I want to make some short pieces of tubing for setting round stone on the surface of rings and pendants. I would use rounds of about 3-7mm and tubing formed from approx. 20 gauge silver (0.7 to 0.8mm) or slightly larger. I watched a video on making short lengths of tubing:
Basically the procedure is to compute the width of sheet needed and use a length of 15 to 25mm of sheet. Round up the sheet gradually with needle nose pliers and eventually by using a small round mandrel set in a halfround (U channel) swaging block hit with a small chasing hammer to round it out, then soldering the tube closed, filing the join and re-rounding it again with the mandrel and hammer. Then, of course, cut the height needed for the bezel off the tubing…you’d get several bezels out of one piece of 15 to 25mm length. This took a while, but seemed OK…however, when I looked for a swage block that would work, the only ones around $40 had channels that really weren’t a complete half circle. I don’t know how well these would work, so I need some feedback on that.
Another way to proceed would be to bend the sheet by hammering it on a series of smaller and smaller dowels or round mandrels until it is about half closed and then pull it through a draw plate to round it. I found a video of this process, but it used thin fine silver. I did find a decent draw plate with holes from about 3 mm to 10mm that looked like it would work, but I don't know whether it will be possible to pull a halfway rounded up 20 gauge sheet thru the various holes in a draw plate to get to a 3 to 7mm tube. The draw plate is about $40. So I'd like some feedback on which process would work best...would one of those swage blocks that seem to only round up about 90 degrees of a circle work OK, or would I really do better with the Durston one that is $150? Or would drawing the sheet thru a drawplate, which seems easier and quicker work for my 18 t0 20 gauge sheet? Surely some of you have been thru this, right?