I can’t get a ready-mix this saturday, so I’m stuck mixing my own concrete. The wife wants a Cabana for the pool, so I’m doing slab on grade, approx 7’x9′. I can at least get a little mixer, but I’m unsure about the mix. I seem to remember 3 sand 2stone 1 portland. Yes/no? Also, someone once told me a little dishsoap for air entrainment. Does that work or am I into a whole engineering problem?
K.I.S.S. Keep it simple stupid
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Replies
YES
Yes, 321 works, and dishsoap is O.K. ? or Yes, your into a whole engineering problem?
Karp, that is a lot of concrete to mix in a small mixer. More than two and a third yards at 4" slab thickness, that's more than 14 bags. I sure hope you have some help. My little mixer uses 1/6th bag at a time, using 3,2,1 formula, so that would be 84 loads plus! Maybe my math is off, but that's not a job to try alone.
The mixer I'm renting is a bit bigger and help "should" be there. I've offered the standard bribe of beer and bar-b-q. But getting back to my mix, you have also used the 321 mix ratio? And do you know anything about dishsoap for air entrainment? Someone told me that years ago, but I've never tried it.
if you have all that help, it be alot easier pushing wheelbarrow than, shovel, weight, sieve, mix, add water, shovel some more , wheelbarrow, finish
9 ft. by 7 ft by .33 ft. = 20.97 cu. ft. That's about 3/4 of a cu. yard, not 2 1/2 yds.
Yeh, I thought that seemed like a lot - Forgot to divide by .3 Thanks
You shoulda been there when we poured a bathroom roof in Mexico. The "sand" and "gravel" (read fine "caleche" (sp?) and coarse "caleche") were dumped in the street, and we hauled the stuff in in 5 gallon buckets. I forget the exact mix, but it was a fair-sized gas mixer, and I can't recall if it took a half bag or a full bag of cement with the mix. The guy sure mixed it wet, but he knew what he was doing.When it was mixed it was schlepped to the roof again in 5-gallon buckets, half full.Musta been about 12 of us (including maybe 4 ladies), and it took around 3 hours for the roughly 10x20 foot roof. Woulda gone a bit faster, but one limiting factor was how fast we could fill buckets from a garden hose that ran at barely a trickle.
If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
Holy Shid! I did a whole cellar floor of 3 stone 2 sand and 1 cement. My bad!
be eek but 7 years later there still ain't a crack in 'er.
A bird does not sing because it has an answer. A bird sings because it has a song.
I hand mixed my foundation:
3 stone
2 sand
1 portland
whoops.
measured in 5 gallon buckets
its still there & solid, but I have an aversion to mixing concrete now - maybe it has to do with age or wisdom...
Treat every person you meet like you will know them the rest of your life - you just might!
I had an old Sears monster mixer that weighed a ton that sounded like a tank attack but was glad to have it.
5 gal buckets and you deserve a medal or something.
be but we poor folk git 'er doneThe bitterness of poor quality remains long after the sweetness of low price is forgotten.
I posted before I edited - the 5gal buckets were to measure gravel/sand/cement. I had an electric mixer - for sale now, btw...
I'm still poor folk, but I have a nice house & equity
Treat every person you meet like you will know them the rest of your life - you just might!
I had a shovel.
"What was that again? Did I already add 2 sands?"
be 'best add a bit more cement.'
I kept all mine on the dry side and vibrated.
I see some of these mixes coming down the chute out of the trucks and it's so liquidy it's no wonder the basement floors all crack.The bitterness of poor quality remains long after the sweetness of low price is forgotten.
I had a shovel.
Missionary friends of mine report that in Mexico they laid block, mixing mortar in a pile on the ground with a hoe. It can be done - the best way to get rich is visit the third world and realize how much you already have.
My flatwork has never cracked beyond the hairline (I'll claim luck before competency) But we had a difficult pour this spring where the driver mixed very wet to make it run down the chute - the top 1/8" flaked off in places 2 days later.
Treat every person you meet like you will know them the rest of your life - you just might!
Reminds me of a picture in George Nash's book 'Renovating Old Houses' where he and one other were standing with shovels in front of a large pile of cement, the cement sitting on a large tarp.
They had just finished mixing the whole thing by hand with shovels on the tarp.
be sometimes ya gotta do what ya gotta doThe bitterness of poor quality remains long after the sweetness of low price is forgotten.
>>They had just finished mixing the whole thing by hand with shovels on the tarp.<< I've been told that mixing small batches of bags on poly or a tarp works rather well. I think the idea is that you put the mix in the middle with the water and then pull up the edges of the plastic and kind of roll it around to mix it. I tried it once or twice but couldn't seem to get the hang of it.
I've mixed a slab's worth by hand myself with an electric mixer. I'm a little older and a lot more wiser now. Also, as long as you meet the minimum yardage, you aren't gonna save much, if any $ by hand mixing bags.
Going the stone/sand/cement route, which I have done too, is as close to doing prison labor as I want to be. No thanks - I'm all grown up now.
Yep, we did that too, for smaller batches. They did it kinda like the old scheme for mixing mortar on a board or in a barrow.
If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
When you go to the gravel yard to get the aggregates, see if they have what is called "reclaim" here. Recalim is the concrete aggregate mix that comes back in trucks and the cement is washed out of it. Great premix and cheap if you can get it.
Also try getting the aggregate already mixed for concrete - can get that at the yards here.
My method for a 3-1/2 cu ft mixer is to put the bags of cement on the ground and back the pickup up to the mixer, throw 10 shovelfulls of aggregate into the mixer (use a sq;uare shovel for accurate repeatable shovel-full sizes. Then a shovel full of cement, add water for corect slump.
For a cabana, 2" on a good base is likely sufficient for the floor., unless you are going to drive on it as a 2nd garage?
when it comes to mixing concrete. I will not do it. I rather pay the extra and get a truck. ten hours running a mixer not my time.
ask for reclaim here and you would find yourself with ground up asphalt road top.
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You say you can't get a truck? Then how about the places that sell "A Yard at a time." They mix to your specs then send it home with you towed behind your truck in a tippable (sp?) trailer.
As others have said, you'll need help because it's going to take you more than one trip. Your buddies will have to do the distribution and flatwork while you go fetch some more.
Whenever I have a small pour to do.............when it's not worth getting a truck.........I use a small electric mixer and the bagged concrete mix from Homers.
No guessing the right mix, easy to handle, you can control the speed of spreading it out, etc. More people the better, but what a pain to mix one of these, 3 of them, oops, how many did I put in????????
Fuggedaboudit, cut the freaking bag and dump it in. Good to go.
Rod
cut the freaking bag and dump it in. Good to go
True, but I've found the shovel it out of the truck is actually faster at about 1/2 the price.
Of course, if you don't want to scratch up the bed of your truck.......??
FORGET the soap!
Edited 9/15/2006 7:33 pm ET by junkhound
Damn skippy!
I got the sand and stone free from the jobsite, gotta buy 1 or 2 bags of portland. Why no soap? seemed like a good idea.
Why no soap
Your original implication was that you would use dishwashing detergent.
You want something that makes bubbles BUT does not contain fillers that could interfere with the cement to stone bond.
Commercial DW liquids have who knows what additives that could interfere with the bond.
You could use homemade sodium stearate soap OK. 1% soap reduces the concrete strengh about 5%; you really want to use it only if you have a lot of freeze/thaw cyccles where you are.
You should get at least 3, preferably 4 bags for a 3-1/2" slab.
Some possible air entraining agents are:
Hercules Neutralized Vinsol Resin (NVX)-dry powder.
W.R. Grace Daravair 1000-liquid
ALCOLAC-Siponic-liquid
WA. Meadows double strength-liquid
Hoechst AG-Hostapur OS
Hill Brothers Chemical Co., Hico 303
Hill Brothers Chemical Co., Hico 315
Schaumbildner auf Proteinbasis, Protein based foamer
Natriumlaurysulfat, Sodiumlauricsulfate
Olefinsufonat, Olefinsulphonate
Polyglykolather, Polyglycolether
Sodiuoleat
Witconate
Yes but speed and price aren't everything. Ease and quality control have value also.And how much are you going to save on a small project......................and then ya gotta go to quarry and get materials................and then to the mason store to get portland cement.By the time you get back with everything , I'd be sippin margaritas while waiting for the concrete to dry.Nope. Speed isn't everything.That's what the wife keeps tellin me! Rod
By the time you get back with everything
Ah, there is a trick to making the time shorter - never make a trip for just one item! The barn usually has a stack of cement bags (bought when a discount was available) waiting for the next job, and a few yards of recalim under a tarp. Kidder stated he already has his aggregate from a previous job site.
Imn my case, a quick loader scoop into the dump truck (tilted bed easiest way to shovel out the mix, even faster than out of the loader bucket) and all of 5 minutes has passed.
The money saved buys the beer or margaritas! <G>
I,m still going call the truck even if I have to but two yards minmimum.
No going to lowes for mix
no having sand to clean up.
no renting a mixer
no cleaning a mixer
no returning a mixer
no cleaning the sand out of truck
no hauling empty bags off just a phone call and done 45 minute later. worth every penny.
The barn usually has a stack of cement bags I got a 143 sacks in my shed, right now.
Yeah, but really now. How many of those sacks are good?
I've been caught in too many cases of using old ceement, even keeping it indoors and dry, having become too hard to use.
they were free
were they brown?
be baggedThe bitterness of poor quality remains long after the sweetness of low price is forgotten.
no, there a contractor that build Lowes Building. He will have everything he needs on site the first day. trucks of everything. He will order more than he needs so he doesnt run out. Turn key 38 days. that building. parking lot everything. whenb he done he will give everything left over away. dont have tto pay to get it hauled off.
poured a bunch of fence posts this summer with a garage full of 80# lb bags that were 1-2 years old
Had to use the flat side of a hand sledge on the outside of the bags before i poured them in the mixer. It broke them up nicely though, everything turned out fine.
For a 9 ft. by. 7 ft. by 4 in. slab, you need about 32 80# bags of concrete. At Lowes, you can get concrete rated at 5000 psi for about $5 a bag. If you have a mixer, you can mix that amount in 1 or 2 hrs.
50 80# bags by myself (that whole pallet), and return the mixer, in three hours.
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Forrest
We have a concrete company here that is called Short Load that will come out with 9 yards of concrete in a dry mix and a water in a tank.
They have a hopper at the rear of the truck and they will mix whatever amount of concrete you need on site.
busta
I can make gravel out of rocks too, but why would I want to?
Get a concrete truck. Rearrange your schedule if you have to. With that size piece of concrete it will save you about 10 to 15 hours. Another consideration is that you won't be able to mix it as fast as it dries, so the first part you pour will be setting up before you are half done. The project will not come out with a professional look with site mix concrete. You will have the same problems even if you use bagged mix, with the added delight of a sometimes non-uniform bagged product.
Its too late , sat. morn, I'm at it. Gotta go, bye
well....how did it go?
Sorry, I was cleaning up subscriptions and noticed I never answerd your post.
Anyway, dry mixed everything in the driveway, sized for the mixer, loaded into barrel, back of the house to where I put the mixer, (right by the slab) mix and dump right into the form. Whole thing took about 4 hrs. Not including the time to get the mixer rented. All in all, not to bad. looks great and its been about 5 mos. !!! On accounta' once I finished the bastXXX, I never wanted to think about it again!!
So, how did it go? How did it come out?
BTW - sometimes negative reinforcment of an idea just emplants the determination needed to get 'er done. :-)
Just splained everything to Brian, sorry for being tardy.
B.F.N.