4" Dry Diamond Core Drill Bits for Brick, Block or Masonry, 9.5" Drilling Depth, 5/8"-11 Arbor

Task: Move my dryer vent lower, through a wall made of a row of concrete block faced with full brick, so about 11.5" - 12" thick.Skill level: fairly accomplished home handyman, comfortable with power tools. I had never done this before though.Solution: this bit with a [ https://www.amazon.com/gp/product/B00DHJK9JS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 ] adapter and a 9 amp Chicago Electric 1/2" D handle drill. This is a rotary drill, NOT a hammer drill.I started by drilling a 1/4" hole all the way through from the inside so I knew exactly where to drill from the outside. This also allowed me to place the hole in the center of the void of the concrete block, which makes drilling faster and easier.I DID have to make a template out of a piece of 2 x 6 lumber with a 4.125" hole to hold the 4" bit in place to start it. I already had a 4.125" hole saw. You may need to buy one, or perhaps an adapter with a pilot bit. I temporarily attached the wood template to the brick with a couple tapcons.I started drilling very carefully, using a torpedo level on the bit occasionally to stay fairly level. I also poured a little water on it occasionally - I don't know if that mattered or not.MY learning curve - I knew if the bit bound up I could be injured - these bigger drills are no toy. So I was attempting to be super careful. Regardless experience is the best teacher. I had only used this particular drill once before (all day though, to mix many bags of mortar in a bucket. I drove it so hard it smoked bad and it still works great).The drill is varible speed so, paying close attention, when I felt it start to bind I'd slow or stop, feeling my way. But! at one point I had accidentally engaged the trigger lock. So it stars to bind, I back off the trigger, it still runs full speed. 'Bapping' my hands a few times until it fell out of the hole and on the ground, still writhing around like a wounded snake, until I could pull the plug.It could have been way worse. I have a smallish bruise on one forearm and a large bruise on the outside of one hand, with a little soreness in the wrist holding the d handle. I consider myself lucky. Be careful!No damage to the house, the drill, or the bit. It broke the wood template in two. It twisted and bent the adapter pretty badly (!) but I managed to straighten it out enough to finish with no further issues.With an eye on that dam trigger lock, I proceeded through the brick (that was the slowest going) and into the first side of the concrete block. Then I pulled the drill out and knocked the brick off, which gave me more depth / room for the bit, which is how I drilled deeper than the 9" length of the bit. I hope I explained that clearly.Then completed the hole.Result: this bit worked perfectly. It appears to have more life left in it too. It took about 30 minutes including binding. It takes some muscle but not too bad.Verdict - many thumbs up!

I bought this drill to route a 1" exhaust out of my garage. This drill was the 1 1/4" model that doesnt have a pilot bit in the center. I already had a short 1 1/4" core drill that I used for a tile job years ago, so I used that to start the hole in the brick. As soon as I got about an inch into the brick, I switched to this core drill. It doesn't drill super fast, but it makes steady progress and leaves a really smooth hole. I've drilled two holes with this core drill so far and it has held up really good. Another plus is that it doesn't blow out the exit hole. The exit was clean as the entrance.

I use to core holes in curbs for drainage systems. The work great but only last about 10 holes before they wear out

Does exactly what it needed to. Drilled a 1 1/4" hole though my basement wall to the exterior of my house.1. It's tough on your drill so keep that in mind. I bought a $50 9amp drill from Harbor Freight for the job and it worked great and it was cheap enough that I didn't care about any damage to the drill. If you go about medium-speed it'll be ok.2. You don't need a pilot hole if you're careful. The bit will skate around on a flat wall. At first I thought 'I should have bought the pilot hole bit' but instead I used a demo hammer to start a bit of an indention in the brick which gave it enough purchase to start super slow and get it going.3. Take lots of breaks to let your drill and bit cool down.4. 9.5" is JUST long enough to get through the exterior masonry wall on my 100+ year old house. Your mileage may vary. Had to drill all the way up to the drill's chuck, but it made it.5. It says not to use a hammer drill and I didn't but I did wiggle/rotate the bit a little as I was drilling and it seemed to expel more brick dust so...6. You do need to push so if you're drilling above your center of gravity you may need to be braced to get proper leverage.7. Wasn't too messy. I had a shop vac running by the hole and when I was done I didn't even have brick dust on my shirt.Basically, it's a good and inexpensive solution if you need to cut a couple holes in your house for wire or whatever. Can't speak to durability but it seems fine after cutting through 9.5" of brick.In conclusion, it's pretty cool to cut a hole in your house and this is a good way to do it.

As an electrician, making a hole in brick can be difficult and sloppy. Using this core bit made the job look professional and it was clean looking. In order start the hole, since it has no centering bit, I drew an outline of the pipe in marker, and I then drilled some pilot holes and chiseled out the center. I was then able to finally get the hole started in the brick. It didn't need much pressure to cut. The wall was 12" thick, but the 5/8" arbor and the drill chuck was able to make up the difference.