Perhaps I'm swinging too hard or hitting at the wrong angle since the concrete is at foot level, but I've now broken two 8 lb sledgehammers trying to break up the concrete. And I didn't make much progress before they broke either.
I've seen the expanding grout, but it says not to use on concrete that is this thin.
Would a heavy moving blanket on top be enough to stop chunks flying and possibly hitting windows, etc?
You may need to add some pre-defined failure points before breaking it up. Try drilling holes with a hammer drill to add more predictable break points.
Rent this:
In reply to ThurdFerguson (Freeloader) :
Yup
Both of the above would work. Remember, concrete has amazing compressive strength and really low tensile strength. So splitting it is much easier if you can get between two portions of it. If you have something roughly cone shaped ( like a swaging tool) that you could drive into a 1/2" hole about 6" from the corner of the slab, it'll pop the concrete apart very nicely.
Right now you might as well be splitting wood with that sledge, use a more appropriate tool and the job will be easier.
In reply to pilotbraden :
+3. electric jackhammer from local rental yard.
As yous saw on my build thread, to do my pool coping and grass, I had to break weeks of concrete. 4 inch thick. what @thurdferguson said is what worked for me. It is hard work.
I wished I paid some hispanic day labors to do it. My body hurt for weeks.
Looks like I'll be going to the tool rental place next week.
Thanks gents!
Rent this?
If you can pry them up so that they're supported unevenly they should breakup pretty easily. The idea is to support them and hit them in such a way that the impact flexes or bends the slabs.
I've had good luck with a hammer drill and a 3/8" bit. Just drill a bunch of holes in it to give it somewhere to break.
Another option would be to score the surface with a concrete abrasive blade (just use a metal cutoff blade in an angle grinder with lots of protective gear). That will give it a "fault" line... like if you're cutting glass or tile. Score it and it will break easier.
APEowner said:If you can pry them up so that they're supported unevenly they should breakup pretty easily. The idea is to support them and hit them in such a way that the impact flexes or bends the slabs.
In high school a builder showed us how to use a pry bar on driveways and get some air under them. Hit them with a smack and it'll break up. Of course that was 1978 Datsun310Guy.....
Curtis73 (Forum Supporter) said:I've had good luck with a hammer drill and a 3/8" bit. Just drill a bunch of holes in it to give it somewhere to break.
Another option would be to score the surface with a concrete abrasive blade (just use a metal cutoff blade in an angle grinder with lots of protective gear). That will give it a "fault" line... like if you're cutting glass or tile. Score it and it will break easier.
Don't have a hammer drill. Just a normal 18v Kobalt cordless. Are there good enough bits to use that, or is that still going to be a world of effort not worth messing with?
I've already spent $55 on two sledge's that snapped, so I think sucking it up and renting the jack hammer is probably going to be the best bet.
Although the exploding grout sounds fun to play with. 
In reply to z31maniac :
You want a hammer drill for that. A regular drill with masonry bits will mostly just make noise without much progress.
How close are the neighbors?
It's the only way to be sure you get all the pieces...
4th or so for Bosch Brut or the above pictured electric hammer. Be sure you get two bits because you can get one buried in the concrete. If that happens, remove the tool from the bit and go in next to the stuck bit with the other one.
Best method is to start the tool out vertical and as it digs in let it lay over toward you to about 75 degrees.
Source: I used to own a tool rental company and a Redi-mix concrete company.
Shotgun?
or is that just for lugnuts?
Curtis73 (Forum Supporter) said:I've had good luck with a hammer drill and a 3/8" bit. Just drill a bunch of holes in it to give it somewhere to break.
Another option would be to score the surface with a concrete abrasive blade (just use a metal cutoff blade in an angle grinder with lots of protective gear). That will give it a "fault" line... like if you're cutting glass or tile. Score it and it will break easier.
I'd look at using a masonry blade in a circular saw. A bit more protection than the angle grinder, but same idea to create a weak point.
I just busted up an old basketball net post set in concrete with my $10 air impact hammer aka air chisel. If you have compressed air it might be an option for you.
Stefan (Forum Supporter) said:Shotgun?
or is that just for lugnuts?
I thought that was just for removing wheels?
No Time said:Curtis73 (Forum Supporter) said:I've had good luck with a hammer drill and a 3/8" bit. Just drill a bunch of holes in it to give it somewhere to break.
Another option would be to score the surface with a concrete abrasive blade (just use a metal cutoff blade in an angle grinder with lots of protective gear). That will give it a "fault" line... like if you're cutting glass or tile. Score it and it will break easier.
I'd look at using a masonry blade in a circular saw. A bit more protection than the angle grinder, but same idea to create a weak point.
No circular saw and no air (wawazat).
I have ZERO tools for home/building type stuff.
Breaking stuff apart I can do pretty well by myself. It's the putting stuff together where I has trouble. 
Reminds me of the time I had a big Bradford Pear self-destruct in the front yard. I was able to get rid of the above-ground parts, but the stump was giving me fits. After a couple days of hacking at it ineffectively with a variety of tools, I paid a guy with a nifty stump grinder $75 and it was reduced to wood chips in about 10 minutes.
But yeah, if you have the means to haul it off, rent a jackhammer.
In reply to 1988RedT2 :
I have a stump grinder and sometimes people fuss about the cost to grind out their stumps. I'm tempted to hand folks an ax and tell them to give it 10 minutes of hard effort and then tell me my specialized equipment isn't worth the cost.
In reply to z31maniac :
Diamond blade for your angle grinder. I could lend you mine if you're not in a huge hurry. I know they're expensive, but damn are they resilient.
Anyway, that would make great relief cuts for you to them smack with a hammer.
In reply to KyAllroad (Jeremy) (Forum Supporter) :
Agree. I found the man's price to be very reasonable. He's got to purchase and maintain the equipment, he's got to bring it to my property, unload it, grind the stump, and reload it. Since he was kind of a friendly acquaintance, I wouldn't be surprised if he charged me a bit less than is customary. Seemed like a bargain to me.
You'll need to log in to post.
