To Vince, and List: I don't think there's anything special about the way I install hammers, but just in case there is, I'll describe. This technique is for grands; I don't know much about upright hammer hanging, although I've done my share in the past. It's nice to have a high workbench for this project (and some others, too). Try one about chest-high. I like to work standing for installing hammers. It will be very valuable to have a block to raise the shanks to a horizontal position; that way, the resulting hammer line will be perfect __in striking position__. Install trials, last or second-to-last hammers for each section. Use originals or your best guess for position. Then try the positions in the piano for optimum tone. If any need to be repositioned, do so; then test for optimum tone again, to be sure. When satisfied, proceed. Ream hammers for a nice fit on shanks. I like them just barely tight enough to stay put on the shanks at the right position, yet easy to spin on the shanks. As I ream and fit, I leave the hammers on the shanks, not glued. Begin with treble-most section. (These are the easiest since they are bored straight. By the time you get to the tenor and bass, you will be "warmed up" with the technique and it will be easy to accomodate the boring angles.) Glue on the hammers, one section at a time. I use either yellow or hot glue, with about equal preference for either. The upper action is on the workbench, shanks pointing toward me. I start at one end of the section, installing the first hammer next to the already-glued trial. A dab of glue on the shank, another across the hammer hole's front face (side toward the flange). I blow a puff of breath through the hole, which explodes the glue bubble into the hole, coating it evenly. Put the hammer on the shank, spinning it as it goes on, forming a nice glue collar and coating the shank evenly at the same time. By feel and sight, get the hammer close to its ultimate position. (Here, experience with the technique is helpful. You might be able to get something like half of the hammers exactly where they want to be on the first try.) Position the freshly glued hammer using a straight edge long enough to span the section. I test at three points: front shoulder, back shoulder, and the tail in the area of backcheck contact. When all three points are in line with the trials, that's where it stays. There is, of course, the matter of having the hammer plumb. I check this with a try-square against the workbench top. I sight across the blade of the square, checking each side of the hammer (since by then the hammer is usually tapered), looking for an equal angle on each side. (Here again, experience might yield the correct position on the first try.) If the hammer needs to be rotated slightly, do it and recheck with square and double-check position with straight edge. With the first hammer (plus the trials) glued, I go to the other end of the section and install the one next to the other trial. I alternate from one end of the section to the other, working toward the middle of the section. This accomplishes two things: It gives the newly-glued hammer a few seconds to set up without being disturbed by the process of installing its neighbor. And it cuts in half any tendency to accumulate error in positioning the series of hammers in a section. This should be a moot point, since there should be no positioning error. But this might be an added nicety for novices with technique. I should mention that I have a flourescent light fixture mounted on the wall behind the workbench. I can sight against this bright background for a really good view of the alignment of the hammer with the square. This light contributes to the illumination of the whole work area, which helps the whole operation. This setup is helpful for some other operations as well, especially travelling shanks. When the angled hammers are installed, the straight edge is used to align the corresponding __edges__ of the three reference areas, instead of the __surfaces__. It is difficult to describe this, but if you set a straight edge along the shoulders of the original hammers, you'll immediately see what what we're looking for. The tails of the new hammers will be a similar situation to the shoulders, not square to the straight edge - although the original tails will have been squared off. I shape the tails after installing, using a 5-inch disc sander, 36-grit, in my portable drill. They end up perfectly even and parallel, nicely shaped, and with a very nice checking surface. I think that's about it. Questions? - Tom McNeil, RPT - Vermont Piano Restorations
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