I made my last tantern 6 sided with a cross cut out of each pannel
I did n=mine out of scrap about 18 ga.
Made one pattern and copied it so there were 6 sides
Glued this to the sheet and pierced the material with chisels and a treadle hammer making sure not to cut all the way through antil at least the 3rd or 4th pass with the chisel.
A chiesel cut leaves a beveled edge that should be cleaned up with files but gives the hand made look not cut out vith a plasma or laser.
I scored on the inside a line with the chisel for a place to bend and left a tab to rivet the finished piece together.
If 6 sided each bend will be 60 degrees
Roger in Minnesota, usa