Your Guide to Buying Concrete Saw Blades
To ensure your concrete cuts are good, you need the right concrete saw blades. If you're looking for the best ones, here's your buying guide.
Since their invention in World War II, diamond saw blades have become the industry standard for concrete cutting. But with so many diamond concrete saw blades on the market, it can be hard to determine which one you should buy.
Here's a quick primer on concrete saw blades, and what questions you should ask yourself to ensure you're choosing the best blade for the job.
1. How Do Diamond Blades Work?
Understanding the basics of how diamond blades work will put you in a better position to choose the right blade for your needs.
The four basic diamond blade components are:
- The metal core: a steel disk with a segmented rim
- The synthetic diamond crystals: the teeth of the blade that cut through the concrete
- The matrix: the metal bond that holds the diamond crystals in place
- The weld: where the cutting segments attach to the core
The diamonds on the surface of the segmented rim do the actual cutting. As those diamonds are dulled through use, the matrix is designed to shed away, exposing new, sharper diamonds.
The hardness of the matrix will control how quickly a diamond blade wears.
2. What Sort of Concrete Are You Cutting?
Different blades are suited to different materials. Knowing what sort of concrete you're cutting will help you choose the best blade for the job and ensure you're getting the maximum use out of the blade.
The characteristics you need to take note of include:
Concrete that has a compressive strength of 3000 psi or lower is considered a soft material while 6000 psi or up is hard.
Blades with a hard matrix are best for soft material because it allows the diamonds to be fully utilized before wearing away.
A soft matrix is more suited to hard materials as the diamonds will dull faster. The faster the diamonds dull, the quicker they should be shed to expose new, sharper diamonds.
Size and Hardness of the Aggregate
The aggregate used will also impact on how quickly the blade wears. Hard aggregates such as basalt, quartz, or trap rock will cause a blade to wear more quickly so a blade with a soft matrix is more suited to the task.
The size of the aggregate used will also affect the blade performance. Aggregate 3/4 inches and up is considered large. A blade will cut and wear more slowly through large aggregate.
Aggregate smaller than 3/8 inches is easier to cut but the blade will wear faster.
Type of Sand
The type of sand used will determine the abrasiveness of the concrete. The more abrasive the sand, the harder the matrix of the blade should be.
3. When Are You Cutting It?
How soon you cut the concrete after placing it will also factor into your blade choice. Concrete is considered green about 1 to 2 hours after finishing and cured the day following once it's hardened completely.
Blades with a hard matrix are best for uncured, green concrete because the harder metal bond allows the exposed diamonds to be fully utilized before they're shed.
Cured concrete is best tackled with a blade with a softer matrix. The softer metal bond means the diamonds will be shed quicker, exposing the new, sharp diamonds as you need them.
Different Concrete Saw Blades for Different Jobs
There's no one-size-fits-all when it comes to concrete saw blades. The type of blade you're after will depend wholly on the job that needs doing.
Ready to get underway? Get in touch today and we'll help you match your job to the proper blade.