I agree with the quick-out method for keeping the heat down while removing tuning pins. We've been doing it for twenty years without problems. We lower the tension, mike the scale (you can't always trust a standard scale or even a stamped-on one), shear the beckets, then zip the pins right out of the coils. We then grab a handful of strings and lift them out. The piano can be naked in no time. Two caveats, though: 1) You have to be sure the beckets ARE sheared, or you're in for a surprise. However, if you watch the string as the pin starts to turn, it moves funny if it isn't sheared, and there's time to stop, especially with an air-powered tool. 2) If the pin was bent as it was driven in originally, or if the wrench or drill isn't in line with the pin, it can wobble suddenly and severely, wallowing the top of the hole. For this reason, it's okay to have a somewhat sloppy fit on the tip you use for removal - it actually helps minimize the wobble. Although we replace blocks more often than not, our relatively benign climate makes re-use of good-quality blocks an option in some cases, so it pays to protect the holes. The amount you turn the pins while letting down the tension has a big effect upon how easy the beckets are to shear. Do the let-down in any sequence you are comfortable with (alternate rows or whatever), but I think we limit it to about a quarter-turn or a little less. Use a shearing tool that is the right size - too small and it sticks on the pin; too large and it doesn't always do a good job of shearing. Almost any speed above about 300 RPM is sufficient to keep the pin cool enough - it just needs to be fast enough so that the torque on the pin allows you to pull upward as it spins (the pin comes out faster), and not so fast that things get out of control Bob Davis, RPT.
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