Can Diamond Blades Cut Metal? Everything You Need to Know!
Why Use Diamond Blades?
In today’s modern day and age, structures and buildings are often built and with the likes of concrete and other hard metals.
These materials aren’t easy to cut.
You can’t just grab any regular old saw…
Hard materials need to be cut with an even tougher and stronger material.
That’s where diamond comes in.
Diamond, if you don’t know already, is the hardest naturally occurring substance known to man, which is why it’s used to cut hard materials like tile, steel, and concrete.
On the mineral hardness scale, diamond comes out on top, have a rating of 10 on the Mohs Hardness scale.
But diamonds are also pretty rare, making them rather pricey.
So when you buy a diamond blade, the blade is actually synthetic (man-made) diamond.
Without a synthetic diamond, it would be virtually impossible to cut hard materials…
These blades also offer multiple advantages over other metal and abrasive blades:
Safer to Use
Last Much Longer
Cut Much Faster
Will Diamond Blades Cut Metal?
Yes, certain diamond blades can cut through metal, but this will depend entirely on the blades application.
Most diamond blades are used to cut through concrete, brick, tile, and asphalt.
But, not all blades are the same.
Different blades mean different applications…
Each blade comes with a different styles, shape, and grooves which come into play in it’s ability to cut.
Usually, each blade is specialized to cut a certain material or hardness of materials.
Take for example, the difference in concrete vs asphalt diamond blades.
“Because asphalt is softer than surfaces like concrete, or granite, soft bonded blades won’t be effective and typically don’t result in clean cuts. Instead, the best tool for asphalt cutting is a diamond blade with a hard bond.”
Some blades are universal and can be used to cut through almost all materials.
Before buying any blade, always be sure to do your research and figure out it’s application.
Check the product packaging. If you’re not sure, ask someone for help in identifying the application/specialization.
Can Diamond Blades Cut Steel?
Steel is one of the strongest metals on the planet.
When it comes to diamond blades, there are a few that can cut through steel.
Certain blades like the Husqvarna High Pro 3 and 5 series are acceptable for cutting through steel bars.
But in general, abrasive saws are betting for cutting steel, not diamond.
Abrasive saws are made of “aluminum oxide grain that is reinforced with two sheets of fiberglass or other insulting material” which is better for grinding through steel.
How do Diamond Blades Cut?
Believe it or not, but diamond blades don’t actually cut.
Instead, they use the friction force to ‘grind’ away at the material.
“Harder materials are best cut when the bond of the diamond blade is softer. As the diamond particles are dulled and broken, the bond releases so that more of the synthetic diamond can be exposed grinding away at the material.”
“The reverse is true for cutting softer materials. The bond is stronger to ensure that the diamond is exposed long enough to be fully utilized.”
Essentially, the blades scratches away at the particles of each material.
What Size Diamond Blade Should I Choose?
Size of the blade will also have an impact on what your cutting and the project your working on.
You’re not going to walk into the kitchen to cut some tile with a 30″ diamond blade and a massive cut off saw. You’ll probably use a much smaller, electric saw with a more applicable 4″ blade.
Keep this in mind next time you begin a home renovation project.
The size you choose will depend on the sizing that fits your saw.
In order to find this out, read the saws manufacturers manual or product packaging and find out the diameter of the blade it takes.
How Long do Diamond Blades Last?
It depends.
The material you’re cutting and the usage will be the greatest determinants of your blades life expectancy.
That being said, it’s generally known that a diamond blade can be used about 100 times longer than other abrasive type blades.
The quality of the blade will also play a factor:
Low Quality Blades Will Last for Around 10 Hours of Total Cutting Time
Higher Quality Blades Have a Lifespan of up to 120 Hours or Even More of Cutting Time
Remember, buying cheap is often more expensive in the long run.
Diamond Blade and Saw Safety Tips
Any blade and saw is dangerous.
Saws spin at a couple thousand Revolutions Per Minute (RPM). Combine that with the fact the blade is made of the hardest material on earth and you have a pretty serious cutting machine.
There’s no way you want your hand or any other body part anywhere near that blade…
Here are a few tips to keep you safe out there:
Wear the Proper Safety Gear
Cutting with a circular saw, road saw, or anything with a high speed blade will cause debris to go flying everywhere.
That means you need to wear gear the protects you, especially your face:
Safety Goggles
Helmet (With Face Shield)
Gloves
Long Clothing
Respiratory Equipment
Steel Toe Boots
Follow Manufacturer Directions
Just like a car needs specific gas, saws and blades have their own instructions that need to be followed.
Always check the manufacturers manual as well as the product packaging for the proper safety and handling of the product.
Don’t Force It
Whenever operating saws, it’s a bad idea to force the saw. Avoid pushing it too hard.
Even diamond blades have their limits and will crack, chip, and break
Cut Straight
Simply put, do not cut with the blade at such an angle that the sides of the saw does any of cutting.
The blades are only designed to cut at the edges of the saw and not the flat sides.
Cool Down
Saws get really hot, really fast.
There’s a lot of power, friction, and force that go into grinding away the likes of concrete, brick, and asphalt.
If your saw doesn’t use water for cool down, you should take a break time.
The harder the material you’re cutting, the more cool down time you’ll need.
Cut Only What’s Recommended
Like stated above, many blades are only designed to cut certain materials.
Don’t cut materials you’re not supposed to!
Reading the manufacturers manual and following the recommendations is a must.
These instructions are designed to prevent the diamond blade from wearing down or ripping through material.
Routine Maintenance Checks
Before operating any saw with a diamond blade, it’s a good idea to make sure nothing is already damaged.
Check both sides and the edges of the blade to ensure it’s ready to go.
Diamond Blade Dos & Don'ts
By Rebecca Kanable, contributing writer
Diamond blades get beat up in a variety of ways. They get burned, stuck (and then hit with a hammer), bent and broken. It's not pretty and it's not good practice.
Whether you're using a diamond blade on a gas-powered saw, electric hand saw or walk-behind saw, a few words of wisdom can help save blades from misuse and abuse.
Factors affecting longevity
Blade life can vary greatly depending on a number of variables. One key factor is blade quality (diamond quality and concentration, and segment bond and width). Consider that two blades of the same diameter could have different diamond depths, amounts of diamond in the blade segment and segment heights.
As with traditional diamonds, there are different grades assigned to synthetic diamonds for saw blades. "A higher-quality diamond is going to perform better and definitely last longer," says Ted Skaff of Pearl Abrasive Co. In some cases, it may also grind or cut faster, as well.
Another key factor in blade life is the material that needs to be cut. Cutting a hard material such as concrete requires a different blade than one used to cut a soft, abrasive material such as asphalt. The harder material requires diamonds to be exposed more quickly, and a softer bond to hold the diamonds to the segment.
"You could use a blade designed for concrete to cut asphalt and it will cut really fast, but it won't last very long," says Thom Fisher with Diamond Products.
How concrete cutting impacts blade life depends on the aggregate size, sand type (sharp and abrasive or round and non-abrasive), aggregate hardness (determined by rock type) and reinforcing steel (amount, grade and gauge). For example, a coarser aggregate with a lot of sand will wear a blade faster than concrete with less sand and less aggregate, Skaff says.
However, softer and more abrasive green concrete will require a harder bond with undercut protection, Fisher adds.
How long a blade will be useful on a job depends on the amount of cutting that needs to be done. Using a blade to cut a driveway is different than using a blade to cut a long stretch of highway, Fisher points out.
The saw used with the blade also affects blade life. A tool with high rpm will wear a blade faster than a tool with low rpm, Skaff says.
The operator can shorten the life of a blade, as well. An operator applying more pressure will tend to wear out a blade faster than someone applying less pressure, Skaff says.
Tips for longer life
Given these variables, manufacturers offer the following dos and don'ts to maximize blade life.
Do use the right blade for the job. There are blades designed specifically to cut concrete, masonry and green concrete.
While general-purpose blades can cover a variety of cutting tasks, application-specific blades are engineered with a specific bond to meet the needs of a certain application. They do the best job and will last longer, Skaff says.
To help find the right blade for the task, Hobie Smith of MK Diamond Products Inc. suggests answering the following questions:
What material are you cutting?
What type of cutting equipment will be used?
How much cutting will be done?
How fast do you need to complete the job?
Do use a wet blade only when wet. A common operating mistake is using a wet blade dry. "A wet blade should never be used dry," Skaff says.
Fisher agrees, noting, "We get blades back all the time that are fried because water wasn't used. It doesn't take very long for the friction of concrete (or even asphalt) to burn up a blade."
Even dry blades can be used wet; doing so might actually increase production and blade life. Heat and dust are enemies of a blade, Skaff explains. Using a blade wet eliminates both enemies.
Don't bury the blade. Another common mistake is burying the blade all the way to the flange, or forcing the blade through the material being cut.
Forcing the blade through material will damage the saw by increasing the amperage, burning up the motor and overheating the blade, which causes premature wear and damage, says Skaff. He has seen blades burned so badly they have a purple rainbow around the rim.
Metal in the diamond rim can get so hot that it actually covers the diamonds. Glazing over diamonds on the rim can cause blades to dull and stop cutting, even though there's a lot of life left on the diamond rim of the blade, Skaff continues. This issue can be solved in the field by dressing the blade.
"You always want to let the blade do the cutting, whether you're using a handsaw, stationary saw or walk-behind saw," he adds. "That will increase the life of the blade and the life of the tool."
Smith advises using a step-cutting technique.
This involves making several passes to complete the cut. "In reality, you shouldn't even use half of the diameter of a blade," says Fisher.
Don't be pushy. Any equipment can fail if it's pushed beyond its operating limits; saws and blades are no exception. Avoid pushing a blade too hard just to get a job done fast.
Do install the blade properly. Often, saw operators will spin a blade in the wrong direction. While a blade will still cut if it's spinning the wrong way, the diamonds will be eaten up quickly, Fisher points out.
Pay attention to the directional arrows labeled on the blade to ensure the blade is installed properly and spins in the intended direction.
When mounting a blade to walk-behind saws, don't forget the drive-behind pinhole, reminds Fisher. In addition to the center arbor, the second hole on the flange steadies the blade and prevents wobbling.
Do use caution in the turns. Skaff offers another word of caution for walk-behind saws: "If your blade is an inch deep into a cut and you want to turn, don't rotate the saw while the blade is still in the cut. I've seen segments of blade bend and break because a machine changes directions while the blade is still in the cut.
"If you're going to change directions," he continues, "make sure your machine is off, the blade is up out of the cut and the machine is unplugged."
Resources available
Manufacturers offer manuals that cover diamond blade basics (how to use water, how to mount blades, how fast to spin blades, how to determine the proper size saw for the proper blade, etc.). Contact your saw or blade manufacturer directly, or work with your local dealer, rental center or supply house to make sure you have access to all the information you need to operate efficiently — and, of course, safely.
Myth: Cutting with Water Makes Diamond Blades Last Longer
With the high level of science involved in developing and selecting a diamond blade, research has shown that water plays a role in how the blade cuts when using a handheld saw. It can be easy to assume that the life of the blade would increase because of the many positive factors that come from cutting wet, however, cutting wet does not necessarily mean a longer lasting blade. Water creates abrasive slurry which will add wear to normal segment life.
What are the benefits of wet cutting?
Provides a more efficient cut: As water flows onto your material, it limits resistance by clearing away loose aggregate and increasing the speed of the cut.
Compliant with OSHA crystalline silica rule: Water works as a dust suppressant to reduce exposure to airborne particles that can be harmful to your health. Inhaling crystalline silica dust puts you at risk for lung issues like silicosis and tuberculosis.
Protects the integrity of the blade: The chances of the blade overheating are reduced due to the water cooling down the blade. Overheating can lead to the blade warping, causing both the core and segments to crack.
To find the blade that meets your needs, reach out to our blade experts at (800) 233-8655.
