On Oct 6, 2:24 pm, willshak wrote:
X-posted to other relevant group.

Before there were concrete drill bits, or electric drills for that
matter, small round holes in concrete or rock were made by a round
chisel type tool that was pounded into the stone with a small sledge
hammer while turning the tool. It might have been 8" or 10" long. The
face of this chisel had a star-like pattern, only with 4 points, like a
plus sign " + ". I believe it was called a star drill.
A Google search brings up a lot of sports drills (training regimen).
Anyone know if they still make them, or if so, where to get one on-line?
I'm trying to drill some 40 - 3/4" holes in concrete and my 1/2" corded
electric drill with a concrete bit stalls on the stone aggregate in the
concrete requiring me to stop and try to crack the aggregate with a
large punch. I figured a star drill would work better.

--

Bill
In Hamptonburgh, NY
To email, remove the double zeroes after @

You didn't say (or I missed) how deep the holes needed to be.

But even shallow 3/4" holes will take some time to drill 40 with a
start drill (basically a hand operated masonry drilling system)

Rent (or borrow) Hilti or Milwaukee rotary hammer....either will make
short work of 40 3/4" holes.

A regular drill motor & a concrete bit will take FOREVER (BTDT) use
a rotary hammer, fast & easy.

Don't bear down on the tool, let it do the drilling & you'll be done
in a few hours depending on hole depth.

cheers
Bob