Ratings & Reviews for Kobalt Diamond Core Drill Bit 2-1/2-in Dry Diamond Core Drill Bit for Stone

Awesome at drilling throug ceramic tile already up

Great product! Drilled hole in tile as described.

Worked great

I think the negative reviews are from people who didn’t know what they were doing because this worked perfectly on porcelain tile. Start at high speed at 45 degree angle and gradually move to straight on. Spray consistently with water while drilling and clean out the hollow bit too. Drilled 8 holes and could have continued drilling with no problem

Return process was easy

Never actually used the product, I found my old one

Buy extra bits when drilling tile!

As I mentioned in my review of the larger size bit this design was able to accomplish (with a lot of time) what my carbide bit failed at (again not sure if I used it incorrectly or it was the wrong tool for the job). Partly I was very cautious as I didn't have the time to risk ruining my only other bit and have to run to the store and get more bits (and honestly they should be able to make more than 1 or 2 holes before wearing out). But ultimately this bit got the job done with enough patience...

Go slow and use water

I was glad that I bought this bit along with the carbide ones because the carbide ones started out great but in the end I had to use the diamond bit to finish the holes. I did go slow and use some water both to cool the bit and clear out the hole as I went. These seemed to take longer to drill but ultimately got the job done.

Great product

High quality and a great product, I would recommend this product

Excellent quality

I used another brand of this same drill bit and this drill bit was far superior as it did not become dull after drilling the same amount of holes through tile.

Not for Procelain

Purchased the 5/16 bit on 12/3/22. After 3 holes it was no good. Thought maybe that one was just defective so I purchased another; same result. Purchased 3 in total and only got 9 holes done. Where is the quality control. Don't sell it for Procelain if it only cuts glass and ceramic. I'm so disappointed! $5 plus per hole...ridiculous!

Great deal for small jobs

Worked pretty well. Seemed like it was gradually wearing down after about 6 cuts, but that's all the use I needed to get out of it, and it was 1/3 the price of some of the other brands.

Will Easily Cut Through A Ceramic Sink

I needed it to open up the slot in the top of my old bathroom sink for the new faucet drain handle. My regular metal files wouldn't touch the ceramic basin but this thing easily cut through 1/2" of solid ceramic with ease. I used a small amount of water to keep it cool and help clear the dust and it worked as advertised.

mnichols

Only cut 2 holes and it was shot. I definitely wouldn’t recommend this product. I’ve tried HD and Habor Freight bits and honestly they must all be made by the same company. Not recommended.

Mnichols

Made cutting the tile very easy. Long lasting diamond saw really helped.

A little hard to get started.

i had a little difficulty getting the bit started but once I did it worked fine.

Difficult to use

this is a very hard bit for DIY'rs to use. there is no center drill which allows the drill to just skate across the tile. A small center drill would be most helpful to guide. I realized that in order to use you must use angle the bit and gradually turn it up straight. Most will find this difficult to use.