Is this used for floor core drilling? It says hammer drill which I though was for walls. If drilling for a 3/4 conduit what size core would you use? 1" ? Also. how many uses do you usually get from a core bit before you have to replace it when using it. i know it probably depends on slab thickness...but approx. THanks.
People sometimes interchange the term "boring" with "coring". We're "making a hole". Moving past semantics, the next consideration is the type of material you are boring through. Since floors, ceilings and walls can be made out of the same material, you can use the same bits for floors or walls.
The thickness of the material to be bored through affects the strategy. If the material is thicker than the length of your coring bit, you must cut until you run out of stroke, break out the slug, then resume coring.
The difference between floors and ceilings affects the strategy. Coring the floor, you can use the vacuum base of the core rig. For wall coring, you may first have to bore a smaller anchor hole with the bit you pictured to anchor the larger coring rig in a horizontal configuration. A ladder or scaffold may be required. It is easier to keep coring bits lubricated while boring floors because of gravity.
The diameter of the hole affects strategy. Larger diameter bores can be more efficiently executed with coring bits. For example, consider a smaller scale. If I need a 1.375" KO in a panel enclosure, I prefer to use a hole-saw (similar to a coring bit in design) over a large "step drill" bit. Less material needs to be actually cut by the hole-saw and it is therefore more efficient, IMO.