Armeg3/8" PTC Carbide Porcelain Drill Bit - 1 Count

I was trying to drill mounting holes in very hard bathroom tiles using my masonry bit. It was not working. I went on line looking for helpful videos and ran across one that recommended the Armeg bit for this situation.The Armeg made a huge difference. I put two layers of masking tap over the planned location of each hole. I used a center punch to put a dimple n the tape where I wanted to start the hole. The Armeg bit was able to start the hole without 'wandering'. Drilling through a tile still took a few minutes, but finished the job that I hadn't been able to without this bit.

When I was researching porcelain tile, I found the higher the hardness rating the better. I went with a 5 rating, but I never considered having to drill into it. I knew nothing about drilling into porcelain tile. After trying a masonary bit without so much as a scratch on the tile, I figured I was dealing with some kryptonite space rock. I started out with a 5/16th hitachi diamond tiped bit, but still couldn't get the 1/4 inch wall anchors to go thru and decided to try the masonary bit again to ream out the hole. Completely ruined the bit and not a scratch on the tile. Found these PTC porcelain drill bits and ordered the 3/8th size to the ream out the hole and it worked great. I can't speak to how they work from the start, but did a great job reaming out these holes. I used a cordless drill and a emptied out spray bottle with water to keep the bit cool. The only thing I would change with the design would be to be to put some groves and maybe create a hexigon shape on the bit shaft as it tended to slip in the chuck under preasure using the water for cooling. Probably wouldn't be an issue in a corded drill where you could use a chuck key to tighten.

Expensive but was one of the few bits that would handle the porcelain tile.

Dont run the bits at a crazy RPM and keep them wet. Impressed with the life of these, considering the price they should.

Installed a glass shower enclosure and needed to drill 8 5/16 holes through porcelain tile. Initially used a carbide tile bit from your local home improvement center which barely broke the surface of the tile and then just spun for 10 minutes even though I put my full 200 lbs weight behind it. Bought the Armeg bit and all holes were complete within five minutes. Granted, I had to apply a bit of pressure but certainly not the pressure I applied with the Home Improvement bit. Yes, they're expensive but worth every penny.