I found by cutting wedge shapes I could get more parts. This sheet would yeild 4 parts cutting rectangles, or 5 parts cutting wedges.
I marked the sheet by laying the forms on it and offsetting from the edge 20mm. Then I used a straight edge and offset it 20mm and marked lines for the shear cuts.
A little trick is to notch the metal down with snips so is will catch on the shear edge when you push/pull the metal through the shear. No backgage is necessary.
Layed out and cut 6 wing ribs tonight. Clamped each form down, transfered hole locations, marked form ends to finish layout for trim relief, then offset a line 18mm around the whole form. Unclampped the form and finished the layout for the ends including centers for the 3/16" refief holes. Punched the relief holes in all 6 parts. Then I use the Malco snips and trimmed all the parts. Put in the 1/4" holes for the centers of the lightening holes then finished up by using the belt sander along the edge to smooth the surface and remove burrs.
