Concrete block is abrasive, and abrasive material wears a diamond blade's bond away faster than it wears the diamonds. The MK-50 answers that with a hard matrix: the bond erodes more slowly, so it holds each diamond in place longer and turns abrasion into cuts instead of into lost segment height. MK builds the 50 series specifically for block, both precision and slump, and grades this one Supreme. This is the 18-inch blade on a 1-inch arbor.
Built for
- Block layers and masonry contractors cutting precision and slump block to length
- Precast and block yards where cost per cut is the number that matters
- Hardscape crews cutting retaining-wall block and cap units
- Masonry saw operators running high volumes in abrasive material all day
Specifications
- MK Diamond part number 128751
- Series: MK-50
- Diameter: 18 inches (457 mm)
- Segment width (kerf): .142 inch
- Arbor: 1 inch
- Grade: Supreme
- Rim: segmented
- Cutting method: wet
- Bond: hard matrix
- Material: concrete block, precision and slump
Matching the bond to the material
Diamond blade selection starts with bond hardness, not diameter. The metal matrix holding the diamonds has to erode at roughly the same rate the material dulls them. Erode too slowly and the blade glazes over and stops cutting; erode too fast and you throw away segment height you paid for. The working rule is that harder, denser material wants a softer bond, and softer or more abrasive material wants a harder bond. MK Diamond builds the masonry line around exactly that split: the MK-10 is a soft matrix for hard brick, the MK-50 is a hard matrix for abrasive concrete block, and the MK-30 sits between them as a medium-hard combination bond for crews that cut both.
Where this blade sits in the MK masonry line
MK Diamond groups its wet-cutting masonry blades by bond rather than by saw. The MK-10 is the soft-matrix blade for brick, including hard and dense brick. The MK-50 is the hard-matrix blade for concrete block, both precision and slump. The MK-30 is the medium-hard combination bond that cuts either one, trading some speed and some blade life for not having to change blades between materials. If your work is almost all one material, the dedicated blade is the cheaper blade per cut; if you move between brick and block on the same saw all day, the combination blade usually wins.
Operating notes
Run this blade wet. Water does two jobs on a segmented masonry blade: it clears the slurry out of the kerf so the segments keep biting, and it carries heat away from the steel core, which is what keeps a core from warping or losing tension. Feed at a steady, moderate rate and let the blade do the work. Forcing a segmented blade into dense material heats the core and rounds the leading edge of the segments rather than cutting faster. Never exceed the maximum operating speed marked on the blade, and check that the saw arbor, flanges and blade guard are in good condition before mounting.
Frequently asked questions
Why does abrasive block need a harder bond?
Because in abrasive material the bond wears faster than the diamonds do. A soft bond releases diamonds that still have cutting life left in them, which shows up as short blade life. A hard matrix erodes more slowly and keeps each diamond working until it is actually worn, which is where the extra cuts come from.
Will the MK-50 cut brick?
It will, but slowly. Brick is harder and less abrasive than block, so it does not erode the hard matrix fast enough to keep fresh diamond exposed, and the blade tends to glaze. For brick MK publishes the soft-matrix MK-10, and for crews cutting both materials the medium-hard MK-30 combination blade.
Is this a wet blade?
Yes. Run it wet. Water clears the slurry from the kerf and pulls heat out of the steel core, which is what protects the core from warping in sustained production cutting.
What arbor does it take?
This part number is a 1 inch arbor, the standard for masonry table saws in this size class.
What if the blade stops cutting?
A hard-bond blade that slows down in the same material has usually glazed over. Making a few cuts in a softer, more abrasive material will dress the segments and expose fresh diamond. If it glazes repeatedly, the bond is too hard for what you are cutting and a softer-matrix blade is the right fix.
Discount Cleaning Products is an authorized MK Diamond dealer with US-based support. Our staff works with masonry, restoration and building-maintenance contractors every day, so if you are unsure which block blade is right for the material you are cutting, call or email us with the saw and the material and we will point you at the correct part number.
