> > Jim, > Here's a few for mine. Mine differs from Del's somewhat. I chose to > lift the bridge to a hold down rather than lower the entire cutter and > carriage assembly onto the bridge. The result is similar, but the > construction is simpler. The aggravation of height adjustment within > the bridge set is, however, common to either. I used a 2" diameter > shaper cutter, and powered it with an old router, stepped down with > timing belts and pulleys to provide both the appropriate rpm range, > and adequate power. > > Ron N > Thanks Ron. I'm playing with the various geometries and choices involved, and it helps to see something in the flesh. As I play with various radius cutters, I'm staring at and wondering what relief is actually required to safely stay out of the way of the string excursion. Obviously it varies treble to bass, but immediately after the pin, I wonder what clearance is actually necessary. A 7-1/2" cutter would allow me to get away with a relatively easy (keeping in mind that, relatively is a relative word) table saw jig setup I have in mind, but looking at the cut in the shop, I think I would have to follow up the machine notching with swipe of a chisel(darn, but still allows me to use a laminated cap). With the 2" cutter, that's probably a 1/2" shaft you've got there. What is the clearance between cutting arc and the top of the pillow blocks you used? With that size cutter, the way I figure it, its probably about 7/16" clearance. Also with that style cutter have you noticed a tendency to beat-up the side cut of the notch. Cutting rabbets with flat top groovers can be prone to tearout, and in this case I see the side of the notch, from the cutter's perspective, as the moral equivalent of a rabbet. ...On the kitchen table, sits the all important "back-of-the-envelope"....upon this precious piece of discarded paper, accompanied by lovely splatterings of tomato sauce and cantaloupe pits, all my important design decisions are made... Jim I -- Jim Ialeggio grandpianosolutions.com 978- 425-9026 Shirley, MA
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