Repair of a Cracked Plate in a 1902 Bosendorfer Grand Piano.

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=90 BGCOLOR="#006699" TEXT="#080000" background="045fd5a3.jpg"> <div> <B> Repair of a Cracked Plate in a 1902 Bosendorfer Grand Piano.</B></div> <div> </div> </td> </tr><tr> <td valign="top" width=210 BGCOLOR="#FFCC66" TEXT="#080000" background="046d2b03.jpg"> <bR> <div> <A HREF="index.htm" TARGET="_top" TITLE="Murrays Piano Service "><U><B>Home</B></U></A></div> <div> <A HREF="id176.htm" TARGET="_top" TITLE="1902 Bosendorfer 6 10 Grand Piano Rebuil"><U><B>Back To Bosendorfer Rebuild</B></U></A></div> </td> <td valign="top" height=390 BGCOLOR="#FFFFFF" TEXT="#080000" bgproperties="fixed" background="090ab813.jpg"> <div> <TABLE BORDER="2" CELLPADDING="2" CELLSPACING="1" WIDTH="608" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 19 WIDTH="596"><div> <I><B>Scroll Down, Lots of Photos</B></I><I><B> <A NAME="plate_photos"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="1" ALIGN="bottom" WIDTH="1" HSPACE="0" VSPACE="0" ></A></B></I></div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2d658c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 19 ><NOBR><div> During disassembly a crack was discovered in the cast iron plate.</div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2d758c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="596"><div> A proper repair is critical. The treble section will never be able to be tuned because of the location of the crack in the pin block flange.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2d858c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2d958c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 172 WIDTH="596"><div> Lock n Stitch in Turlock, CA was employed to repair the cast iron plate. Cast iron is very difficult to weld, the entire plate must be heated to perhaps 1500 degrees Fahrenheit to sync the plate to the welding process, even with heat syncing, the plate can still become unstable and change shape or crack in a different location because of the stresses imparted in the welding process.  For that reason metal braiding, or metal stitching was my preferred method, not welding. As I was not willing to let this valuable customer piano plate out of my possession, I personally trucked it over to Lock n Stitch and photographed the following sequence. </div> <div> Above the first of many 'locking bolts' have been installed.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2da58c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="596"><div> Here a second is being drilled. The threads are patented and pull the surrounding metal together.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2db58c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="596"><div> The hole is then taped for the threads. All components including taps are made in house by Lock n Stitch.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2dc58c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 19 ><NOBR><div> Here is their counter sink. It's shape further pulls the surrounding metal together.</div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2dd58c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 19 WIDTH="596"><div> Locking bolt being inserted.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2de58c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2df58c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 19 WIDTH="596"><div> And turned into place.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e058c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 19 WIDTH="596"><div> The bolt is touqued down until the head shears off.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e158c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 19 WIDTH="596"><div> Remaining bolt head is ground flush.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e258c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e358c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e458c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e558c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 19 ><NOBR><div> A bigger stitching bolt is used as a dowel for reinforcement.</div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e658c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e758c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="596"><div> The process continues until the crack is completely filled with locking bolts each ground down and the metal worked and layed out to blend with the surrounding area.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e858c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 456 ><NOBR><div> <IMG SRC="2e958c20.jpg" border=0 width="600" height="450" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="596"><div> The above 2 photos show the finished product. The plate will be completely refinished with bronzing powders later.  <FONT SIZE="3" COLOR="#0000BF" FACE="Arial" ><A HREF="#plate_photos" TITLE=" Repair of a Cracked Plate in a 1902 Bos"><U> To Top</U></A></FONT></div> </tD> </tR> </TABLE></div> <bR> </td> </tr></table></body>