Loose Tuning Pins
By Craig Brougher
Charles Flaum and Bruce Clark each had some noteworthy comments about loose pins that I wish to further elaborate on because this is a subject so very important, and because it is so difficult to let your friends know where you are coming from via one or two letters. Charles Flaum wrote:
>While it is true that many rebuilds and manufacturers use pin driving
>fluid (I use eggshell varnish) or powder (Steinway uses a substance called
>French Talc), you are the first person I've ever heard of using Pin-Tite.
>I don't claim to know anything about Pin-Tite's chemical composition.
>However, of all the other substances I've heard of being used as pin
>drivers, Pin-Tite is the only one whose primary function is to increase
>the torque of a tuning pin. Why you need to do that in a new block is
>beyond me, unless your drilling technique requires it. Quite frankly,
>my pins come out tight enough and if I used a substance that increased
>torque I'd be afraid of snapping off pins in the first chipping.
As we all can attest, French Talc does not prevent loose tuning pins later on. Steinway and most every other piano manufacturer show loose pins, too. The talc and the lacquers are primarily for lubrication when driving pins to prevent damaging the surface of the drilled hole. The lacquer additionally has a soap, a chalk, or a talc in it which smoothes the turning of the pin. It all aids in tuning. None of it actually impregnates the wood pore, however. The wood entrains the lacquer, but does not absorb it. Therefore, the lacquer cannot seal the wood integrally-- only superficially.
This is where Pin-Tite comes in. Pin-Tite cannot make pins tighter than the new wood hole, unless the hole is drilled sloppily. In other words, it cannot over tighten a pin. On the other hand, you can drive pins into undersized holes easily with it, and then the pins can snap off when you turn them. But that isn't the fault of the Pin-Tite. That would be the rebuilder's fault. It also evens out the torque beautifully. Every pin turns just like every other pin.
Pin-Tite treats the surface of the hole but also deeply impregnates the wood around each hole microscopically-- unlike lacquers and powders. So what you have will be a permanently "hardened wooden sleeve" which has been chemically stabilized at the microscopic level and will stay that way. It resists distortion and so draws its strength from the surrounding pin plank by distributing the force more evenly. You could say it forms the perfect pin hole, having a graduated hardness and pore stabilization.
If I understand correctly, Bruce Clark and Peter Nielson agree on the following:
>Peter Neilson was told the right way was to apply it weekly for six
>months, I was told every day for a week or so until the bottle is used
>up. The bottle I have only says to apply slowly to the top of the tuning
>pin, "as much as the wood will absorb." It also says to "Tune immedi-
>ately, or as soon as pitch will hold."
This is just not true for Pin-Tite at all. Take it from a guy who has used this product for 30 years, fellows. Any old piano that required even a third of a bottle would be restrung and repinned, around here.
Pin-Tite isn't a cure-all, and it isn't designed to tighten pins in a totaled out plank by soaking up an entire bottle to see if you can get the pins to hold. It also does not work in a cracked up plank. That is a mis-characterization of the product.
The following quote might seem to "label" several people mentioned, and so I respectfully take exception to it. I have already said that I have rebuilt hundreds of grands, and each one received a new pin plank. I have also pounded pins many times. I simply made the stipulation of supporting grand planks.
>Tom Steuer suggests over-size pins, Charles Flaum suggests driving them
>deeper or new pin block and Craig Brougher suggests pin tightener and
>would not recommend driving deeper on grands. (Would this also be true
>for uprights?)
Neither Tom, Charles, or myself seemed to subscribe to one of the other methods exclusively, and I'm sure they would agree to that. Bruce Clark remembers the pin dope and the mushy feel, and without reading further, has apparently consigned Pin-Tite to the same characteristic, below:
>As a retired tuner and player technician, I can say that any piano that
>I ever tuned which had been treated with a pin tightening agent, made the
>pianos very difficult to tune due to a certain amount of sponginess that
>the chemical created in the pin block. It was sort of like tuning a
>piano with pins set in bubble gum. It made the pins difficult to "set".
>The familiar "jump" in a tuning pin, that only piano tuners are aware of,
>is gone.
Check out my last letter, Bruce. This might tell everybody interested in this subject how little Pin-Tite is actually used, and how much of the other stuff is substituted instead. This is why tuners feel that all pin tighteners are the same. Kinda like player rebuilders, isn't it? Once stung, twice cautious.
Charles felt that I was accusing him of failing to support his planks. He wrote:
>Really!?! Please, Craig -- give me a little credit. Not only will an
>unsupported block definitely crack, but you've got a damn good chance of
>cracking the plate. I know, because I do quite a few insurance appraisals
>and have seen what incompetent technicians can do.
The MMD is dedicated to automatic musical instruments, and as their owners can attest, very few tuners even wish to be seen in the same house with one! The _majority_ of tuners in my town won't even tune a player piano because they're afraid of them. (If they dropped a wedge, what would they do?) So when we speak to piano problems here, we are directing our comments specifically toward the player genre. That means if a letter advises readers to pound down their tuning pins, and doesn't tell them to remove all the player action and piano action between the pin and the keybed, it won't be done!
It isn't that I don't give a professional rebuilder credit for knowing better, and it was too bad that Charles took it personally. It IS, however, a fact that many owners will try this without knowing any better. So unless he has _specifically_ told them to support the pin plank, they will do only what he has told them to do and no more. Neither I, nor anyone else can give credit where it is not due. Half of the information required can be more dangerous to their instrument than none at all.
So Charles, if you tell us how to do something without happening to mention that they can ruin their instrument by failing to do something else, then don't blame the guy who thinks to mention it!
I think the overall answer to the subject is, "There is a time and a place for every good thing." There is also a right and a wrong way to do practically everything. If you are not thoroughly familiar with what you are doing and the damage you can cause before you begin, then you should learn all you can about it first. That is how I learned the truth about Pin-Tite. I didn't just take somebody else's word for it that it wasn't any good. Then I ran some experiments of my own, and I learned about what it could and could not do.
Craig Brougher
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(Message sent Mon 3 Mar 1997, 16:18:53 GMT, from time zone GMT.) |
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