It leaves a cylinder shape which often is used as sink holes or to feed lines and pipes.
Marble hole drill bit.
Rather than relying on channel action like normal bits core bits have a central pilot bit that holds the bit in place while the outer sections of the bit cuts a hole through stone.
Hole bits or core bits are specially designed drill bits that are tipped with either diamond or carbide.
Yotino 15pcs diamond drill bit set 0 24inch 6mm small diamond hole saw set hollow core drill bit set for glass ceramics porcelain ceramic tile marble 3 9 out of 5 stars 116 9 99 9.
These core bits are made up of a concentration of diamonds and metal bonds in order to cut the hard surface of the granite.
Marble drilling bit self centering marble drilling bit creates the perfect indentation to keep marbles in place on a board.