Place material to be nibbled in the gap between the punch and blade channel. Squeeze the handles together. Punch will move down into channel, cutting out a slug of metal.
A scribe line can be followed from this position. Continue cutting to create a slot.
To make a 90° corner, pull tool out of slot, turn the work 90°, and insert the tool again.
By turning the tool before each cut, a 5/16" (7.9mm) minimum radius can be cut.
Almost any size or shape of hole can be cut by starting with a 3/8" (9.5mm) hole.