Choosing the right core drill bit size matters. First, match it to the wanted diameter of the hole. Later, check if the drill has enough power to work with big bits.
When you drill thick materials, you require longer core bits for smooth and precise cuts
How to Pick the Right Core Drill Bit Size
Diameters of core bits range to fit various uses. Small sizes between 1/4 inches and 2 inches work for precise tasks, like installing anchor bolts, tubes or conduits. Even smaller bits exist under 1 inch.
In the big end, diamond core bits for concrete reach more than 2 metres in diameter.
Wet and dry diamond-tipped core bits come in diameters from 1 to 14 inches, with depths of 14, 24, 28 and 36 inches. There are also special big bits for concrete in 14, 16, 18 and 20 inch diameters. The 20-inch wet concrete core bit has a lengh of 17 inches.
Diamond core bits for concrete come with open or closed head, diameters from 2 to 6.25 inches.
Amount of horsepower grows with the diameter of the hole. Main question when buying a new motor or rig: what diameters do you need? Match the motor to the bit and choose the right one according to its size.
SDS plus go up to around 4 inches for thin-wall core bits. A 3-inch core bit for SDS plus works well on blocks and concrete. Use a 3-inch diamond core bit with SDS plus rotary hammer if it is possible, but in drill mode only.
Hammer action can simply break the bit out of the concrete. Some bits come apart with different adapters for the hub, so they work for SDS, SDS MAX or average chuck drills.
For deep holes, use pilot bits or drill with cooling liquid. Makers make core bits in almost any size, so it is possible to get a 16-inch diameter with 28-inch length. Up to 12 inches diameter allows 16 inches depth, while 14-inch and bigger have variants.
Bits above 26 inches diameter are built with a spoke behind the hub. That hub helps distribute water to the walls for better cutting. While starting a hole, screw a button in the centre, so that the bit does not slip.
A 50 mm hole works well for pipework, because it gives space for movement and fits both waste sizes.
