Review on 🔪 Cutting Edge: CO Z Shank Cutter for Concrete Cement – Enhanced Performance and Efficiency by Ryan Person

I bought these after reading several reviews and because of the great price. I needed this for work drilling some access holes in a 4" thick log wall. I used the larger 2 1/4" drill bit to start my project. It was enough for a hole in the block, and then there were almost no "carbide" teeth left. I tried using it for the second hole but it didn't cut at all. Another issue was that the set screw kept loosening (despite being at maximum). After the drill came out a third time while drilling the first hole, I applied blue thread sealant and let it sit for a couple of hours before attempting to finish drilling the first hole. Since a larger drill bit is useless, I tried removing it from the hole. the shank, but the shank is round, there is no flat place to put the wrench to unscrew the bit. I had to clamp and hold it in a vise, which of course left scars on the stock. I threw the whole set in the trash and used my smaller Bosch SDS Plus 3/4" bit to finish the job. A bunch of little holes instead of one big hole.