Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <BillEaver-at-aol-dot-com> To the one making flat plate caps with Al sheets.(The one with the impossible name for a screen name.) Make sure you trim the corners smooth and round off each plate. If not, your cap will suffer arcing from these points. Hope this helps. Denis Despins KC6TRW