Description of LENOX 29966 66CG Carbide Grit Hole Saw
Carbide grit hole saw. Features a hard tungsten carbide grit cutting edge. It will cut tough abrasive materials such as fiberglass, ceramic tile, laminates. Carbide grit edge will not snag or chip when cutting thin materials. Measures 4-1/8 inches diameter.
It was advertised that tiles would work. I worked on a piece of 5/8 tile for about 45 minutes, using water to keep the blade cool and not burn it. I only had to cut two holes, and this blade couldn't even cut one hole. After about half an hour I was only half over the tiles and gave up. I don't know about other materials, but it's nonsense about tiles. I returned it and bought something else to do the job.
I used this to cut 4 inch round ceiling boxes in a 96 year old house. Ceilings in horsehair stucco and slats. Pipe wiring that runs directly through the plaster. I use this hole saw with a suitable mandrel in a large 1/2" variable speed cord bit. Running slowly, returning frequently to clean up and cool is great. I was able to cut through both plaster and batten. The hole was very clean and the hole saw is still in shape like new to cut a lot more.
Had to cut 4" vent holes in old cement board trim. Cutting was easy and after I was done the blade still looked new. MAY 2014: I used this saw again, only the second time, and the threads snapped and the Lenox mandrel just turned in the hole saw. I had to put the saw in a vise to remove the mandrel. I paid $60 for this saw which is now useless. JUNE 2014 Solution found. I bought a 5/8-18 tap and fixed the threads as best I could. I bought a Lenox Snap Back and now the saw works perfectly…