Hello everyone! I'm getting ready to tear out a old slab (no rebar, about 2 foot footings) and remove a well pit. I purchased a Harbor Freight Jackhammer b/c all the good reviews but the job is going too slow. I called a local tool rental place that has a backhoe with breaker attachment for a good price. They even said it only takes about 5 minutes to change between bucket and breaker.........this sounds too good to be true but after an afternoon with the Jackhammer I need something with more horsepower. Has anyone here changed these attachments before? Should I look for a certain brand of hoe? (John Deer, Case, ect) Thanks!
An electric jackhammer from HF? I've used a couple of different NAME BRAND electric hammers, and they don't compare at all to the air power version. I'm sure any backhoe breaker you rent will be plenty, but what kind of shape are the slabs in? It might be quicker to lift the slabs and drop them to break into manageable pieces, especially if the concrete is old, weak and cracked even a little already.
The slab is for a old garage and approx 20ft by 20ft (cracked in places but largely intact). The HF Jackhammer is making good progress on my well pit (6-8" of concrete) http://www.harborfreight.com/15-amp-heavy-duty-professional-breaker-hammer-68147.html But on the garage slab I'm dealing with 2ft thick footings approx 1 foot wide that are largely intact (the rest is 4-6" thick) Could a backhoe tear through the footings?
A backhoe won't tear through the ftings but you can lift them up place something under them and drop them a few times or bang them a time or to with the bucket teeth.
Yeah, you might have to dig out one side of the footing and get into the right spot to lift up the footing, but those look pretty easy. Once you get it lifted up, drop it so it lands on some other concrete in the middle or both ends, it will crack right apart when it's not supported. The other question is what are you doing with the waste? if you want it broken up, for that size I might stick with the HF breaker, pry the broken pieces out as you go, and break off the next corner. Don't make it work so hard to punch a new hole clear through the middle, take a 3-4" square off of an unsupported corner and it will only have to chisel in a little bit before it breaks off. A pneumatic jack hammer will punch right through like you're trying to do there, but a Bosch will take forever too. I've broken more concrete than that with a sledge hammer, your HF breaker will do it fine if you want the stuff broken up small. If you're dumping it in a huge ditch, or whatever, then break it only enough to haul with the loader, use a chain if the pieces are too big to pick up with the bucket and get rid of it as fast as possible, if that's the goal.
I'm worried about breaking teeth on the backhoe. I dont do this for a living but 2 foot thick concrete doesn't seem it would break that easy? The debris is going into a dumpster I pay for (a few hundred pounds each trip).
Huh, what? by hand? Get the backhoe breaker or continue with the HF breaker as I described, if you want it broken up fine. Can you find a place that takes concrete free nearby? it can be recycled, used for fill, whatever. Breaking it by dropping makes nice big chunks that are the right size to load with the front bucket, it won't make it small enough to move by hand.
I'm working with a light duty pick-up truck so either way I would have to keep the weight down. Besides the landfills around me charge by the ton to dump concrete so I might as well use the dumpster I have. Either that or bring in a big enough roll off container? Are there usually weight limits?
Check with a local concrete plant, they may take broken concrete for free. They bust it up and use it for aggregate. Depending on how expensive the dump gets, (in Kali, they're insane; It's $40 for a full size pickup bed, cab high), I'd be thinking of finding something else to do with it. Run a Craigslist ad for 'FREE' concrete to make retaining walls; UP PICK UP! Or if you have the room, bury it.