On Feb 12, 5:53*am, Davej wrote:
I've heard that hitting rebar with a diamond blade can quickly ruin it
-- so what do the experts do?


Good quality diamond blades and core bits will cut through rebar with
little more effort than concrete alone.
Water cooled is the way the pros do it.

The concrete cutting contractor that I've been using for nearly 20
years has cut through all sorts of messed up RC for me.

When Marty cut mounting holes for me in a chuck of concrete we hit a
#9 bar that was misplaced.
The 3" core bit bisected the bar such that I have (somewhere in my
"that's cool" stuff) a chuck of #9 bar about 2 3/4" long with the
inside diameter of the core bit curvature on both ends of the
chunk.

The floor of my lab was 24" thick with 2 mats of #6's at 12" o/c both
ways. To install a huge piece of machinery we needed to cut an access
hole in the floor. It was cut by another contractor using a 60"
diameter saw.......rebar didnt even slow it down.

Hilti water cooled core bits (vacuum base drill system) can core
concrete with rebar as fast as you can advance the bit (within
reason) .....12" hole in a minute or two.

What are you trying to do? demo? remodel? slab crack control?

cheers
Bob