Anyone used a Makita electric jack hammer?

[rick-l]

I wand to break up a 3 foot tall 3 foot diameter concrete cylinder. Will this do it and how long will it take?

This is the one Home Depot rents.

Makita HM1810X3 70 Lb. AVT Breaker Hammer - Sds Shank Bits - Amazon.com

[rusnak]

Is it a footing for a building or a light pole? If so, then there will be rebar in it.

I've used a concrete breaker from DeWalt that made short work of that. I'd say less than 2 hrs unless there is a ton of rebar. If it's a light pole base, then hire a Bobcat guy.

[pete3799]

The town I work for rented one. We were trying to get a culvert in and struck ledge. Didn't work well on that but I suspect it would work ok on concrete.

[rick-l]

It was a pier for a deck. I have three of them. Two of them landscape timbers sit on. I want to put in a concrete block retaining wall. It looks like they just dug a 3 foot deep hole and filled it with concrete.

No rebar. I took after the easy one to get to with a sledge hammer and after about four hours reduced it to a cone.

I was going to try to get this one out without removing the rotten timbers until I get the blocks for the wall.

[MikeSid]

An electric jackhammer will make pretty quick work of that.
If it is just dirt formed, there is likely no rebar and they didn't vibrate it. So it should break apart into large chunks pretty quickly.

Since you are renting, pick one sharp pointed tip to use. You may be charged for sharpening each tip you use, so pick the pointed one and stick with it. Use the weight of the hammer, eye protection and steel-toed boots.

Given the pic you posted and the way the ground lays, be sure to stand above the tip of the hammer. It may sound obvious, but don't have your feet below the level of the tip of the hammer at any time. Looking at the pic it would seem tempting to stand with a foot in the hole. For reasons which should be obvious, that's not a smart move.

[VincentVega]

I used a much, much spammer impact hammer for a ~2' square section and it mowed right through it. I would expect that huge breaker to take no time at all.

[look 171]

What's the retaining wall for? Structural, holding up a ton of soil or the new deck? Why not just build the footing of the retaining wall as part of that? Epoxy it to that big footing. Engineering involved, code requirement? A good size electric hammer will beat that thing out in 15-20 min, depending on how deep it is.

[rusnak]

I guess my question now is what are those landscape timbers for? You know that when you blow apart the concrete, all support for whatever it is touching just vanishes.

[rick-l]

That is a 3 foot high retaining wall that has a patio made of red bricks on top. I want to replace all the 45 year old landscape timbers with blocks and extend the brick part of the patio to replace some of the wood deck. When i get the new wall set up I'll take out the wood, build the wall, and back fill.

[look 171]

I leave it in there unless you have access to a hammer. Why rent or buy one just for that. Is this on a hill or flat? If its on a hill, then I take it out, if flat land, leave it and build on it. just dig under it for a stronger footing. There's no weight on the patio. I would do this only if its my own house because I know it will be sound and plenty strong, but never for a client. People didn't pay for that.

[vash]

There is an expansive clay you mix up and
pour into drilled holes. It expands and cracks apart concrete.


Sent via Jedi mind trick.

[rick-l]

Got all 3 done in under 4 hours (minimum rental). It doesn't look like it in the picture but that hole is 3 feet deep.
Thought about leaving it in but I didn't know what a Segmented Retaining Wall (concrete blocks) would do sitting on it.
I'm extending the retaining wall to make it a patio with pavers instead of a low deck

[look 171]

Originally Posted by vash

There is an expansive clay you mix up and
pour into drilled holes. It expands and cracks apart concrete.


Sent via Jedi mind trick.

What's is it called, more info? Sure makes demo so much easier

[Rednine11]

I used the 90 pound version of it and it was a lot to handle. 70 would be a lot better and probably break through anything you need