<!doctype html public "-//W3C//DTD W3 HTML//EN"> <html><head><style type="text/css"></style><title>shank strike weights</title></head><body> <div>><font face="Arial" size="-4" color="#000000"> What is the benefit or what <is> the noticeable difference of measuring</font></div> <div><font face="Arial" size="-4" color="#000000">>the knuckle, besides making the let off buttons nice and even and look good?</font></div> <div><font face="Arial" size="-4" color="#000000"><br></font></div> <div><font face="Arial" size="-4" color="#000000">I first started measuring knuckle and shank thickness because of what I would</font></div> <div><font face="Arial" size="-4" color="#000000">call a poorly installed set of knuckles and was surprised to find such a wide disparity. Measuring the thickness of many shanks proved to have negligible differences so the differences were in the exactness of pressing the knuckle in. I measure from the top</font></div> <div><font face="Arial" size="-4" color="#000000">of the shank to the bottom of the knuckle.</font></div> <div><font face="Arial" size="-4" color="#000000">Last year I posted about a knuckle caul press for this concern.</font></div> <div><font face="Arial" size="-4" color="#000000"><br></font></div> <div><font face="Arial" size="-4" color="#000000">Subsequent sets measured to have differences between .5 and 1 mm (.020 - .040")</font></div> <div><font face="Arial" size="-4" color="#000000">within the set. I maintain a window of .25 mm (.010"), that's +/- .005" (.125 mm) from</font></div> <div><font face="Arial" size="-4" color="#000000">the average overall shank/knuckle height. I place the bulk (average) of the shanks</font></div> <div><font face="Arial" size="-4" color="#000000">in the center and the +/-'s at the extremes. A more level let off button line was just an interesting result.</font></div> <div><font face="Arial" size="-4" color="#000000"><br></font></div> <div><font face="Arial" size="-4" color="#000000">Action geometry is affected by the size of the knuckle so anything one can do to</font></div> <div><font face="Arial" size="-4" color="#000000">bring uniformity benefits the action.  Priority for shank selection is matching shank SW</font></div> <div><font face="Arial" size="-4" color="#000000">to hammer weight with knuckle height second.</font></div> <div><br></div> <div>Ultimately the best scenario, inertially speaking, would be to graduate the weight of the hammer heads themselves and group same-weight/knuckle height shanks. But most hammer sets are</div> <div>so erratic in individual weights that it takes invasive procedures to have them comply.</div> <div><br></div> <div>Matching shank SW to hammer weight has proven to require minimal intervention for</div> <div>a smooth SW curve.</div> <div><br></div> <div>First, I bore and taper the hammers.</div> <div>Weight them and plot them on a graph.</div> <div>Select shanks accordingly and install them on the rail. (# on underside next to knuckle)</div> <div>Hang hammers.</div> <div>Remove h/s/f from the rail.</div> <div>Cut the protruding shank off with a band saw and rough cut an arc.</div> <div>Set up fence to trim tails on disk sander to even length.</div> <div>Arc tails.</div> <div>Weigh SW and plot on chart</div> <div>Adjust SW</div> <div>Install h/s/f on rail.</div> <div><br></div> <div>I sounds like a lot of work but it goes fast. I like to arc the tails after hanging the hammers</div> <div>to produce a nice finished edge. I also ease the edges (sides and bottom) of the tail molding</div> <div>to remove the sharp corners with a file.</div> <div><br></div> <x-sigsep><pre>-- </pre></x-sigsep> <div><br> Regards,<br> <br> Jon Page</div> </body> </html>