one bottle. You make one pass with the glue giving it enough that you see it fill up to the base of the pin. But that will soak in shortly, allowing more to be put in. So then give it a second pass.

As Dale says, make sure you are well-protected below the block from whatever might drip through.

The only time the CA has not worked for me was when there was a previous chemical contamination (I think it was oil/lube), but as long as the wood is unpolluted and capable of soaking up CA it seems to work, sometimes resulting in a better tuning pin feel than it probably had when it was new.

The stuff is amazing. I have never yet had a pinblock that it couldn't fix (even previously doped ones). I use a hypodermic needle to deliver the glue to the pin, it just makes for a neater job than trying to apply it directly from the bottle. You can even use it on an upright without laying it down on its back; the CA is so thin it will wick into the pin anyway.

I'd bet that it's pretty dry indoors...

Be aware that CA needs a bit of humidity to work best.

Is there a special technique to prevent the pins from being glued to the block or do they not stick because they're steel?

Cheers,
--
Don

Thanks for sharing your experiences on this. I'm going to try it with the hypo needle. It sounds like you can have a lot more control than putting in straight from the bottle. I really appreciate the responses.

In answer to your question idylldon, the glue mainly swells the wood and then hardens. It doesn't adhere to the tuning pin. When tuning the pins the first time after treatment there will be a slight tension from the glue, but once the initial bond is broken from the glue the pin turns without being bound by the CA glue.

Although it's too late for this piano, always ask yourself before doping - "Have the pins been pounded in all the way?" Also, "Are there so many untunable pins that it is not economically viable to repin the offending pins?" There is little that I hate more than seeing a piano with pins whose coils are as far from the plate as when it was new that was "doped." One of the main problems it that, once the block is doped, putting new pins in can cause "jumping" pins, making some pianos almost un-tunable. And when the doped pins get loose what must be done then? Either pound them in (which could have been done before doping) or put in new ones (which will probably "jump").

The only time I think doping makes sense is on pianos that are literally on their last legs; pianos which have no real future.

Thanks, Steve. That's what I figured but wanted to make sure in case I ever have to use the technique.

Cheers,
--
Don

I agree 100% IF we are talking about the old method of doping. CA glue is not in any way like doping, that's why we no longer use the term when referring to CA. Pins will not jump with CA, as a matter of fact, I have done a few grands that were doped and jumping, and the CA cured both. So far, success rate for loose pins is 100%; jumping pins, maybe 50%.

This piano needs a lot of major work that really isn't worth putting into this instrument. The main concern here is just getting it tunable. I wouldn't even consider suggesting that this piano have new strings put into it without a new pinblock. So this procedure is definitely in the category of a bandaid until they can afford a better piano. I'm grateful to hear that this should accompish that goal.

Thanks,

Tell me a little about CA glue.

CA is cyanoacrylate, or super glue...

Make sure you get fresh bottles. I always go with the brands available at good hobby shops. (Hot Stuff, Pacer, Bob Smith - I know I'm leaving out quite a few others.) I've been told to avoid the stuff you can get at hardware stores or grocery stores - apparently there is something added to those little bottles to extend the shelf life.

Bob Smith is my personal favorite because it comes in many different "flavors".
http://www.bsiadhesives.com/

I've used the rubberized ones a lot because regular CA tends to form a brittle bond. (not for tuning pins though)

For tuning pins, I use thin, a little at a time. The temptation is to dump a lot at a time, but that just makes a mess. Let it soak in a little and repeat if needed. I keep a bottle in my kit so I can add a drop or two as needed. On real lost causes I have added a bunch more - this time of year a fine mist of the accelerant keeps it all from wicking away from the pins before setting up. If it's real loose, a little thin to wick in, followed with a little thicker one to fill the gap works well.

I'll never pound a pin again...