Homeowner/DIY tips: We are installing a 8" exhaust vent through our exterior brick house. Here are so things we learned along the way.1. The 8" core bit is heavy and you need something like a joist/stud drill that has enough torque/power to make this work.2. A heavy duty hammer drill/SDS demolition/rotary hammer will make drilling easier but these fancy drills are not required.3. periodically wet the core bit in a bucket of water to preserve the diamond coated cutting bits. It will be a pain in the butt but it will make cutting easier. You don't want to ruin your bit because a damaged bit will not cut or will take forever to cut.
GREAT BANG FOR THE PRICE. GREAT QUALITY. EASY TO HOOK UP. EASY TO USE. I INSTALL EXTERIOR METAL RAILINGS. INSTALL 2" PIPE TO CONCRETE. CORE HOLE FOR INSTALLATION OF PIPE.
Performed well through 8" of solid concrete. Tracked solid, even with a hand drill. Would buy again and the price was great which also included the bit and cutting wheel.
The product worked great other than the Allen screw that holds in the drill bit. It doesn't hold it in tight and if you try to tighten it, it will break.
I'm giving it 5 stars because it did exactly what I bought it for. The price was great! The pilot bit was the weak point as it didn't really keep the core drill centered to start the hole. It wobbled all over due to its length. I was able to chisel a starting ring and from there the core drill did its job. It even cut through the rebar that I unluckily encountered. You have to be patient and take frequent breaks to allow the core drill bit to cool. This is required with all dry core drilling.
This is an awsome core drill, i was skeptical at first, because of some bad reviews i saw. But this thing went thru a foot of rock wall with no issues. Bit is still intact,all teeth are good. Would definitely recommend it.
I bought this bit to bore a 4 -1/2" hole in my 5in thick, steel reinforced concrete in my upper patio to drain the Dry Below system. I used a 12 A hammer drill in drill mode. I used a little water and the bit walked through the concrete and steel in about 10min using no pressure just the drill motors weight. This bit performed perfectly. Thanks for asking.
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