Check the line magic line between the bottom of the key at the balance rail and the whippen flange center pin. If, at the key half way depressed, the top of the capstan is on or close to the line, then I wouldn't mess with the stack--especially because you already have clearance problems over the rest cushion. Try this: put a small level on one of the unisons running parallel to the strings. Attach a small level (2" type) to the shank with tape. Raise the shank with a string hook until the bubble is at the same position as the level on the string. Since you have a hammer on the shank of known bore distance (it should be less than 2" for this test), measure the difference between the string and the top of the hammer when both levels are equal. Add the difference to the existing bore dimension and that is the point at which the hammer will be 90 degrees to the strings with the shank parallel to the string plane. If the bore must be shortened in order to get the proper blow distance and to get it to regulate properly, then I wouldn't have a problem with that. You can adjust the rake in the following manner. Bore the hammers to the dimension you think you need for proper regulation. Set a let-off rack to the string height for that section using the end hammers as guides. Dry fit the hammer to a shank. Raise the hammer to the string height gauge and while looking from the side adjust the rake so that the hammer is at 90 degrees to the let-off rack. When you are sure you can get the angle you want, apply glue (hot hide would be best here as it sets quickly) and adjust the hammer for rake using the let-off rack as a guide. Do this for the hammers on the end of each section and then use a jig to align shoulders as normal. If you are worried about the angle of inclination of the strings toward the bridge, you can measure by placing a level on the keybed and one on the strings to compare. Use a protractor to see what number of degrees difference there is by comparing bubble positions. If the strings are running uphill and you want to be exact about strike angle, adjust the rake by the same number of degrees difference that you measured between the keybed and the strings. I can't say I would go this far with it. I would be content to rake the hammers so that they are at 90 degrees to the keybed. The angle of the strings upward toward the bridge is not likely to be 3 degrees. More likely it will be at most 1 - 1.5 degrees in the upper treble and less as you go down the scale. Who knows, if the board has collapsed the strings might even be running down hill to the bridge. And that's assuming that the bearing is divided equally between front and back which, of course, it rarely is. And then, it depends on what the definition of is, is. Okay, that's enough... David Love davidlovepianos@earthlink.net
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