Thanks for that clarification, PIM.

j/b



"Poultry in Motion" wrote in message
net...
justme wrote:
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?

The jackhammer was like this one...
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=96035
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.

j/b


"Poultry in Motion" wrote in message
net...
Pete C. wrote:
RLM wrote:
On Sun, 22 Mar 2009 13:54:14 -0500, justme wrote:

Has anyone ever used a H.F. LARGE jackhammer AND a Bosch Brute
jackhammer?

I need to break up some limestone and harder rocks underground.

I already bought a H.F. unit but haven't gotten it yet.

Has anyone every made one self-supporting on a 3 or four-wheeled cart
whereby one didn't have to hold the unit?

Thanks

j/b
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.