Diamond Blades, Concrete Cutting:

Selecting the right diamond blade to run on concrete saws is the best way to maximize your equipment investment. More and mare companies offer diamond blades. But how can a contractor choose the right blade for the right saw?

How diamond saws cut
Blade performance is a combination of the material being cut, cutting speed and blade life. Changing one variable affects the others. Aggregate hardness and size, amount of steel reinforcing (rebar) and whether the concrete is green or cured affects blade selection. The diamond blade segments are made up of a mixture of diamonds and metal powders. The composition of the bond that holds the diamonds must be matched to the hardness or softness of the material being cut. The simple rule of thumb to remember when selecting a blade: Use something hard to cut something soft and something soft to cut something hard.

Know your concrete
The size of the aggregate affects blade performance. Large aggregate makes the blade cut slower, while smaller aggregate makes the blade cut faster. Heavy reinforcing with rebar also tends to slow the blade and make it wear faster. The time the concrete has had to cure greatly affects how the material will interact with the blade. Freshly poured or green concrete is softer and more abrasive than cured concrete. The blade will need a harder bond with undercut protection to cut green concrete and a softer bond for cured concrete. Undercutting is a condition in which the steel core of the blade wears faster than the diamond segments. It is caused by highly abrasive material grinding against the core. The best remedy is to choose a blade with under-cut protectors on the core or pol-yarc segments.