At 18 inches this is a deep-cut pavement blade, the size a crew puts on when the trench has to go down far enough for a utility line rather than just through the surface course. It is MK Diamond's Premium Grade wet asphalt blade, rated Better on asphalt in MK's own chart, and it carries a slightly heavier .142-inch kerf than the smaller sizes in the family - the extra core thickness that a larger, deeper-loaded blade needs to stay true in the cut.
Built for
- Full-depth utility and trench cuts in asphalt pavement for water, sewer, gas and fiber crews.
- Street openings, patch boxes and saw-cut layout ahead of a mill-and-patch repair.
- Squaring off failed pavement on parking lots, drives and paving jobs before removal.
- Municipal and DOT street department work on walk-behind and cart-mounted wet saws.
- Rental fleets that need a known asphalt blade for the 8 to 20-horsepower saws they already rent out.
Use Cases
The single most expensive mistake in pavement sawing is running the wrong blade in the wrong material. MK Diamond says so directly in its own blade manual: the most frequent problem it sees is a user cutting the wrong material with the wrong blade. Asphalt is abrasive and it loads a cut differently than cured concrete does, which is why MK builds a separate asphalt line and rates the MK-705W as Better on asphalt in its published application chart.
One caution worth reading before you order: MK does not recommend the MK-705W for asphalt over concrete. That job is a different blade in MK's lineup (the 600 series combination blades). If your cut will punch through the mat and into a concrete base, ask us and we will point you at the right part instead.
Getting full life out of it
This is a wet-cutting blade. MK is unambiguous that wet cutting blades can never be run dry, and publishes a water rate of 2 to 4 gallons per minute delivered evenly to both sides of the blade. Water does three jobs at once: it cools the steel core, it keeps the dust signature down, and it flushes the fines out of the kerf. Contractors describe the same thing in their own words - water helps the fines wash out of the cut and makes the blade last.
The two failure modes crews complain about most are both avoidable. A blade that stops cutting has usually glazed over from being forced; MK's guidance is to let the blade cut rather than push it, so fresh diamond keeps exposing. A blade that dies with segment still on it has usually been undercut, where slurry grinds away the core beneath the segments. More water, shallower step-down passes and staying out of the sub-base are the standard fixes.
Specifications
- Model: MK Diamond MK-705W, Premium Grade for asphalt
- Manufacturer part number: 133850
- Diameter: 18-inch (457mm)
- Width (kerf): .142-inch
- Arbor: 1-inch
- Segment height: 12mm
- Horsepower range: 8 to 20 hp
- Construction: laser welded
- Cutting method: wet only
- Material rated by MK: asphalt (better). Asphalt over concrete is not recommended.
- Available in this family: 12-inch through 30-inch
Frequently asked questions
Why is the kerf wider on the 18-inch than on the 12-inch and 14-inch?
Larger blades carry more load and more overhang, so MK specifies a thicker core and kerf as diameter climbs. This size is .142-inch where the 12-inch and 14-inch in the same family are .125-inch. It is a manufacturer-set pairing, not an option.
What horsepower does an 18-inch blade need?
MK publishes an 8 to 20 horsepower range for the whole MK-705W family. Toward the top of the diameter range you want to be toward the top of that band, or the saw will lug and glaze the blade.
Can it be run dry?
No. MK states that its wet cutting blades can never be used dry. Feed 2 to 4 gallons of water per minute evenly to both sides.
Is this rated for asphalt over concrete?
No. MK marks the MK-705W not recommended for asphalt over concrete and routes that job to its combination blade series. Ask us before ordering if your cut will reach a concrete base.
How do I avoid losing the blade to undercutting?
Undercutting is slurry grinding away the steel core below the segments, and it is what kills a blade that still has segment left. Keep the water volume up, take step-down passes rather than one deep plunge, and stay out of the sub-base material under the pavement.
Discount Cleaning Products is an authorized MK Diamond dealer. Blades ship direct from stocking inventory, orders are handled by a US-based team that works with contractor and municipal purchasing every day, and we can help confirm arbor, kerf and horsepower against your saw before you order.
