Concrete Curing Compounds

[n74tg]

Am trying to locate curing compounds to put on wet slab after pour.  Only one store in town sells it and it's $67 for 5 gallons.  As slab is 12x22 I don't need that much.

One guy at Lowe's mentioned the old-timers used to mix up a pound of sugar and 2 gallons of water and spray that on; then cover with visqueen and it will work just fine.

Can anybody confirm this home-made brew; or is the guy just full of hot air?

[JRR]

I don't know about the sugar, but the water and plastic covering, after initial setting and finish trowelling, is good.  

The idea is to prevent rapid drying of the "upper crust".   Keeping moisture on the surface ...either by wetting often ... or capturing the moisture with a membrane, ... or both .... helps for a more "even" curing throughout the slab thickness.  Try to keep the surface covered/wet for several days for best results.

"Wetting" = very fine gentle spraying of water ... no heavy (abrasive) spray for the first day.

[bartholomew]

I'd skip the sugar. If I remember right, it actually interferes with the concrete curing process so it doesn't harden. Old-timers used sugar on the surface so they could brush it off later and be left with an exposed aggregate surface.

[peg_688]

Molasses was / is used can be to act as a release agent to expose concrete for a aggragate finish. Generally pea stone is the aggrate in the concrtete mix that is to be exposed. Gee I said exposed what will Glenn think / do :-/ Post his flashing photo ,   Again

  So is that your question ? Or are you looking for a curing agent??

[n74tg]

Peg:
I am looking for a curing compound (that preferably I can buy locally in 1 gallon size containers).

If I don't find any this weekend, I will start looking up concrete contractors and see if they have any they would sell me a small quantity of.

[peg_688]

The sugar deal would be for exposing it , here's a site with some other produces ,

 http://www.4specs.com/s/03/03-3900.html

 So your trying to cure it slower? Seal it ?

 I still don't quite understand , maybe one of the product's listed will meet your needs.

 PEG

 

 

[glenn-k]

Home Depot or just about any building supply should have Quikcrete concrete cure and seal in the one gallon size.

Water and plastic will do fine as far as curing goes - it won't seal it though.

[bil2054]

Hey, nt4tg.
Can't recall but once ever using a curing agent for concrete. A couple floors got sealer after the cure.
Prestress company I worked for (briefly) used steam, but I don't guess that's what you're after.
Last pour I worked on was a slab for a 30'x30' shop.  Truck came early morning, three of us pushed it around, screeded it, and floated it.  After it set, towards mid-late afternoon, the power trowel came out.  A few squirts of water and a couple of cheapo tarpaulins over night, and that was as flat and shiny a chunk of concrete as you could wish for.  Started framing a couple days later.
The one project where we applied a curing agent was when we poured new decks aboard a ship.  That was alot of area, and some odd shapes, so wetting and covering wouldn't have worked very well.
Anyway, I guess the point is unless the project is very large, to the point where covering it up is not practical, or there is some critical surface property desired, at least traditionally there wasn't much call for special curing agents, and so, as you have found, it is mostly availabe in commercial quantities.
As Glenn mentions you should find the Quickcrete product, but I honestly don't know that it would provide a better cure and finish than proper troweling and wetting.  I would be inclined to finish "traditionally", then maybe use a sealer/stabilizer after the concrete cures naturally.  Some of the epoxy finishes are amazing.
This is, as always, IMHO.  Should you be caught, the Secretary will disavow all knowledge of your actions. [smiley=wink.gif]

[peg_688]

 I agree with Billy bob , I have  never used a slow curing agent. I have wet down , in summer (hot weather) and I mean 90° plus heat , concrete for a day or so .

I've added 2% calicum in cold weather( speeds up the cure / working time , "kicks off" faster, ) and have covered slabs / driveways with plastic and hay to protect from freezing in - 32° weather.

 Every thing in between no added measures where / are taken . Maybe a plastic cover if it rains sooner than weatherman said it would  

 I do live in the PNW, when I lived and worked in R.I. I don't recall using a curing agent either 25 years ago so I could have forgotten  ) so if it is common to use a slow curing agent in your region due to intence heat it should be avaiable,  like Glenn said,  in a normal H/D , / lumberyard / building center.

 [highlight]If it's that hard to find , IMO , it's overkill.  [/highlight]

   G/L PEG

[tech-ad]

n74tg

I have heard that to get a hard surface on concrete, old timers used ivory soap flakes.  After the concrete is reasonably surfaced sprinkle a small amount of flakes on the surface and work into the surface.  If too much soap is used, the hardened surface may spall off and you are worse off than not using anything.  As usual don't overwork the surface or you will get segregation of cement from the concrete.

Concrete truck drivers used to carry a 5 or 10 pound bag of sugar to add to the mix if delivery was not possible.  Sugar essentially arrested the cure so the driver could make it back to the plant and dispose of his load.  It reduced jackhammer use.

Test it using a small batch of home mix from a bag on something like a patio block.  Make one with the soap and one without to see the difference it makes to the surface.