I've been thinking about having a roller near the endmill to help hold down material.<div><br></div><div>Here's what I'm going to try. Anybody have any experience with this sort of thing or have any other ideas?</div>
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<div><br></div><div><span class="Apple-style-span" style="font-family: verdana, arial, sans-serif; font-size: 13px; line-height: 18px; "><div class="post-headline"><h2 style="margin-top: 0px; margin-bottom: 0px; padding-top: 0px; padding-bottom: 0px; padding-right: 0px; padding-left: 0px; margin-right: 0px; margin-left: 0px; font-size: 1.7em; ">
<a href="http://mambohead.com/2011/04/sheet-material-hold-down-on-cnc/" rel="bookmark" title="Permanent Link to Sheet material hold down on CNC" style="color: rgb(54, 93, 160); font-weight: bold; text-decoration: none; ">Sheet material hold down on CNC</a></h2>
</div><div class="post-byline" style="margin-top: 5px; margin-right: 0px; margin-bottom: 10px; margin-left: 0px; color: rgb(153, 153, 153); text-transform: uppercase; letter-spacing: 1px; font-size: 11px; ">BY DARCY WHYTE, ON APRIL 24TH, 2011</div>
<div class="post-bodycopy clearfix" style="min-width: 0px; display: block; "><div class="interactive_left" style="float: left; padding-top: 0px; padding-right: 10px; padding-bottom: 10px; padding-left: 0px; "></div><div id="attachment_3283" class="wp-caption alignright" style="float: right; margin-top: 10px; margin-right: 0px; margin-bottom: 5px; margin-left: 10px; max-width: 96%; height: auto; display: block; border-top-width: 1px; border-right-width: 1px; border-bottom-width: 1px; border-left-width: 1px; border-top-style: solid; border-right-style: solid; border-bottom-style: solid; border-left-style: solid; border-top-color: rgb(221, 221, 221); border-right-color: rgb(221, 221, 221); border-bottom-color: rgb(221, 221, 221); border-left-color: rgb(221, 221, 221); text-align: center; background-color: rgb(243, 243, 243); padding-top: 4px; border-top-left-radius: 3px 3px; border-top-right-radius: 3px 3px; border-bottom-right-radius: 3px 3px; border-bottom-left-radius: 3px 3px; width: 310px; ">
<a href="http://mambohead.com/wp-content/uploads/2011/04/rollerAssemble.jpg" style="color: rgb(54, 93, 160); font-weight: bold; text-decoration: none; "><img src="http://mambohead.com/wp-content/uploads/2011/04/rollerAssemble-300x244.jpg" alt="" title="rollerAssemble" width="300" height="244" class="size-medium wp-image-3283" style="border-top-width: 0px !important; border-right-width: 0px !important; border-bottom-width: 0px !important; border-left-width: 0px !important; border-style: initial; border-color: initial; padding-top: 0px !important; padding-right: 0px !important; padding-bottom: 0px !important; padding-left: 0px !important; border-top-style: none !important; border-right-style: none !important; border-bottom-style: none !important; border-left-style: none !important; background-color: rgb(243, 243, 243); border-top-left-radius: 3px 3px; border-top-right-radius: 3px 3px; border-bottom-right-radius: 3px 3px; border-bottom-left-radius: 3px 3px; margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; border-color: initial !important; "></a><p class="wp-caption-text" style="margin-top: 0px; margin-bottom: 0px; padding-top: 2px; padding-bottom: 5px; margin-right: 0px; margin-left: 0px; padding-right: 4px; padding-left: 4px; display: block; font-size: 0.8em; line-height: 13px; color: rgb(102, 102, 102); ">
roller</p></div>In ongoing issue with cutting cardboard is that it tends to be fairly floppy. You can clamp down its edges but the center often bulges away from the table.<p style="margin-top: 1em; margin-bottom: 1em; padding-top: 0px; padding-bottom: 0px; margin-right: 0px; margin-left: 0px; padding-right: 0px; padding-left: 0px; display: block; ">
</p><p style="margin-top: 1em; margin-bottom: 1em; padding-top: 0px; padding-bottom: 0px; margin-right: 0px; margin-left: 0px; padding-right: 0px; padding-left: 0px; display: block; ">Of course you can lord over the machine and help hold the material down.</p>
<p style="margin-top: 1em; margin-bottom: 1em; padding-top: 0px; padding-bottom: 0px; margin-right: 0px; margin-left: 0px; padding-right: 0px; padding-left: 0px; display: block; ">This problem happens when cutting a larger piece of hardboard as well. The endmill sometimes tries to lift the material up as it’s pulling material away from it.</p>
<p style="margin-top: 1em; margin-bottom: 1em; padding-top: 0px; padding-bottom: 0px; margin-right: 0px; margin-left: 0px; padding-right: 0px; padding-left: 0px; display: block; ">I thought of adding a small wheel to the cnc machine that can press down on the material being cut. So when the endmill plunges down, there will also be a wheel that comes down on the material.</p>
<p style="margin-top: 1em; margin-bottom: 1em; padding-top: 0px; padding-bottom: 0px; margin-right: 0px; margin-left: 0px; padding-right: 0px; padding-left: 0px; display: block; ">I thought it should be spring loaded and that it should be a castor so it will follow the direction of the cut.</p>
<p style="margin-top: 1em; margin-bottom: 1em; padding-top: 0px; padding-bottom: 0px; margin-right: 0px; margin-left: 0px; padding-right: 0px; padding-left: 0px; display: block; ">It may not be clear from the diagrams but I need to add some 1/4-20 threaded rod. Two pieces to form the axle for the wheel and the lever axis. Another vertical in the Square hole. A spring is running from the small holes at the lower right to the hole at the top right.</p>
<p style="margin-top: 1em; margin-bottom: 1em; padding-top: 0px; padding-bottom: 0px; margin-right: 0px; margin-left: 0px; padding-right: 0px; padding-left: 0px; display: block; ">I cooked this quick design up in Sketchup and will cut it out shortly and see if it works.<br>
</p><div id="gallery-1" class="gallery galleryid-3280" style="margin-top: auto; margin-right: auto; margin-bottom: auto; margin-left: auto; "><dl class="gallery-item" style="margin-top: 10px; margin-bottom: 10px; padding-top: 0px; padding-bottom: 0px; float: left; text-align: center; width: 250px; ">
<dt class="gallery-icon"><a href="http://mambohead.com/wp-content/uploads/2011/04/roller.jpg" title="roller" style="color: rgb(54, 93, 160); font-weight: bold; text-decoration: none; "><img width="150" height="150" src="http://mambohead.com/wp-content/uploads/2011/04/roller-150x150.jpg" class="attachment-thumbnail" alt="roller" title="roller" style="border-top-width: 2px; border-right-width: 2px; border-bottom-width: 2px; border-left-width: 2px; border-style: initial; border-color: initial; padding-top: 5px; padding-right: 5px; padding-bottom: 5px; padding-left: 5px; border-top-style: solid; border-right-style: solid; border-bottom-style: solid; border-left-style: solid; border-top-color: rgb(207, 207, 207); border-right-color: rgb(207, 207, 207); border-bottom-color: rgb(207, 207, 207); border-left-color: rgb(207, 207, 207); background-color: rgb(243, 243, 243); border-top-left-radius: 3px 3px; border-top-right-radius: 3px 3px; border-bottom-right-radius: 3px 3px; border-bottom-left-radius: 3px 3px; "></a></dt>
<dd class="gallery-caption" style="margin-left: 0px; ">roller</dd></dl><dl class="gallery-item" style="margin-top: 10px; margin-bottom: 10px; padding-top: 0px; padding-bottom: 0px; float: left; text-align: center; width: 250px; ">
<dt class="gallery-icon"><a href="http://mambohead.com/wp-content/uploads/2011/04/rollerAssemble.jpg" title="rollerAssemble" style="color: rgb(54, 93, 160); font-weight: bold; text-decoration: none; "><img width="150" height="150" src="http://mambohead.com/wp-content/uploads/2011/04/rollerAssemble-150x150.jpg" class="attachment-thumbnail" alt="roller" title="rollerAssemble" style="border-top-width: 2px; border-right-width: 2px; border-bottom-width: 2px; border-left-width: 2px; border-style: initial; border-color: initial; padding-top: 5px; padding-right: 5px; padding-bottom: 5px; padding-left: 5px; border-top-style: solid; border-right-style: solid; border-bottom-style: solid; border-left-style: solid; border-top-color: rgb(207, 207, 207); border-right-color: rgb(207, 207, 207); border-bottom-color: rgb(207, 207, 207); border-left-color: rgb(207, 207, 207); background-color: rgb(243, 243, 243); border-top-left-radius: 3px 3px; border-top-right-radius: 3px 3px; border-bottom-right-radius: 3px 3px; border-bottom-left-radius: 3px 3px; "></a></dt>
<dd class="gallery-caption" style="margin-left: 0px; ">roller</dd></dl><dl class="gallery-item" style="margin-top: 10px; margin-bottom: 10px; padding-top: 0px; padding-bottom: 0px; float: left; text-align: center; width: 250px; ">
<dt class="gallery-icon"><a href="http://mambohead.com/wp-content/uploads/2011/04/toolpath.jpg" title="toolpath" style="color: rgb(54, 93, 160); font-weight: bold; text-decoration: underline; "><img width="150" height="150" src="http://mambohead.com/wp-content/uploads/2011/04/toolpath-150x150.jpg" class="attachment-thumbnail" alt="toolpath" title="toolpath" style="border-top-width: 2px; border-right-width: 2px; border-bottom-width: 2px; border-left-width: 2px; border-style: initial; border-color: initial; padding-top: 5px; padding-right: 5px; padding-bottom: 5px; padding-left: 5px; border-top-style: solid; border-right-style: solid; border-bottom-style: solid; border-left-style: solid; border-top-color: rgb(207, 207, 207); border-right-color: rgb(207, 207, 207); border-bottom-color: rgb(207, 207, 207); border-left-color: rgb(207, 207, 207); background-color: rgb(243, 243, 243); border-top-left-radius: 3px 3px; border-top-right-radius: 3px 3px; border-bottom-right-radius: 3px 3px; border-bottom-left-radius: 3px 3px; "></a></dt>
</dl></div></div></span></div></div>