<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=US-ASCII"> <META content="MSHTML 6.00.2900.2523" name=GENERATOR></HEAD> <BODY id=role_body style="FONT-SIZE: 10pt; COLOR: #000000; FONT-FAMILY: = Arial" bottomMargin=7 leftMargin=7 topMargin=7 rightMargin=7><FONT id=rol= e_document face=Arial color=#000000 size=2> <DIV> <DIV>    <STRONG><FONT size=3>Hi Clyde</FONT></STRONG></DIV= > <DIV><STRONG><FONT size=3>   The real pioneers of this technolog= y if I'm correct  rightly goes to folks such as Del Fandrich,Ron Overs in Australia &  Ron Nossaman from the great state of Kansas.&nbsp= ; What these guys have learned  they've freely shared on this list f= or many years& I'm simply along for an interesting  journey in so= und production thanks to them.</FONT></STRONG></DIV> <DIV><FONT size=3><STRONG>  The cut off bars & fish are essential= ly mechanical ways to increase soundboard crown reliability , longevity </STRONG> <STRONG>& enhancing mechanical impedance. = By Adding a bass cutoff bar the bridge is sitting more in the center of & o= n the highest part of the rib/crowmn.. Shortening the rib obviously  make= s it stiffer. Crowning the ribs & making them taller & less wide also aid= s this. </STRONG></FONT></DIV> <DIV><STRONG><FONT size=3>  I rebuilt A 1905 Bluethner 6 ft grand tha= t had a beautiful sweeping cutoff bar but the ribs had no height/depth  consequently  no crown. So cutoffs are not new but they are being incorporated with other design features these days such as taller & narr= ower ribs to support crown instead of to much destructive Panel compression.= </FONT></STRONG></DIV> <DIV><STRONG><FONT size=3>  I really feel like the ones who should be= explaining this should be the brothers mentioned above. Also the archives ar= e full of this.</FONT></STRONG></DIV> <DIV><STRONG><FONT size=3>  Check out WWW. Ron Overs Or Del Fandrich Northwest piano Builders. Also Terry Farrel is making component part for the= trade such as custom one off cut off bars.</FONT></STRONG></DIV> <DIV><STRONG><FONT size=3>  Some of this work is math, science & educating guessing & plain common sense.</FONT></STRONG></DIV> <DIV><STRONG><FONT size=3> At any rate I'm glad it's got your interest.</FONT></STRONG></DIV> <DIV><STRONG><FONT size=3>  Regards</FONT></STRONG></DIV> <DIV><STRONG><FONT size=3>  Dale</FONT></STRONG></DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><= FONT style="BACKGROUND-COLOR: transparent" face=Arial color=#000000> <DIV>Dale,</DIV> <DIV>This work you are doing to enhance the performance of re-build projects is very amazing. Adding cutoff bars and "fish" (which I supp= ose is the equivalent to a cutoff bar for the high treble) is very interesting= . Would you share how to calculate the positioning of the cutoff bar and fis= h. I suppose (and perhaps wrongly so) that the cutoff bars positioning is a function of the soundboards area and rib lengths? What is the correct way = to determine the cutoffs positioning? and how do you arrive at the dimensions= and positioning for the fish? Thanks in advance for your help in this matter. = I've just been going through the pictures you posted and find this fascinating!</DIV> <DIV> </DIV> <DIV>Clyde Allen</DIV> <DIV>PTG Assoc.</DIV> <DIV>Silver Spring, MD</DIV> <DIV><BR><B><I>Erwinspiano@aol.com</I></B> wrote:</DIV> <BLOCKQUOTE class=replbq style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px sol= id"><BR>     Too All<BR>     The pictures show a added cut off ba= r I posted about last week <BR>which was recycled from the baldwin upright. = I decided to add the fish <BR>in the treble after Terry posted his pictures & alos because of input <BR>from many other rebuilders on list that have discussed more modern <BR>approaches to developing sustain & power in conjunction with sound <BR>board crown= longevity.<BR>  As posted previously the ribs on this piano are extremely long & <BR>would have provided inadequate crown support. A= lso the ribs & <BR>soundboard area in the top treble were extremely gene= rous to the point <BR>of sacrificing stiffness required for adequate impedanc= e. I'm changing <BR>all the tri-chords top bichords & probaly a bass br= idge change too.<BR>  The jury's still out tonally. I'll! report back wh= en its strung. The <BR>action is already to go so in march I'll tell "The r= est of the story" <BR>We pressed the board today, the block is made  as= seen in picture.<BR>   Dale Erwin<BR> <BR>[Photos at:]<BR><BR>http://tinyurl.com/3jmod<BR><BR>http://tinyurl.com/4y95u<BR>= <BR>http://tinyurl.com/48ztm<BR><BR>http://tinyurl.com/5fmsb<BR><BR>http://t= inyurl.com/6yron<BR><BR><BR>[Direct ptg.org URLs:]<BR><BR>https://www.moypiano.com/ptg/files/attachments/f5/86/c0/a5= /DSCN4569.JPG<BR><BR>https://www.moypiano.com/ptg/files/attachments/5e/16/2e= /fb/DSCN4570.JPG<BR><BR>https://www.moypiano.com/ptg/files/attachments/6f/92= /1c/64/DSCN4571.JPG<BR><BR>https://www.moypiano.com/ptg/files/attachments/c2= /6c/44/4a/DSCN4572.JPG<BR><BR>https://www.moypiano.com/ptg/files/attachments= /45/2c/31/4a/DSCN4573.JPG<BR><BR><BR><BR> <BR>Erwins Pianos Restorations<BR>4721 Parker Rd.<BR>Modesto, Ca 95357<BR>209-577-8397<BR>Rebuilt Steinway , Mason &Hamlin Sales<BR>www.Erwinspiano.com<BR>________________________________________= _______</BLOCKQUOTE></FONT></BLOCKQUOTE></DIV> <DIV></DIV> <DIV> </DIV></FONT></BODY></HTML>