<!doctype html public "-//W3C//DTD W3 HTML//EN"> <html><head><style type="text/css"></style><title>Downbearing - Setting with a loose board</title></head><body> <blockquote type="cite" cite> <blockquote type="cite" cite>Someone else suggested temporarily screwing the soundboard down to the rim - I like that idea.</blockquote> </blockquote> <blockquote type="cite" cite><br> That's what I do too. The plate, treble cap, and damper guide rails cover the holes afterward.<br> </blockquote> <blockquote type="cite" cite>Ron N</blockquote> <div><br></div> <div>Same here also. We use the Baldwin plate mounting system, so the original inner-rim bolts holes are plugged before the sound board is fitted. This allows us to screw the board down at the perimeter-bolt locations. This is similar to Dale's idea of screwing the board down where the plate height dowels will be fitted. Along the bass side our sound board installation clamps are used, and along the cut-off standard clamps can be used since our sound board panel doesn't cover the corner.</div> <div><br></div> <div>The plate height, at the rear, is set initially by placing a wooden block between the loose board and the plate. The board can be either screwed in with screws, or the perimeter bolts<font color="#0000FF"> (which have been converted to thread into the plate, by fitting threaded inserts into the original plate holes)</font> can be screwed down to the loose board to hold it in place. To establish the new bridge heights, we use a series of in-house manufactured blocks, with a cap screw<font color="#0000FF"> (threaded into the top face of the block)</font> for height adjustment. Using four blocks per string section<font color="#0000FF"> (first note, last and two intermediates)</font>, the blocks are positioned so that the cap screw head is located where the speaking length termination will be for the new bridge.</div> <div><br></div> <div>A nominal stringing-pillow height is assigned to each sample note prior to setting the height of the adjustable blocks. These stringing pillow heights are varied slightly to fine tune the downbearing before the piano is strung.</div> <div><br></div> <div>We don't wedge the board down to pre-load it prior to setting the bridge height/down bearing. Since the downbearing loads are quantifiable, it is possible to predict the sound board drop when under load. The desired final down bearing angle, and the loss of angle predicted under down bearing load are added together to arrive at an unstrung initial down bearing setting for each point.</div> <div><br></div> <div>Ron O.</div> <div><br></div> <x-sigsep><pre>-- </pre></x-sigsep> <div><font face="Times" size="-2" color="#000000"><br></font></div> <div><font face="Times" size="+1" color="#0000FF"><b>OVERS PIANOS - SYDNEY</b></font></div> <div><font face="Times" color="#0000FF"><i>  Grand piano manufacturers</i></font></div> <div><font color="#000000">________________________</font><br> <font color="#000000"></font></div> <div><font face="Times" color="#000000">Web:    http://www.overspianos.com.au</font></div> <div><font face="Times" color="#000000">Email: mailto:ron@overspianos.com.au</font><font color="#000000"><br> ________________________</font></div> </body> </html>