Fast setting concrete

[ICHTHYDEMON]

I'm setting some posts this weekend and the I'm considering the use of fast setting concrete. All you have to do is dump the mix in the hole and add water. The mix soaks up the water and the posts are set in about an hour.

Has anybody used this stuff?

[Bait O' Eggs]

you could do the same thing with regular concrete mix. Are you in a hurry? I would assume the fast setting concrete would cost a little more.

[ICHTHYDEMON]

I am in kind of a hurry. I'd like to get the posts set tommorow morning and the rest of the fence built in the afternoon. The fast setting mix is about $2 more per bag. If I can get my fence finished tommorow the extra $40 won't kill me.

[Bait O' Eggs]

I have never set post without mixing the concrete seperate and adding to the hole, but I have seen it done where you dump some concrete mix in the hole, add some water, dump some more mix, add water .......

I would assume if you were in a hurry you would want to mix the concrete first, because until all the cement is wet and hydrating, the concrete wont get hard. I would guess it would take time for the moisture to set off the reaction if you had to much mix between the water level. Adding to much water will weaken your concrete, but for a fence post I wouldnt be to worried about that.

And remember, flour is to bread, as cement is to concrete. Nothing worse than somebody calling concrete, cement. They dont call bread, flour.

[WaterDog]

I would mix it before it goes in the hole but that is just me.

And you don't "pour" concrete, you "place" concrete. :grin:

[Norm]

I have always just dumped dry concrete in the hole, add a little water about half way then more when it's full . I have never had a problem with loose posts. If it's not a retaining wall or soft ground, I doubt you need 3K test concrete. With a 8" hole and a 4x4 it takes about 2/3 of a bag per hole. I always make a mound on the top to keep water from puddling around the post. I imagine the fast set just has a little calcium in it which reacts to the cement and creates heat for a faster set. Hot water will also help speed up the set.

[skahorse]

All I can say; Take the time to do it right. You can do whatever you want, but I wouldn't want to be messing with posts again in another year.

--Skahorse

[Uglygreen]

Its fine. How fast it goes off depends on temprature. Use hot water or add some calcium chloride and it will go really fast. And FYI you "place" slabs and you "pour" footings and foundations. Pour is the correct term for this application.

Brad

[ICHTHYDEMON]

All I can say; Take the time to do it right. You can do whatever you want, but I wouldn't want to be messing with posts again in another year.

--Skahorse

I don't want to do it again either,thats why I'm asking. The fast setting stuff has a higher strength than run of the mill concrete.

[kamloops]

Just cause the mfg. says the concrte is fast setting does not mean any greater psi than the usual homeowner 3000lb pea gravel mix you get at Freddys.
I am aware of a local mfg. that sells a 5000lb concrete mix but you don't need it for fence posts.
All you need is a mass of cured concrete that holds your post upright. As long as the concrete cures and you have
enough in the hole your good to go.
Most fence contractors mix their mud and wheelbarrow to the post hole.

[WaterDog]

Brad, BOE knows what I'm talking about since we went to the same school. Well sorf of.

[baltz526]

if you use screws and fence clips for all the fasteners you can use any concrete mix and start fencing immediatly.

[texas bass]

Fast setting concrete is quite a bit more expensive. I used it on a flagstone patio and had some cracking problems. But don't know if the same thing would happen with setting posts. I would just use the regular stuff.