Principles of Curve Sawing

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0 height="100%"><tr> <td valign="top" width=200 BGCOLOR="#FFFFFF" TEXT="#080000" background="0dac8c00egerdp.jpg"> <div> <IMG SRC="0be6e3d0.jpg" border=0 width="110" height="61" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> <TABLE BORDER="4" CELLPADDING="2" CELLSPACING="1" WIDTH="112" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" BGCOLOR=#009900 > <tR> <tD VALIGN=TOP BGCOLOR=#FFFFFF HEIGHT= 14 WIDTH="96"><div> <B>PRODUCTS</B></div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 28 WIDTH="96"><div> <A HREF="id27.htm" TARGET="_top" TITLE="Frame Saw Technology"><U><B>Frame Saw Technology</B></U></A></div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 28 WIDTH="96"><div> <A HREF="id26.htm" TARGET="_top" TITLE="Band Saw Technology"><U><B>Band Saw Technology</B></U></A></div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 28 WIDTH="96"><div> <A HREF="id33.htm" TARGET="_top" TITLE="Edger Technology"><U><B>Edger Technology</B></U></A></div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 28 WIDTH="96"><div> <A HREF="id24.htm" TARGET="_top" TITLE="Circular Saw Technology"><U><B>Circular Saw Technology</B></U></A></div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 28 WIDTH="96"><div> <A HREF="id23.htm" TARGET="_top" TITLE="Chipper Canter Technology"><U><B>Chipper Canter Technology</B></U></A></div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 28 WIDTH="96"><div> <A HREF="id25.htm" TARGET="_top" TITLE="Profiling Technology"><U><B>Profiling Technology</B></U></A></div> </tD> </tR> </TABLE></div> <div> <TABLE BORDER="4" CELLPADDING="2" CELLSPACING="1" WIDTH="112" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" BGCOLOR=#009933 > <tR> <tD VALIGN=TOP BGCOLOR=#FFFFFF HEIGHT= 14 ><NOBR><div> <B>CURVE SAWING</B></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 14 WIDTH="96"><div> <A HREF="id52.htm" TARGET="_top" TITLE="Principles of Curve Sawing"><U><B>Principles</B></U></A></div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 14 WIDTH="96"><div> <A HREF="id50.htm" TARGET="_top" TITLE="Curve Sawing vs Straight Sawing"><U><B>Comparison</B></U></A></div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 14 ><NOBR><div> <A HREF="id54.htm" TARGET="_top" TITLE="Sample Sash Gang Layout"><U><B>Sample Layout</B></U></A></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#FFFF00 HEIGHT= 14 WIDTH="96"><div> <A HREF="id55.htm" TARGET="_top" TITLE="Infeed Table Details"><U><B>Infeed Table</B></U></A></div> </tD> </tR> </TABLE></div> <bR> </td> <td valign="top" BGCOLOR="#FFFFFF" TEXT="#080000"> <div>  <FONT SIZE="5" COLOR="#339933" FACE="Arial" ><IMG SRC="188bb9a0.jpg" border=0 width="443" height="154" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></FONT></div> <div> <A HREF="index.htm" TARGET="_top" TITLE="www.sawingtechnology.com Koenig Sawmill "><U><IMG SRC="1896e260.jpg" border=0 width="110" height="38" ALT="Home" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A><A HREF="id31.htm" TARGET="_top" TITLE="About Us"><U><IMG SRC="18a6e260.jpg" border=0 width="110" height="38" ALT="About Us" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A><A HREF="id30.htm" TARGET="_top" TITLE="News"><U><IMG SRC="18b6e260.jpg" border=0 width="110" height="38" ALT="News" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A><A HREF="id19.htm" TARGET="_top" TITLE="Contact Us"><U><IMG SRC="18c6e260.jpg" border=0 width="110" height="38" ALT="Contact Us" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A><A HREF="id20.htm" TARGET="_top" TITLE="Our Products and Services"><U><IMG SRC="18d6e260.jpg" border=0 width="110" height="38" ALT="Our Products and Services" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A><A HREF="id28.htm" TARGET="_top" TITLE="Other Partners"><U><IMG SRC="18e6e260.jpg" border=0 width="110" height="38" ALT="Other Partners" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <div> Principles of Curve Sawing</div> <div> <I><B>Curve (sweep) Sawing with Sash Gang Saw and Infeed Table</B></I></div> <div> While straight sawing, a sash gang saw's top and bottom feed rollers feed a timber linearly along the same axis in which it is fed.  Thus, only the center boards of a curved log can be recovered.  Curve sawing allows maximum recovery of a log by following its contour.  To follow the curve of a log, the infeed table utilizes (2) side shifting and independently pivoting holdover arms.   One holdover arm functions as a line-bar (lined up straight), while the other pivots in and holds the log against the line-bar.  Therefore, the log sweeps through the sash gang saw.   </div> <bR> <div> <B>Infeed table function:</B></div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Cross-conveyed logs brought to the infeed table's air lifted/lowered jump-chains that bring each log to the centerline, or skew it as necessary.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">With the jump-chains lowered, the gear-motor-driven feed rollers feed each log toward the sash gang saw.  Feeding is also reversible.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The hold-over arms can side-shift laterally and align each log to the ideal cutting position.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Once the log is started in between the sash gang infeed rollers, the pivoting hold-over arm holds the log against the straight pivot arm so that the log will be curve sawn.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Depending on the curvature of a log, the hold-over arms pivot and feed either to the left or to the right.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The straight line-bar guide equalizes extremities, so that each knot and extrusion aren't followed.</div> <bR> <div> <B>Advantages:</B></div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Gain on recovery for yellow pine averages 15%.  Mill output also increases.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Sash Gang can saw 2-sided cants (flitches) or round logs.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Sash Gang easily handles sweep of 8” and more for cants and logs.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Sawblades are under high tension in tooth area and soft in rear. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Jigsawing effect of sash gang saw allows to follow sweep in small increments per stroke (320/min.).</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Width of sawblades is only 4-7”; saws don't heat up any more than during straight cuts.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Once timber reaches the saws and linebars are set, sweep of timber is sawn automatically without dependence on operator.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Gain of 15% can be reached without big investment; without electronics or computers; only simple mechanical design on the infeed table is necessary.  Maintenance is also a fraction of the high-speed, million-dollar systems.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Each board sawn still has the high quality and precision of the typical sash gang saw cut.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Besides recovery, gain also on in grade because the cut stays between the grain - less grain cross-cutting.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Sweep sawn boards flatten-out easier during drying.  Grain cross-cut boards tend to twist.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800330000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Conveying boards up to 2” pose no problem, even on sling sorters.</div> <bR> </td> </tr></table></body>