To properly regrind thin edge knives, one must have:
Soft wheels of the proper grit and grade. Alcon uses the following wheels:
7" x 1/2" x 1 1/4" 32A60 H 8VBE 3500 RPM
8" Cup wheels 32A46 G 8VBE 1800 RPM
An understanding of the edge one hopes to obtain. When knife edges are of an included angle of 15º or over, they can be finish ground in one set-up on each side. When the included angle is less than 15º, it is necessary to use a sharpening bevel as shown in the sketches illustrated to the left.
When knife edges are ground paper thin, the material is embrittled and the edge will chip off. It is important that the edge at the back of the sharpening bevel be ground to not less than .008". If a thinner edge is required, it must be obtained by honing.
Proper back up plates, especially if there is any time limit on the work.
For single bevel knives, the back-up plate is flat.
For double bevel knives the plate must be a cup to support the rim; for otherwise the knife will deflect away from the wheel and the edge may be cracked or broken off by the distortion.
All new knives are supported in this manner and an overhang of over 1/32" cannot be permitted.