Rotary and demolition hammers

[Boondox]

All sales hype aside, if I want to dismantle a stone and mortar chimney and drill holes for rebar in concrete and granite, which brands/models/types should I be looking at?

TIA, Pete

[AndyF]

My father in law bought a 1/2" Bosch about 4 years ago at Lowes and it has done a good job for both of us. We trade it back and forth depending upon who needs it. If I was going to use one every day, I'd probably look at a Hilti. I used to use one and it was great.

[GaryM]

I have a Bosch 7/8" rotary hammer. It works great for drilling concrete, but I have never tried it for chipping. I think it would be marginal for demolition. But I might be pleasantly suprised if I tried it.

[egon]

Can't help on type but would suggest renting to get an idea of size for the jobs you have planed.

Egon

[Phred]

I also have a bosch. Great drill and not to bad as a hammer. Of course its small.
But if you just want to let the mortar fly on an old chimney I bet it would do the job.

The rental idea is a good one.

Fred

[CJDave]

[img]/forums/images/icons/tongue.gif[/img] A few years ago I guy gave me a big SKIL that had a broken crankshaft in it. I welded up the crank and used that hammer for several more years before it broke again. It was the big SKIL electric model, and it made child's play out of drilling one-inch holes in concrete. I'm looking to buy a real good rotary hammer as well, and I know enough to NOT buy a "hammer drill"....it's not the same thing. That SKIL had a "free" piston about an inch and a half in dia that went up and down in a chamber and really put the slam on the bit. No "hammer drill" would even approach that. So, look at the unit. It HAS to have a crankcase with a piston and rod that causes a sympathetic action in the free piston which is the "pile driver" effect that gets you through the tough materials. [img]/forums/images/icons/crazy.gif[/img]

[BrianP]

I got a Bosche with their bayonet style (SPS?) chuck. I got it after I burnt out 2 Makita's with relatively little use. I like it. I was a bit worried because those bits are special and a lot more expensive than the regular jacob's chuck type, but you don't neet that many bits and these style never slip, so they may last longer. Plus I found a chuck that fits into a SPS chuck.

The thing to watch for chipping is that there is a drill disconnect setting. Mine only has a hammer disconnect setting, which I discovered after I bought a set of chisels for it. [img]/forums/images/icons/frown.gif[/img]

Boyoboy, it goes through hard concrete like cheese. [img]/forums/images/icons/laugh.gif[/img]

[GaryM]

<font color="blue"> Boyoboy, it goes through hard concrete like cheese. </font color>

You bet they do! I have a Makita hammer drill, big one, two speed gearbox and all, and I never had much luck drilling concrete walls. The Bosch 7/8 rotary hammer can drill a 1/4 dia. x 1 inch deep hole in about 30-40 seconds.

BTW, that bit locking system is called SDS.