To design circular edges for shearing metal plates, and particularly, circular edges of large diameters into such a shape as facilitates as well as makes safe cutting edge replacement and sharpening work in repairs by sharpening required when their cutting edges wear out, and as eliminates a waste of material including their disposal in a still large-diameter condition, and design ordinary size circular edges for shearing metal plates with cutting edges of a costly material such as cemented carbide, on a simple and economical basis.

Disklike base metal 2 has an annular step 5 cut along the periphery at least in one surface to leave a disklike projected portion 9. A plurality of sectorial cutting edge tips 3 with an inner arc surface pressed against the circumference of the disklike projected portion 9 are screwed in annular relation about the disklike projected portion 9.