Paul R-J said: "That is a full and detailed answer. Much appreciated. I have yet to find the drywall screw solution to be effective in the majority of cases, and almost always cut the shank flush and drill it out. The angle of the hammer bore can be duplicated on the tail of the hammer and followed by eye to get it relatively close. There is always a tiny bit of slop in the drilling job, and this allows for more precision when gluing up. You can also clamp the hammer either to a neighbor or between neighbors while the glue sets up. " Paul, Just to set the record and some facts straight: I invented the method of extracting hammer shanks with the "sheet rock screw" system. However, the original system used a sheet metal screw, NOT a darned sheet rock screw! Sheet rock screws have very sharp threads and help to defeat the purpose of the screw in this use. Sheet metal screws, (specifically 1 1/4" long, with either hex head or slot/pan head. either of which have a flat surface on the underside of the head. sheet rock screws do not!), have a less aggressive thread that will not cut the wood fiber, but simply push it into the thread shape. Originally, I had to find a way to pull almost a full set of Baldwin Hamilton shanks and hammers of a school piano that had been vandalized! At that time I had a cubby hole work space, no drill press and little else to do the deed. (I haven't forgotten what it takes to get up and running, shop-wise.<G>) Using the sheet metal screws, #6 size, did the trick for me. Cut the shank off flush with the butt top and center punch the shank; drill a hole down the shank until you feel it go through the other end of the shank, (there is, almost always, an air pocket <G>). I use a 3/32" drill bit. The math is, this will leave 1/16" of shank wall and the 3/32" is the suggested pilot hole for the screw to get a good "purchase" in the shank. I also use a dilute solution of wall paper remover. Run the screw down the hole, leaving sufficient space to use your shank pulling tool. Heat the screw until the moisture boils/bubbles/steams a bit, or until you percieve that the moisture has almost dissapated. Immediately apply the puller. Disclaimer: This only works on about 90% of the time.<G> It works for all kind of glue, as long as it is NOT CA glue!<G> I hope that clears up the misconceptions about who invented this system and how it works the best. Happy shank pulling.<G> BTW, I use cold hide glue for such repairs, in the field. Trick: put the Hide Glue in a coffee mug with very hot water. Let set while you are prepping the repair, (always dry fit!). The heat helps the cold hide glue to set faster. I'm sure some brainiac will come up with a reason why this is so.<G> Regards, Joe Joe Garrett, R.P.T. (Oregon) Captain, Tool Police Squares R I -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20100911/b5d397d2/attachment.htm>
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