Agraffe Counterbore Tool

[Farrell]

There is about 1/16" difference between the tenor section and the two treble sections (tenor is higher). I really wasn't trying to grind very much off the agraffes. I was just figuring that as long as I need to grind a little bit for alignment, I might as well at least grind most of that angled lip off - that's all. 

Got it figured out anyway. Turn the agraffe with a slow power tool and clamp the cutter - seems to work like a charm:



Terry Farrell
  ----- Original Message ----- 

  Grinding the v-bar runs a risk of grinding through the hardened portion that is crucial for clean termination.  Wouldn't recommend that.  I don't see any problem with changing hammer bore for each section.  It's fairly common for pianos to vary from the bottom of the tenor to the top of the treble (not to mention bass and treble differences).  Often it's a gradual change (as in Steinway), but sometimes not.  I can't imagine we are talking about much difference hear.  There is a limit to how much you can effectively grind off an agraffe to effect a change.  I don't see any real benefit anyway.  The simplest solution is often the best.    



  David Love

  -----Original Message-----


  I agree with Terry that it would be preferable to keep the hammer bore as consistent as possible.  In manufacturing, the counterboring is done on CNC machines.  It would be very difficult to keep the counterboring consistent, resulting in the strings being in a consistent plane, even if you do get it closer to the treble plane.  Would it be easier, and more even to grind the v-bar to raise the treble, rather than lower the tenor?  Is there room to lower the plate a bit to compensate?



  Frank Emerson





    ----- Original Message ----- 

    Pretty hard to make any significant difference without major grinding of the agraffes.  I'd simply adjust the hammer bore assuming that the bearing is not at issue. 
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