O.K. Here we go, this is the way I would tackle it. In fact two contributors have suggested the answer. I have only combined the two.
First I would use ‘oilcans’ method with the difference that I would cut two pieces of 1/4″ thick mild steel at an angle of say 60 deg, sandwich the metal to be bent between them. This needs to be with the straight portion of the bar aligned with the top edge of the plough share so that the angle crosses the share blade, the tip of the angle probably needs to be 1 1/2″ to 2″ up from the base. The reason for this is that the 1.5mm plate will want to turn about its own centre line. By the way make sure you clamp the tips of the angle with toolmakers clamps. Then bend away, you will probably need to bend through 100 deg as the material will want to spring back, in stainless this will be even worse.
Now MGJ suggests a hard wood former, having got the basic shape, with the hardwood former and a few taps with a hammer you should have something which looks like your plough share. These should all look the same. There will need to be a bit of trial and error and as MGJ says have a go with some alli.
Best of luck, please let us know how you get on.
Edited By Dusty on 20/04/2011 09:23:59