A steel form was made the same shape as the opening in the heat extractor and welded to the workbench. Next, some welding rod was formed around the form to shape the rod into a frame for the grille.
The Spitznagel Maxi dent pulling resistance welder was used to zap the grilles to their frames.
A small amount of current is all it takes to cleanly melt the wires together.
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