1-1/8" Wet Diamond Core Drill Bits for Concrete with Rebar, Brick, Block, Masonry, 15" Drilling Depth, 1-1/4-7" Thread, Laser-Welded Segments for Construction & DIY Home Renovation

I wanted to make water fountains out of two pieces of sandstone. I needed to drill 1” holes 26” through the length of the stone. I bought two bits from two different manufacturers incase one did not work as well as another. For once, Blue works better than Red and as it turned out the HBKEEN performed the best. I used the other brand for only a short period of time due to the obvious performance differences. The HBKEEN cut faster and was easier to clean out. The sandstone packs inside the core bit and I found it easier to wash the waste out with a hand pump sprayer than to try to knock the waste out. The HBKEEN has teeth with an inside diameter smaller than inside diameter of the tube, so the core is easier to clean out. The other brand has an inside diameter which is close to the same, which makes clean out harder. Even with the HBKEEN, it needed to be cleaned out ever inch or so.The only drawback to the HBKEEN was that the threads for the adapter are recessed about 1/2 inch or so and my adapter would not engage the threads. Using a hacksaw, I cut about 1/2” off the end of the bit. I ground the end so that the shoulder would be square with the adapter. Then it worked fine. I bought extensions so I could drill the full 26” from one end for a straight hole.

Was able to drill through 17 inches thick and it got the job done. It was worn out when I got through but it did work well. It even cut through one rod of ½ inch rebar.

overall quality of the core bit is good, but I wish they just made the base larger somehow to accept a larger thread size that's common for chucks with a water feed system.note: this WILL NOT, accept all 5/8-11 adapters. the threads start about 3/4in from the end, so many adapters may not engage the threads enough or at all. I cut most of the unthreaded part off the end of the bit on a bandsaw and its fine now, but most people may not have this option.

Drilled a 10" deep hole in granite with a grinder at 2500 rpm. Tip is still very newish. Clogged a couple times but to be expected not using a boring rig.

I went to a tool rental and it would've cost $75 to rent a drill and then you had to buy the core drill bit @ $150. So I checked on this with a 1/2" x 1-1/4"-7 adaptor and it was a lil tough to push but it was also a 14" thick solid concrete wall with rebar. Was tough on me and the drill but not the bit it worked great. Still looks new. Just remember to use a spray bottle to keep spraying water on it.

I wasn't sure if this core drill bit would help me do a core sample in a 14 inch concrete wall. To my surprise it easily did the horizontal 14 inch core. I used a garden hose to drip water from above during the drilling. I used my Bosch Hammer Drill attached to the core bit. That drill has a few years but it's a beast. I highly recommend this core bit.

Not a bad deal for this bit, was able to complete about 12 holes with concrete then cue deck pan before noticing three of the teeth were chipped off. Not bad for the price point, had to order three bits to complete a total of 38 holes.

The first time it was used two of the teeth broke off. Couldn't even finish what was started. I had to rent a tool for the job.