I do not use either the Jaras or Spurlock jigs, but rather the Fandrich Hammer Gluing Platform. In conjunction with the platform, I use a plain straight edge, (no calibrations or writing on it), and sliding adjustable square. I do not "arc" the tails until after they are hung. (Also, I taper the sides of the hammers after they are hung. This gives me a straight side to guide on.) I do set samples per the existing and optimum strike point, on each end of each section. The platform assures that the tails are all in the same plane, thus, if the strike point is where I've determined, then the "Vertical Pitch" will be correct throughout the entire set of hammers. If I find that the strike line needs to be anything other than straight, then I simply prop the shanks on aluminum angle iron, that rests on the wippen/wippen rail. When I do this, I set samples in several spots in the section, as was previously mentioned. Using the straight edge at the shoulders and the tails, seems to get the job done in the "off" sections. Finally, when doing the "off section(s)", I use an adjustable "vertical", which consists of a base, (filled) with lead/epoxy) and a 16" black iron rod, mounted vertically, to sight against. This rod can be bent for some situations where the "tilt" of the hammer(s) is appopriate for clearance, etc. It probably sounds crude, but it is the most flexible sytem, once you get used to it. I personally find that there are too many variables for the "jigs" to handle completely. Spurlock's tools and jigs are top notch. Best Regards, Joe Garrett, RPT, (Oregon) Been There, Didn't Like It, So I'm Here To Stay! [G}
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