The first diamond blades were invented by a man named Richard Felker during the World War II era. Called “Rimlock” blades, this chemist and pharmacist saw the ineffective metal blades being used for cutting tile and stone and believed there was a better way. When WWII began, Felker had developed several cutoff machines with blades that could handle cutting quartz frequency crystals used in radios and walkie-talkies in the war effort.
A diamond blade isn’t really a blade at all. While it does cut brick and stone, it’s more a grinding wheel than it is a blade; you can’t really cut yourself with it, but you can grind some meat off your foot or hand pretty quickly. When I have new guys working for me, I’d laugh when they’d tell me a blade wasn’t sharp anymore because it wasn’t cutting very well.
The way a diamond blade works is pretty much like a grinding wheel, too. Tiny bits of diamond are impregnated in a metal matrix at the outer edge of the blade. The exposed portion of the diamond is what does the cutting. As the diamonds are worn down, so is the metal matrix, allowing the spent diamond bits to be expelled from the blade, exposing new diamonds beneath to continue cutting.
In more recent years, significant development has been happening to make blades work more quickly and efficiently. One of the more important advancements in this area is improved air flow around the cutting surface and water cooling for portable saws. It’s too easy for masonry saw operators to get overly involved in the cutting of material and forget about allowing the blade to cool. This usually leads to premature blade wear, and big expenses for you. You’ll find more on the topic of blade choice in this section, and more about choosing blades that stay cooler while cutting.