HOW TO PROPERLY DRESS A PLASTIC BONDED GRINDING WHEEL

Plastic bonded grinding wheels should be dressed differently than conventional (vitrified or resin bonded) wheels. Dress depths should be reduced (a good starting point is half the dress depth normally used).  Dresser traverse rates should be increased (usually 50% faster than the normal rate). The goal is to not close the Plastic Bonded wheel with a slow or deep dress.

Extensive grinding process analysis has revealed that plastic bonded wheels can be dulled by the dressing process. Dulling is magnified by deep or slow dresses. Usually the initial contact between a freshly dressed wheel and the work piece "conditions" the wheel to it's designed cutting structure.  

Much like the dressing process used with CBN (truing of the wheel followed by conditioning to expose the abrasive), plastic bonded wheels need to be tickled toward sharpness rather than crushed (like vitrified).  

The recommended changes to achieve a proper dress on a plastic bonded wheel are production enhancing:

SHALLOW DRESS = longer wheel life/reduced cost of grinding
FASTER DRESS = shorter cycle times/more parts ground per hour