Greetings, Dale writes: >>To my mind it doesn't really matter how . big the pin is, within reason a no.1 thru 4 pin as long > as they render easily in the block. know what I mean. I think so. I have continuing on with my dial indicators and weights and vise in the shop. Today, I anchored a pin (.271") in the vise and hung ten lbs(which is far more force than I would ever put on a pin with my outstretched arm) on a 10 inch moment arm. Movement at the top of the threads was .0045". I then used a 4/0 pin, (.291") and it flexed .003". Tomorrow I will have the time to see what kind of torque reading I can get to confuse myself with. Given the amount of pitch change to be had without moving the pin in a usual Baldwin block, there has to be a lot of give in the system SOMEWHERE! Perhaps we could get some sample equations from you number monsters out there. How many thousandths of an inch of string movement are requred to create enough additional tension to overcome the friction in an agraffe? This isn't a trick question, I'll never even try to solve it on paper. >> If I pin a new > block with number ones and they're to tight it 's still hard just as hard > to tune as the too tight no.4 >> While I like experimenting as much as the next person, I am finally satisfied with my pin/block/drill combination. The D at Vanderbilt tunes like a dream. I used 1/0 pins from Pianotek in a Steinway plank. I drilled it with a new "C" bit in the bass and middle section, switching over to the "D" bit for the last two octaves. After two years, the torque has remained a around 120 in/lbs in the bass, and a little less than 100 in/lbs in the top. Not a single jumping pin in the piano. I don't notice any additional flex in these pins compared to 2/0. However, the older D with the 4/0 pins does have a bit more rigidity,(which is good,because it is a tight block). Contrast this to our brand new D. The tightest pins in the piano are in the top octave! Geez, and I have to live with this. There is no need for a jumpy pin with 150 in/lbs torque in the top octave of a piano and I consider it an artless stringing job when it makes tuning unnecessarily hard for us tuners. I am beginning to understand why some older rebuilder/techs I know eventually got to where they only tuned their own rebuilds Regards, Ed Foote RPT
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