Cutting a fresh slab is a race against the clock. Contraction joints have to go in during the sawing window, after the concrete is hard enough that the blade does not tear aggregate out of the surface but before shrinkage stresses crack the slab where they please. Miss that window and you are either chasing ravelled joint edges or explaining a random crack to the owner. The MK Diamond MK-605W in 18-inch diameter with a .142 kerf is the largest premium-grade green-concrete blade MK builds, for the slabs where a smaller blade cannot reach.
Built for
- Cut contraction and control joints in freshly placed slabs during the sawing window
- Saw deep joints in thick commercial, industrial and paving slabs
- Handle green-concrete joint work on walk-behind saws in the 8 to 20 hp range
- Run wet to hold heat down and flush slurry out of the cut
At .142 the kerf stays in the efficient range for standard contraction joints - it removes little material and lets the saw move quickly down the line - while carrying enough body to stay stable at 18-inch diameter.
At 18 inches this is the largest diameter MK builds in the MK-605W range, and it is the one to specify when green-concrete joints have to go deeper than a 14-inch blade can reach.
Green concrete blades use a softer bond than a cured-concrete blade. Fresh concrete is abrasive and it does not have the strength to keep the diamonds exposed on a hard-bonded blade, so a cured-concrete blade glazes over and stops cutting. The softer bond wears back at a rate that keeps fresh diamond at the surface, which is why using the right blade for the pour state matters more here than almost anywhere else in sawing.
All MK-605W blades are laser welded, which is the joint you want when a blade is run wet on a walk-behind saw. MK rates the range for saws in the 8 to 20 hp class and builds it with a 10mm segment height, so there is real diamond depth to work through before the blade is spent.
Specifications
- Manufacturer: MK Diamond
- Model: MK-605W
- Part number: 150169
- Grade: Premium
- Material: Green (fresh) concrete
- Diameter: 18 inches (457mm)
- Width (kerf): .142 inches
- Arbor: 1 inch
- Segment height: 10mm
- Horsepower range: 8 - 20 hp
- Bond: Laser welded
- Cutting method: Wet only
Frequently asked questions
When can I start cutting with this blade?
As soon as the slab is firm enough that the blade is not pulling aggregate out of the surface. Crews typically start green-concrete sawing a few hours after placement and use a scratch test on the surface to judge readiness. Cutting too early causes ravelling along the joint edge; cutting too late lets the slab crack on its own.
Can I use this blade dry?
No. The MK-605W is a wet-cutting blade. Water cools the core and the bond and flushes the slurry out of the cut, and running it dry will overheat the blade and shorten its life sharply.
Will it fit my saw?
It has a 1-inch arbor, which is the standard arbor on walk-behind concrete saws. MK rates the MK-605W range for saws of 8 to 20 hp. Check that your saw accepts an 18-inch blade before ordering, since the guard sets the maximum diameter.
How deep should I cut the joint?
The usual industry guideline is one quarter of the slab thickness, and deeper on slabs with heavy loading. At 18 inches this is the deepest-cutting blade in the MK-605W range, so it is the one to choose when a 12-inch or 14-inch blade cannot reach the depth the slab calls for.
Discount Cleaning Products is an authorized MK Diamond dealer. Our US-based team can help you match blade diameter, kerf width and bond to the saw and the material you are actually cutting, so you are not guessing at a part number. If you are not sure which blade in the range fits your saw, contact us with your saw model and horsepower and we will point you to the right one.
