For cutting holes in plaster for electrical boxes. The plaster is about 1 inch thick. The first few holes were ok but the fifth hole barely made it. The sixth hole only went about 1/4 inch. Dumb and shot. I only have a few holes left and there is nothing left to do but order another one.
This diamond coated hole saw is the only one you can use to drill holes in hardboard or Du Roque, like 25 holes in a newly installed soffit floor. We used a Hardee board and started with a regular round vent hole saw. We just made one hole with a regular bi-metal hole saw and the teeth were gone. Diamond completed 25 holes with no problems. still like new. Wow!
Not sure what the walls and ceiling of my 1930's are constructed of, but it's plaster about 1/2 inch thick drywall over what to be seems like some kind of 1/2" cement board. I shudder at how much my house weighs. In any case, a regular hole saw is good for no more than two holes before the teeth are completely gone. This thing will do though Out A regular hole saw is probably better for wood, but will do for cement board or something similar.