Hi, Timothy
You've had a lot of advice and information about the newer types of CA.
It seems that my approach is now making me firmly in a minority, possibly a minority of one.
I do not treat the entire pinblock, when often only a dozen or maybe two dozen pins are too loose to tune. (Sometimes it's only three or four.) It has been my experience that pins which didn't need treatment feel better when tuning than ones which have been treated. I'll tolerate pins which are fairly loose, so long as they don't slip. One uses very gentle hammer technique on them. It seems like normal playing doesn't throw many out if they are kind of medium loose to fairly loose, just not so loose that the tuning hammer moves down when one puts it on the tuning pin.
By doing this, I avoid the fume problems, because I am using so much less CA. Since treating just a few pins can be done very quickly, I don't make a special appointment to do it. It fits right into a normal tuning session.
My favorite brand is Loctite, water thin, in 5 or 10 gram small bottles. They have a long thin spout and a needle in the cap. The thin spout is perfect for putting a few drops of CA right at the point where the pin dives into the plate bushing?? or pinblock. For an upright, I find I can get it to wick in just fine without tipping. I hold a washcloth under the pin so any extra doesn't drip down and foul the strings.
Sometimes I can still use the glue long after the bottle has been opened, but if the glue is still liquid but there's a clog in the long thin spout, I carry a hatpin which can get through it. Once the glue looks sluggish in the bottle, I toss it. I always keep two or three fresh unopened bottles still on their cards. I sometimes get over a year of use from a bottle before it seizes up. Of course it's crucial to keep it well capped, since it's the humidity in the air which causes the glue to set up.
I first see which pins have slipped so much that they no longer sound like part of a scale. Before doing the tuning, I treat them first. I go back after about ten minutes, see if the note is tunable, and add a second dose if it isn't. I find that usually the second treatment works better than just one, because the first treatment has sealed a lot of the cracks so more of the CA stays at the pin the second time. I've sometimes used a third, but very rarely need to.
Then after a second dose, I return again after ten minutes, gingerly pull it to pitch, and go on with tuning. When I get back to the note in the normal tuning sequence, I'll see if I can adjust it if it really needs adjustment, but if it is a stinker and was hard to get to pitch and is close, I'll fudge a little with the rest of the unison so I don't have to move it again. This is for pianos with basket case pinblocks, of course, the ones which used to be headed to the dump, but I've had good results.
I see no reason to pour ounces of this stuff into a whole pinblock, when it works so well to treat the really bad pins as I tune the piano and leave the marginal ones alone. I sometimes have tuned a piano with a terrible pinblock (like an old Mason & Hamlin grand I enjoyed, otherwise nice) three or four times. Each time fewer notes needed treatment, and they were usually new ones. You can tell because the CA darkens the plate bushing and it's shiny. I don't tend to get call backs for notes which slipped, though I solicit them. "Call me if this gets bad again."
For me, the best part of CA for loose pins is that we no longer need to make a big deal of treating the whole piano, as if this is its one and only chance to be fixed. That was the old paradigm, when using the glycerin junk. It was a terrible fuss, tilting, pouring the stuff in, waiting a week, trying to clean up the awful mess, untilting, tuning, and the feeling of the tuning pins was always mushy though they did hold a little bit better.
I've used CA on one of these glycerin-fouled uprights, and the CA worked just fine. The moisture from the glycerin (which is hygroscopic) sets up the CA fast.
Just treat the ones which really need it, leave the rest alone. It takes far less time, you don't even have to charge for it since it takes so little time and glue. It's just a part of tuning an old piano with loose pins. If they get loose enough they can't be tuned, treat, otherwise just leave them alone. Then if a few more end up difficult to tune later, you can always treat them during the next tuning, which should take four or five minutes. Why bother the customer with a new fee and an explanation for four or five minutes of work and 1/10 of a $2.69 bottle of glue? Just keep the small bottle (and a spare) in your normal kit. It barely weighs and thing and it hardly takes any space. Don't leave home without it. And a hatpin.
No driving back, no waiting to tune, no selling a big job, no getting gassed with the stuff, no harsh feeling tight pins which got treated when they didn't need it. And a tiny little bottle costs a lot less, and you don't need fancy applicators, or pouring it out into containers. The container it comes in already has the perfect applicator built in. Why not use it? (Though the new variants do sound interesting ... but only if there were a job which NEEDED ounces and ounces at once.)
This stuff:
https://smile.amazon.com/Loctite-Liquid-10-Gram-Longneck-234796/dp/B0002YXG78/ref=sr_1_5?dchild=1&keywords=Loctite+CA+glue&qid=1619411330&sr=8-5
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