Customer Reviews for VEVOR Core Drill Bit, 50.8 mm Diameter 11 Threaded, 241.3mm Depth Diamond Dry Coring Bore Tool with a Pilot Bit & Blade, Masonry Hole Saw Bits for Hard Concrete Brick

This core bit worked perfectly to core a hole for a recent mini-split HVAC install through a CMU wall. It chewed right through the block with ease. I used a standard 1/2' Milwaukee drill and a spray bottle in my application and the bit survived to drill another day. I think you could get a lot of use out it before replacing as long as you keep the bit wet. Bottom line is it is a good value and good quality. The included grinding disk is a plus and also good quality.

Worked good cut 6 holes threw 8 in concrete still seamed to cut the last hole good . I would buy again if needed to very reliable drill bit

Drilled through 8\" cinder block to shorten dryer exhaust pipe. Dryer works much better and should result in lower energy usage.

This worked really well drilling through the side of a concrete storm sewer. BUT! I had to buy a $240 hammer drill. This will not work in standard 3 tooth chuck of the hammer drill I already had.

I have not yet used this bit, but after reading some of the reviews, I felt a comment was in order. People are complaining about the pilot bit, but if it is used correctly, it is a huge help. Note the use of the term "pilot bit". That means you need a pilot hole. The proper way to use it is to remove the pilot bit from the mandrel and insert it by itself, into a hammer drill and use that to drill your pilot hole. Then you install it back into the mandrel and screw that into the coring bit. The coring bit should be used only with rotary motion, not hammering, unless you're fine with huge breakout on the back of your hole. I will write a follow up review or update this one after I actually use it, but I wanted to point out the error in some of the reviews I've read.

Overall a pretty good drill bit. I needed to drill five - 2 inch holes through a 5 inch thick reinforced concrete floor. After starting the pilot hole, it was tough to get the large bit started due to the size. I found starting more at a slight angle, then gradually moving to a straight up angle made it easier. It is not an easy hole to drill, but this drill bit works well. The only negative is the set screws for these pilot drill bits will vibrate loose causing the main bit to really wobble badly. I had to retightened the bit often. And.. Definitely use water. Much faster, cleaner, and no dust. Well worth the money compared to hiring others or renting equipment.

Was really skeptical of this due to price. I was able to core 2 holes full depth 14 inches in a poured solid concrete and block wall. Went slow with variable speed wet angle grinder with lots of water. Bit looks fine and ready for some more.

While pouring a new garage floor, I decided to stub in for a future washer and dryer rather than keeping it in the basement. Bought the 2 1/2" core drill to safely run 2'' pipe through an 8' basement wall. I had my doubts, but thought I'd by this set. I used a 1/2 inch Skill, hammer drill and it was a chore, but very doable. Saved me a $100 from the local tool rental.The center drill is pretty much worthless, too much flop to get a good starting cut. I drilled a 2 1/2'' hole in a scrap masonite and used it as a guide to get each hole started.Pro's..... It will get the job done.Cons...... You can skip the gym that day.... It's a workout. LOL

Drilled 3 holes in standard patio. Worked as expected. The drill bit was useless. Made a would jig to align boring tool instead of using the drill bit.

Worked great, only drilled one hole so far but it worked great