<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html>       Richard Brekne wrote: Hi Phil and Ron, I wanted to include an illustration with this bit that I forgot to paste when I sent it.   <img SRC="cid:part1.3E4E209C.AB10ACBF@grieg.uib.no" height=273 width=479> Course there is a difference between the second and third drawings, anyone care to describe that ?   <blockquote TYPE=CITE>Phil wrote The position of the jack relative to the hammer shank has no bearing on the direction of the force being applied at the jack contact point, just as the angle of the hammer head and hammer shank have no bearing on the direction of travel of the hammer strike point. It certainly does. It is in the end the jack that exerts force on the knuckle, and the angle formed between the jack top and the hammer shank line is the critical one. That the jack remains stable for most of the key stroke relative to the whippen center line (and is perpendicular to that line)  allows you to disregard the jack and look only at the whippen center line... because that means the jack top is on that line. But this changes the minute you hit the jack tender, or better said.. the second you change the angle of the jack relative to the whippen center line.   <a href="https://www.moypiano.com/resources/#archives"></a> </blockquote> -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway <A HREF="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</A> <A HREF="http://home.broadpark.no/~rbrekne/ricmain.html">http://home.broadpark.no/~rbrekne/ricmain.html</A>  </html>