I've been meaning to post photos of a hammer boring jig I worked out. It uses an "off the shelf" cradle style drill press vise... cast iron, relatively inexpensive ($60 Palmgren Vise @ ENCO) . The trick was figuring out what the cradle's axis of rotation was. I worked out the geometry, and "proved" its axis of rotation to within .005". By setting it up the way I have it, using very simple arithmetic I can quickly add shims to the fence and/or hammer molding base to place any width of hammer or any molding thickness dead on the axis of rotation.(I generally measure the variation in hammer thickness on samples from the set and decide on a mean value). I'd be happy to share the geometry needed to set this up with anyone who's interested. Comments and improvements welcomed! At present it's not set up accommodate non-90 deg rakes. I think I know how to do that, but its not something I anticipate needing right now...so modifications are on a back burner...or rather, well, not really on a burner at all. The fence is not set up with a stop, since my process starts by boring to a drawn line on the molding. A fence with a stop would be easy to work out. Jim I -- grandpianosolutions.com (under construction) Shirley, MA (978) 425-9026 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090502/50ac64f1/attachment-0001.html> -------------- next part -------------- A non-text attachment was scrubbed... Name: P1020220.jpg Type: image/jpeg Size: 35210 bytes Desc: not available URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090502/50ac64f1/attachment-0004.jpg> -------------- next part -------------- A non-text attachment was scrubbed... Name: P1020227.jpg Type: image/jpeg Size: 18870 bytes Desc: not available URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090502/50ac64f1/attachment-0005.jpg> -------------- next part -------------- A non-text attachment was scrubbed... Name: P1020222.jpg Type: image/jpeg Size: 32795 bytes Desc: not available URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090502/50ac64f1/attachment-0006.jpg> -------------- next part -------------- A non-text attachment was scrubbed... Name: P1020228.jpg Type: image/jpeg Size: 34272 bytes Desc: not available URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090502/50ac64f1/attachment-0007.jpg>
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