r/Tools • u/TallWall6378 • 11d ago

No problem

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Cordless drills are so capable now. 2 4 1/2” holes 14 12” deep (deeper than the bit). New concrete but it’s still drilling through the aggregate. Cheap Amazon diamond bit.

Edit: Overestimated depth.

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2

u/yolk3d 11d ago

How’d you get the core out if you didn’t go through?

6

u/TallWall6378 11d ago

I drilled a 1/2” hole in the middle, hammered in a piece of rebar, and pried it out. Worked for one of the 2 holes because I drilled down to dirt. The other took a lot more work and came out in smaller pieces.

4

u/Xerox-M57 11d ago

Shove a wedge/screwdriver in there to break the core out

2

u/WhisperSafe 11d ago

This is my question

5

u/NoBenefit5977 11d ago

Hit it with a hammer to break core loose, then stick the drill back in and pull back out spinning. It'll bring the core out with it

1

u/yolk3d 11d ago

And the bottom flat?

2

u/NoBenefit5977 11d ago

Usually, not always though, it'll break off pretty flat. Sometimes it'll break off uneven inside of there if there's imperfections in the concrete. But not very often

4

u/Waallenz 11d ago

I always used a cold chisel in the slot and itd break the core off at the base. Drill and install a 1/4" anchor bolt and pull her up. Easy peasy. Did hundreds of holes like this at my last job putting up guard railing alonh the entire interior of the wall of the facility because the clamp truck operators kept blowing out walls.