Wim, I suspect using CA would probably solve the problem. The thread that we're looking at is called an Acme Thread. It's characteristics are the square shouldered threads. A very strong thread, usually found in house jacks and such. Why the heck it was put on a tuning pin defies logic, imo. Del? Any thoughts on that?<G> The head is commonly known as an oblong or oval type. The way it was originally made was to cut threads on the a piece of round stock and then heat the tip in a forge. Once hot enough, it was "swaged" to that configuration with a large Sledge Hammer, (which has other names as well.<G>) then the whole thing was "quenched" to harden the metal. BTW, some of you have mis-read the original subject line to say it is a Broadwood. It does not say that. I could not find any reference to a "Geo Brodbent" anywhere, so have no idea who/where it was made. Since it came from S. Aftrica, it might be some off brand or Stencil brand that was sent to S. Africa who knows when.<G> That's my take on this. Joe ----- Original Message ----- From: To: joegarrett at earthlink.net;pianotech at ptg.org Sent: 9/22/2011 9:28:57 PM Subject: Re: [pianotech] Geo Brodbent Tuning Pins The one "Unique" thing, I noticed, is the really course/deep threads! Wow! that's really a new one on me! I've seen this kind of pin on one other piano. I believe it was a Broadwood straight strung grand from about 1885. There were several pins that wouldn't hold, so I was going to put in larger pins. But when I took out this "screws" pin, I showed the customer the problem, and told that unless she was willing to spend the money for a new pin block, etc. the piano could not be tuned. That's the last I heard from her, although I later learned she gave it to a friend, who was desperately trying to find someone to fix it. I think it more or less made the rounds in St. Louis. Wim -----Original Message----- From: Joseph Garrett <joegarrett at earthlink.net> To: pianotech <pianotech at ptg.org> Sent: Thu, Sep 22, 2011 6:16 pm Subject: Re: [pianotech] Geo Brodbent Tuning Pins Dave Smith said: "encountered a Geo Broadbent straight-strung grand piano with tuning pins as shown. Piano is over 100 years old. Although the pin shown is a bit chewed up from some previous tech (not this one) using vise grips, it it pretty close to the other undamaged ones still in the piano. No tuning lever tip I have seen will fit this, as the pin is rectangular in shape, .2?x.26? roughly. The pins are threaded into the block with a pretty coarse thread. Does anyone know where to find a hammer tip that would fit this type pin? The piano was moved here from South Africa, where apparently the techs had no trouble tuning it :} Also the piano is sitting at about 100c flat to A440, but I was assuming it was designed to be tuned at A415 anyway. Any thoughts on this also? Thanks" Dave, Your Assumption that the piano should be tuned at 415 is not a good one. IF there are structural issues then it needs to be repaired and tuned to it's original designed pitch. Most pianos of 100-150 years of age were designed to be tuned to at least 435. If it were German, probably 450 would be what they designed it to be tuned to. (Check Helmholz, in the back Glossary, etc.<G>) As for a tuning tip to fit it? Jeez, I suspect you've never run into an "oval" tuning pin!<G> Check Schaff. Tips readily available. All of my catalogues are at another site, at the moment, so I can't look it up for numbers, etc. The "oblong Tip" and a "tip adaper" will suffice. Even though, in "the day" a double headed head/tip configuration was used for efficient tuning of any piano that had these type tuning pins. The one "Unique" thing, I noticed, is the really course/deep threads! Wow! that's really a new one on me! Thanks for sharing. Regards, Joe Joe Garrett, R.P.T. Captain of the Tool Police Squares R I -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110922/ac056dc9/attachment.htm>
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