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<title>Re: What's the angle on backcheck angles?</title>
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<div align="left">Nay, not so. Excellent help. Never underestimate my ignorance!<br/><br/>Alan Barnard<br/>Salem, MO<br/><br/>
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<hr/>Original message<br/>From: "William R. Monroe"
<pianotech@a440piano.net> </pianotech@a440piano.net><br/>To: "Pianotech List"
<pianotech@ptg.org> </pianotech@ptg.org><br/>Received: 2/22/2008 2:41:50 PM<br/>Subject: Re: What's the angle on backcheck angles?<br/><br/>
<div align="left"><font face="Bookman Old Style" size="2">May take some experimenting Alan, but I agree with Jon, 1-2mm below the tail at drop, and somewhere between 68 and 72 degrees to the key usually works. It's really pretty quick and easy to determine by experimentation, too. Set the check somewhere between 68 and 72, adjust the checking ht, and then check the feel of the hammer when its caught. If you can push the hammer "through" the backcheck, decrease the angle (tilt the head of the backcheck away from the hammer tail). The standard of putting the hammer in check and pushing the hammer further into check while continuing to hold down the key is a good diagnostic. As you push it further into check, the friction (pressure) should increase.</font></div>
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<div><font face="Bookman Old Style" size="2">My apologies in advance if this is like 2+2 stuff for you. Just wanted to be complete.</font></div>
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<div><font face="Bookman Old Style" size="2">William R. Monroe</font></div>
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<blockquote type="cite"><font face="Arial" color="#000000">What's the angle on setting these angles?</font></blockquote>
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<div>Have the face of the backcheck 72 degrees to the key,</div>
<div>have the top 2mm below the tail at 'drop' position.</div>
<div><br/>Regards,<br/><br/>Jon Page</div>
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