Hole Saws & Core Bits
$95.50 to $1,007.50Shipping: StandardThe MK-Black is a supreme quality concrete coring bit with high diamond concentration and segment design providing superior performance in concrete with heavy steel reinforcement.
$67.85 to $921.70Shipping: StandardThe MK-Yellow is MK's standard core bit, and is an excellent choice for all types of general wet drilling. The MK-Yellow delivers fast drilling and good footage.
$83.80 to $720.20Shipping: StandardThe MK Diamond MK-Orange Wet Core Bit is a premium grade bit designed for wet drilling applications that would include light to moderate steel reinforcement.
Diamond hole saws and core bits can either be operated on a drill with a 3/8" or 1/2" chuck, or a variable speed grinder. Drills will typically be a single speed, ranging from 500-1,200RPM. Running a diamond hole saw or core bit on a drill will cut material slower than a variable speed grinder, but are safe for operating most sizes up to 4" (maximum safe speed for 4" bits is 1,000 RPM).
Variable speed grinders allow for faster cutting of material. However, when running a diamond hole saw or core bit on a variable speed grinder or polisher, the RPM you use will depend on the size of the bit. Optimal RPM speed for faster cutting for bits that are 1" or smaller is 4,000 RPM. Optimal RPM speed for bits 1-1/8" - 3" is 1,300-2,000 RPM. Standard 4" and 5" variable speed grinders start at 3,000 RPM, so if you have larger bits that require lower speeds, you may use a 7" to 9" variable speed grinder with a starting RPM of 600-900.