Get the Bessey right angle clamp at Amazon, The Home Depot, Ace Hardware, Woodcraft, or Rockler. ... Those with L brackets will have a clamp on each arm of the L shape.

PEM R'ANGLE fasteners from PennEngineering Fastening Technologies, Danboro, Pa., includes both self-tapping and steel-threaded types, which install permanently in metal sheets as thin as 0.040 in ...