Terry and list, Terry wrote; >Thank you very much Ron for sharing your tool shape with us. . . On >the far right side of your drawing is the end profile of the tool. . >. . I suspect it is the cutting edge, Yes it is. It's not a very good CAD drawing since it was one of my earlier examples from about seven years ago. >- is it more-or-less like a countersinking tool? (I'm sure a grinder >dude would know exactly what it is). My cutter grinding dude uses center drills, then grinds the ends to the profile specified in the drawing. >Also, I do not understand exactly what a donut shape for the agraffe >center is. . Do you go for a continuous arc through the agraffe >center Yes, we look for a continuous but small radius arc through the string hole. I have experimented with both a sharper inner hole (which you get by using an ordinary tapered cutter from each side) and the later version with the small rounded profile. I don't think brass agraffes are very good at the best of times, but the donut shape (the rounded profile string hole) seems to be marginally more serviceable. You will also notice that we run the arc around sufficiently to produce a 0.005" (0.125 mm) clearance with the 20 degree countersink portion of the hole. Again this seems to allow for a slight tonal improvement. > I have a 100-year-old Bechstein waiting for a rebuild in my shop >that has 88 of those little bad boys - they have been staring at me >for more than a year now and I have felt VERY intimidated (although >I have tried not to show it). Thanks big time! It can be intimidating doing some of these rebuilding operations for the first time. But it's a great feeling to get through each obstacle along the way. Regards, Ron O -- _________________________ Website: http://www.overspianos.com.au Email: mailto:ron@overspianos.com.au _________________________
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