Part number 155947 is the 5-inch MK Standard dry masonry core bit from MK Diamond. It drills clean round holes through soft brick and concrete block without a water feed, which is what makes it practical inside finished buildings and on service calls where setting up a wet coring rig is not worth the trouble. Five inches is a common diameter for larger vent, conduit and service penetrations.
Specifications
- MK Diamond part number: 155947
- Series: MK Standard dry masonry bit
- Diameter: 5-inch (127mm)
- Overall length: 10 inches
- Drilling depth: 9-1/4 inches
- Segment height: 7.5mm
- Connection: standard 5/8-inch to 11 threaded nut
- Minimum drill rating: 10 amps
- Maximum / minimum RPM: 5000 / 700
- Cutting method: dry
Construction and use
MK Diamond publishes the MK Standard dry bits as laser welded, which is the joint that survives the heat of dry drilling, and lists them for soft brick and concrete block. They thread onto most hand-held drills through the 5/8-inch to 11 connection. Run the bit within the published RPM band and let the bit do the work; pushing a dry bit harder to speed it up mostly generates heat, which is the fastest way to lose segments.
Fits
Specified by diameter and thread rather than by drill model. Confirm your drill takes a 5/8-inch to 11 threaded bit, is rated at 10 amps or better, and runs within 700 to 5000 RPM. MK notes that additional diameters and lengths are available on request.
Buying from Discount Cleaning Products
Discount Cleaning Products supplies masonry drilling and surface preparation consumables to contractors and facility maintenance teams across the United States. We stock genuine manufacturer parts, so this bit ships under the MK Diamond number listed above. The MK Standard dry line is published from 1-inch through 6-inch, so contact us if 5-inch is not the diameter you need.