Wow Frank, great sketch! <br><br>Hmm......<br>So, if the shank flex causes upward scruff, and the offset axis causes downward scruff, then could they be "tuned' to cancel each other out?<br><br>Intuitively, it seems like scruffing and flex are both power and clarity robbers. Could super stiff shanks help minimize both?
<br><br>Steve Fujan<br><br><br><br><div><span class="gmail_quote">On 11/24/06, <b class="gmail_sendername">Frank Emerson</b> <<a href="mailto:pianoguru@earthlink.net" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">
pianoguru@earthlink.net</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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<div><font face="MS Sans Serif" size="2">How can scruffing occur unless the hammer shank flexes? It does flex, and it does scruff, but always upward. As the flagpoling of the shank reverses, the hammer begins to scruff downward just as it is rebounding from the string. The proximity of the axis of rotation to the string is less significant than the length of the hammer bore from the strike point. This can be seen in slow-motion photograph of action movement. It is amazing how much an upright shank flexes. You would think it would break before flexing as much as it actually does. A grand shank flexes also, but not nearly so much. The drawing below is simplistic and exaggerated, but illustrates the point.
</font><img alt="" src="http://mail/?realattid=0.1&attid=0.1&disp=emb&view=att&th=10f1d442323368aa" align="bottom" border="0" hspace="0"></div>
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<div>Frank Emerson</div>
<div><a href="mailto:pianoguru@earthlink.net" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">pianoguru@earthlink.net</a></div>
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<blockquote style="border-left: 2px solid rgb(0, 0, 0); padding-right: 0px; padding-left: 5px; margin-left: 5px;">
<div style="font-family: Arial; font-style: normal; font-variant: normal; font-weight: normal; font-size: 10pt; line-height: normal; font-size-adjust: none; font-stretch: normal;">----- Original Message ----- </div>
<div style="background: rgb(228, 228, 228) none repeat scroll 0% 50%; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial; font-family: arial; font-style: normal; font-variant: normal; font-weight: normal; font-size: 10pt; line-height: normal; font-size-adjust: none; font-stretch: normal;">
<b>From:</b> <a title="sjfujan@gmail.com" href="mailto:sjfujan@gmail.com" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">Steve Fujan</a> </div>
<div style="font-family: arial; font-style: normal; font-variant: normal; font-weight: normal; font-size: 10pt; line-height: normal; font-size-adjust: none; font-stretch: normal;"><b>To: </b><a title="joegarrett@earthlink.net" href="mailto:joegarrett@earthlink.net" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">
joegarrett@earthlink.net</a>;<a title="pianotech@ptg.org" href="mailto:pianotech@ptg.org" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">Pianotech List</a></div>
<div style="font-family: arial; font-style: normal; font-variant: normal; font-weight: normal; font-size: 10pt; line-height: normal; font-size-adjust: none; font-stretch: normal;"><b>Sent:</b> 11/24/2006 12:47:45 PM </div>
<div style="font-family: arial; font-style: normal; font-variant: normal; font-weight: normal; font-size: 10pt; line-height: normal; font-size-adjust: none; font-stretch: normal;"><b>Subject:</b> Re: Over-Strike vs Under-Strike
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<div><br></div><font size="2">Shifting slightly to the concept of scruffing... The hammer contact will always "scruff" towards the hammer pivot axis (unless the pivot axis could somehow lie in the plane of the string). The closer the pivot axis is to the string, the less "scruffing" will occur.
<br>Steve Fujan <br><br>
</font><div><span class="gmail_quote"><font size="2">On 11/24/06, <b class="gmail_sendername">Joseph Garrett</b> <<a href="mailto:joegarrett@earthlink.net" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">
joegarrett@earthlink.net</a>> wrote:</font></span>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><font size="2">Upon reading the follow-ups of Jons query, I'd like to wonder which is<br>which. I've always considered "Over-Strike" as the Downward angle of the
<br>hammer, which would put the hammer Beyond Perpendicular. ??? Am I correct <br>on that? If so, then, "Under-Strike" would be, where the hammer does not<br>achieve Perpendicular, on contact?? The "Over-Strike" hammer, (on an
<br>Upright), would "scruff", (for lack of a better word), downward, at impact. <br>The "Under-Stike" hammer would therefore "scruff" upwards.<br>Do I have all of this backwards? Confused minds need to know what the
<br>consensus is.<G><br><br><br>Joseph Garrett, R.P.T.<br>Captain, Tool Police <br>Squares R I<br><br><br></font></blockquote></div><font size="2"><br></font></blockquote></div>
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