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<DIV><FONT size=3> To all Hammer Heads</FONT></DIV=
>
<DIV><FONT size=3> In the previous thread I was trying t=
o convey the way I see that a hammer is made & if you followed that then=
you see that I have a definition of tensioned felt in mind. However what I =
failed to articulate clearly is that Tension & compression go hand in ha=
nd in the hammer pressing process.</FONT></DIV>
<DIV><FONT size=3> As I stated, & piano hammer makers can =
tell you, that too much tension can be achieved during pressing in the outer=
layers of felt and it can & will rip open in the crown. =
This is the elastic limit of the felt. As the stretching of the felt on=
the outer perimeter happens the inner parts of the felt are compressin=
g. It has too because of the stretching of the outer felt, the tri=
angular shape the felt strip is cut & the hammer press pressure itself. =
</FONT></DIV>
<DIV><FONT size=3> To prove this to yourself take any ki=
nd of tenor or bass hammer & cut thru the molding with a band saw small =
hand back saw up to the tip at the underfelt. Now that the molding is =
separated if it actually has tension the 2 halves of the molding will move a=
way from each other as the tension is released & the middle compressed p=
art will unload. Squeeze it back & forth & back & forth & yo=
u can visually see tension & compression phenomena happening at the same=
time</FONT></DIV>
<DIV><FONT size=3> Unless heat & pressure keep the felt from app=
roaching its elastic limit only so much density/compression can be achi=
eved in the middle of the hammer by strictly tension, which can be considera=
ble but not for the kind of hammers some prefer. I believe this is one =
reason why we've had so many bad sets of over hard hammers in the past. =
;Manufacturers have simply used heat or steam to densify felt & render i=
t's natural properties less or unusable. Hence steam voicing, excess needlin=
g, voice grips.</FONT></DIV>
<DIV><FONT size=3> We all want hammers that work the way intended &a=
mp; it seems that in many places its getting wwwaaayy closer. That's the way=
I see it</FONT></DIV>
<DIV><FONT size=3> WIllis, nice to hear your out there.<=
/FONT></DIV>
<DIV><FONT size=3> Regards</FONT></DIV>
<DIV><FONT size=3> Dale Erwin</FONT></DIV>
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<DIV> </DIV>
<DIV><FONT lang=0 face=Arial size=2 FAMILY="SANSSERIF" PTSIZE="10"=
>Erwins Pianos Restorations <BR>4721 Parker Rd.<BR>Modesto, Ca 95357<BR>209-=
577-8397<BR>Rebuilt Steinway , Mason &Hamlin Sales<BR>www.Erwinspiano.co=
m</FONT></DIV></BODY></HTML>