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View Full Version : Core Drill Bit


pastor1189
Feb 23, 2013, 11:30 AM
Friend has to drill a hole in cement block. About 2" wide. Has a lot of masonry
drill bits and a hammer drill maybe the largest one drill bit is perhaps 1" wide and is long enough . But he would have to make two separate holes. If the core bits were not so expensive he could probably use that.. Is there a way to make the hole bigger to 2" wide? Or must he drill two separate holes?

smoothy
Feb 23, 2013, 11:56 AM
Have you tried an equipment rental place... I know the ones local to me have them. You don't need to buy something you will use once.

smearcase
Feb 23, 2013, 12:03 PM
I just did one through foundation block using a hammer drill and 1/2 inch masonry bit (drilling from inside) to accurately locate the center from outside. Then used a variable speed hammer drill with a flat bit from outside to enlarge the hole. A large core bit would probably still cause overbreakage where it exits outside. Once the small hole is accurately located outside, enlarging it gradually even with a hammer and chisel is relatively easy.

pastor1189
Feb 23, 2013, 12:05 PM
Very good thanks

ma0641
Feb 23, 2013, 01:15 PM
Use a smaller drill and make a circle of small holes. Then knock out the center. Make sure you are in a space not the web.

pastor1189
Feb 23, 2013, 01:28 PM
Okay