Dale, I leave the shanks long and glue the tapered but un-arc'd heads thereon. Once the glue dries I remove them from the rail and cut the protrusion off on a band saw and follow thru with a rough cut on the arc. Then arc on the Spurlock jig. Now I do the final weight graduation. There is minimal change needed because of the manner in which I selected the shanks for mating to the hammers: For example, the M I'm starting today, Ronson Wurzen Felt Hammers, Abel Shanks. Bore and taper hammers. Weight hammers and plot on a chart. This full tapered-shank set will start with mic'ing the shank widths to divide them into four or five groups for bass to treble installation. Each grouping will then have their SW's measured and sub-grouping made. Weights will range from as low 1.4 to 2 or more grams, that could be as many 7 groups. Then I will mic the knuckle height to sort further. I'll endeavor to group similar heights for a smoother regulation during the shanks selection process. Now comes mating the shank to the hammer. Looking at the chart, I determine about where the SW of the shank will place the overall SW curve and select a shank to bring the hammer weight respective of that curve (the curve will be about .3g above a target regulation SW since the tails have not yet been arc'd). My reasoning for this is the jaggedness of a hammer weight curve and shank SW's. Let's say that one were to simply install shanks right out of the box in order. A 2 g shank could be place next to a 1.6 g shank. Now what if an 8g hammer were set on the first and a 7.6 on the second. Their respective SW's would be 10 and 9.2; almost a gram! However, if the shanks were swapped then each SW would be 9.6. A much better solution than having to sand down the first and add lead to the second to achieve the same result. If one were to really indulge in the inertia craze then you'd have to weight the hammers first to a curve to mate with similar weight shanks. More work than I think is really necessary since that inertial effect is probably lost through the lever train. I better get to work... Jon PS Merry Christmas
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