ZELCAN Hole Saw Kit, 9pc Drill Hole Cutter Set with 30 40 65 80 100 mm Hole Drill Bits for SDS Plus and Max Hammer Drills, Circle Drill Bits Hole Saw Set for Concrete Brick Cement Stone Wall Drilling

Lo utilizo para instalación de mini split

I used them to cut through 9" of 5000 lbs cement. It took a while but, the saws did the job.The pilot drill is a bit of trouble to keep tight and is is a bit of a pain in the backside. Use dome anti-seize on the threads and it makes it a lot easier to take the saws off of the mandrill. Once I got the good starrt on the hole, I took the pilot drill out and the saw cut the hole just fine.

They cut holes well but trying to change the cutting bit on the shaft is a nightmare. Also no matter how hard you tighten the center drill but it comes loose, best to just remove once the out cut is started. To swap cut heads required and heavy bolted down vise. an 18" rod and a hand sledge to loosen the bit.

The screw keeps falling out. after a few holes it gets harder and longer to drill holes on brick walls. I left the sds plus bit with the hole saw attached in my garage and some moisture got into it. (just ok plastic box) Now i cant change the bit out, i try dw 40, torching it, clamps. plumbing wrenches. spend hours. at one point my worker and i both tried. i ask seller for support and was told to tap-ing the connection. what?

My order arrived today with one of the five drill bits missing from the form-fitted box. I don't understand how that can happen, given that it is so obvious that the space for the fifth bit in the box is empty. Now I have to waste my time repackaging, returning, and ordering a replacement.