These innovative blades will remain flexible and retain their sharpness much longer than the average cold knife blade. The grinding of the blade is at a greater angle than other cold knife blades. This makes the resistance less when pulling the cold knife to cut the urethane. The end result is a cold knife blade that has the ability to resist breaking, last longer, and keep a sharp edge. Equalizer produces two types of cold knife blades. Both the standard and the coined blades use the same proprietary hardening process.
The Coined Z Blade... The cutting surface of a coined cold knife blade has the cutting surface of the blade made thinner, only about 35 thousandths of an inch thick. A normal cold knife blade is 62 thousandths thick. Many technicians routinely grind cold knife blades thinner so they will cut easier. Sometimes this grinding will overheat a blade and damage the hardening. Coined Z blades are thinned before they are hardened so there is no need to grind them thinner.
Should I buy coined or not coined blades?
If you use a cold knife blade right out of the box and never grind it thinner, then use the standard thickness Z1, Z2, Z3, or Z7. If you like to take a new blade and grind it thinner before you use it, then you should purchase the "pre-thinned" Z4, Z5, Z6, or Z8.