I roll bezels out of wire stock, or I saw them, or I use some big
sheet metal shears from the hardware store. Big shears wiggle around
less than little ones. But none of these results in a very flat
In shaping the bezel on a mandrel, the crimp from the shears comes
out and it gets a little work hardened. Then, you can rub it across
some wet or dry sand paper to true up the edge to be soldered.
Later, you can file the top edge when you prepare to set the stone.
The shape is stable because it is soldered onto your jewelry - or
stuck in shellac. Then, you can adjust the height and finish that
edge with a rubber wheel.