I needed to make a couple of long mitre joints for a back-drop panel. So I marked pencil lines on both sides and opposite sides of the panel. I covered the lines with two layers of tape. The tape will act like a hinge.
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I took a 60-degree V-Bit and routed along the line, right down to, but not through, the double layer of tape. I took more than one pass. You can, of course, do this with 90-degree bits as well.
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then ran two small beads of adhesive along the length of the grooves.
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folded and held the fold in place with a few passes of hotmelt.
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the glue dries, I will paint. A quick scuff of a sanding block will make the mitre seam smooth enough to paint without having to fill any gaps.
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