HI
You can pickup a Porter Cable box joint finger template ONLY screw it to some timber and than clamp it to the edge of 20" x 40" board ,than put the bit in the router and put the slots in place.. the Porter Cable template is 32" long and can be had at Amazon or from any dealer that's sales PC items..
http://www.routerforums.com/show-n-tell/3264-perfect-box-joints.html
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You can pickup a Porter Cable box joint finger template ONLY screw it to some timber and than clamp it to the edge of 20" x 40" board ,than put the bit in the router and put the slots in place.. the Porter Cable template is 32" long and can be had at Amazon or from any dealer that's sales PC items..
http://www.routerforums.com/show-n-tell/3264-perfect-box-joints.html
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