One option for framing, especially where the edges are not rectangular is to use lead. The lead touching the glass or copper foiled edge should be 10mm flat came. This allows you to insert a 5mm mild steel rod shaped to the outside of the panel. This is then covered by a 13mm flat came. The came is smoothed by gentle pressure on the upper and lower flanges with a stopping or lead knife to bring the two flanges together. This gives a pleasant finish to the edge.
by Gene Mallard