Note: Take proper safety precautions when working with heads, knives and other tools.
Replace the stock knife rest insert with the SuperHelic knife rest insert. (Global P/N: GP100-HTR)
We recommend using a diamond grinding wheel (Global P/N: GW9302) with a 3mm thickness and 1.5mm radius although other thicknesses of diamond wheels may be used as long as they have a radius.
Center the point on the knife rest with the diamond wheel by either moving the knife rest insert or shimming the grinding wheel. The knife rest must be centered for the grinding of either right or left hand helix.
Set the back clearance angle on the grinder to 11°. Turn on the grinding wheel and move the wheel up until it just touches the knife rest. Grind a slight groove into the rest until the wheel is 0.040” to 0.050” from the front face of the knife rest. Move the wheel back 0.005” to 0.010” until the wheel is no longer grinding.
Mount the cutter head on the grinder. Use gloves to protect your hands.
Line up the end of the helical knife to sit on the point of the knife rest. Remove 0.003” to 0.005”from the knife with each grinding pass. The helical head will twist as you move from right to left sharpening the knife. Be sure to use down pressure to prevent the knife from lifting off the tool rest as the helical head twists/rotates around the helix. Sharpen equal amounts off each knife. Reset “0” to maintain cutting concentricity. Grind each knife once and then inspect to determine if additional passes are required.
The grinding wheel must not contact the head body. The knives can be extended out of the body by moving up a corrugation if needed.