JACKHAMMER EXPERIENCE?

Rental equipment stores have different size jack hammers from hand held electric, pneumatic and small hydraulic units mounted on Bobcats or large units mounted on back hoes. Do you really want to buy one? Most rental places rotate equipment and it is maintained so they don't have to do field repairs that are a lot more expense for them than making sure it's rental ready at the shop. Might consider purchasing a used unit.

If you have any trace of carpal tunnel syndrome, or just aren't built like a gorilla, any of the hand operated units will do a number on your arms. A rental Bobcat with a hydraulic breaker is much more powerful, can work at angles you can't with a hand unit, and best of all you get to run it from a comfy seat, isolated from the hand numbing vibration.

I got quite a few hours with an electric HF jackhammer. I thought the blows it delivered seemed a bit soft, like hitting a chisel with a hard rubber hammer instead of a steel one. It did okay on red basalt, struggled occasionally through some harder 'blue' rock. Concrete or limestone should be easy enough, but granite definitely not. The tool was easy enough to hang onto and maneuver. I worked it at angles from vertical to near horizontal, using my knee to kick the pointy end out to where I needed it. The angle of attack had to be changed continually on stubborn rocks. Forget the cart idea.

In the past I have just rented a Bosch. It worked well for the concrete but a word of caution, the rental yard charged me to re-sharpen each bit when I really didn't need more than one of them for the task. They claimed that they had to be re-heat treated every time they were dressed hence the charge.

I think you would have to have an awful lot of demo work to justify purchasing one of these tools.

Might not be pertinent, but I had a solid limestone outcrop in the way of a home sewer line at my former home. Had to make an opening through the rock roughly 2' wide by 5' high by about 8' long. I borrowed a pnuematic jack hammer, an Ingersol Rand rock drill and a

150cfm compressor from a friend. The jack hammer made little or no progress. The rock drill worked pretty well at drilling, but making swiss cheese of the rock did not really speed things along. It was a bitch to hold at an angle on the rock face as it weighs about 100 lbs and the drill steel was about 3' long, it also made a clouds of rock dust which went everywhere.. Next I tried expansive concrete put into the drilled holes to split the rock. This worked, but was painfully slow. Called a Blasting company, but one look at the site and I was told it was it too close to the house. Next I rented a track hoe with a 2000 lb hydraulic breaker hammer. This made quick work of the rock and also was able to break it up into nice sized chunks I could move out of the way with my backhoe. Well worth the $600 rental fee which included delivery.

PIM,

Thanks for the info. I wonder which H.F. model that you have?

You also say that I should forget the 'cart' idea. Why do you say that?

j/b

Pete,

Thanks but there are always better ways to do things, especially my 'things'. I have already bought the hammer.

j/b

RLM, as I said in my original post, I already bought the hammer

j/b

Oldjag,

Thanks for the input. How long is 'painfully slow' with the expanding concrete?

I am negotiating on a backhow but I need to break limestone now.

j/b

Might not be pertinent, but I had a solid limestone outcrop in the way of a home sewer line at my former home. Had to make an opening through the rock roughly 2' wide by 5' high by about 8' long. I borrowed a pnuematic jack hammer, an Ingersol Rand rock drill and a

150cfm compressor from a friend. The jack hammer made little or no progress. The rock drill worked pretty well at drilling, but making swiss cheese of the rock did not really speed things along. It was a bitch to hold at an angle on the rock face as it weighs about 100 lbs and the drill steel was about 3' long, it also made a clouds of rock dust which went everywhere.. Next I tried expansive concrete put into the drilled holes to split the rock. This worked, but was painfully slow. Called a Blasting company, but one look at the site and I was told it was it too close to the house. Next I rented a track hoe with a 2000 lb hydraulic breaker hammer. This made quick work of the rock and also was able to break it up into nice sized chunks I could move out of the way with my backhoe. Well worth the $600 rental fee which included delivery.

The jackhammer was like this one...

I borrowed it from a neighbor. He paid something like $250 on sale, when the regular price was $400.

A cart might work well if you're breaking up a 4" concrete slab. A rock more than, say, 6" to 8" thick probably is NOT going to crack through the way the concrete will. The bit will just make a little divot and not go any further straight down, so you'll have to chip away the surface at various angles to liberate little pieces. Zing! I don't see how a cart would let you aim the bit the way you need it.

Wear goggles! In fact, wear a full face shield if you want to keep all your teeth.

Thanks for that clarification, PIM.

j/b