gonna mix my own portland cement...any tips??

[pa_of_6]

So tomorrow, the boys and I will be mixing our own cement using portland cement.

Any tips. I havent done this for about 35 years so forgot so much!

[fishtank]

Rent a mixer

[calgarychef]

buying washed sand and washed gravel is cheap or you can buy washed aggregate mix. Most expensive and easiest is the just add water mix in the bags. Incidentally you're mixing concrete not mixing cement . If you go to Burnco to buy bags of cement you have to ask for "Portland cement" because believe it or not they don't know what "cement" is....I got in a huge fight there last year trying to buy bags of cement .....anyway I digress. Mixing in a wheel barrow is ok for smaller quantities and works best with a hoe. Not the kind of hoe you pick up at a cheap bar...a gardening hoe. Although a good hoe with a strong hoe might be a good combination....I digress again.

I do 3 shovels of aggregate and one shovel of cement, mix it dry until it's well blended than add the water. If it's "self levelling" you added too much water.

Sounds like a lot of work, I'm glad my projects are mostly over.

[pa_of_6]

yes on the Portland cement
Yes on the mixer
yes on the lots of work
I wonder if a rented hoe would help mixing the concrete

Could be cheaper than my son"s labor.....no wait..thats free!

[LeroyvdH]

As per instructions given to me by one of the best bricklayer I've ever known..
Use a mixer
1 part water
2 parts Portland
3 parts sand
5 parts rock

water first
sand let get completely wet
1 part rock gonna help mix the powder
Portland
rest of rock
mix and adjust for desired consistency

[bcrams]

Originally Posted by pa_of_6

yes on the Portland cement
Yes on the mixer
yes on the lots of work
I wonder if a rented hoe would help mixing the concrete

Could be cheaper than my son"s labor.....no wait..thats free!

X2 also ratios given so far are too rich, 5 to 6 parts sand/gravel mix to each part Portland cement, in the mixer add an ounce of dish soap to each mixer full of mix for air entrainment. Will give an awesome finish.

[calgarychef]

Originally Posted by bcrams

X2 also ratios given so far are too rich, 5 to 6 parts sand/gravel mix to each part Portland cement, in the mixer add an ounce of dish soap to each mixer full of mix for air entrainment. Will give an awesome finish.

That's actually true about too rich. Its also true that within reason strong concrete is best. The dish soap is an old school idea that works, it's also really nice for mortar as it makes it stick to the brick a bit better...lets us non-pros lay bricks easier.

[Gramps.257]

Originally Posted by calgarychef

That's actually true about too rich. Its also true that within reason strong concrete is best. The dish soap is an old school idea that works, it's also really nice for mortar as it makes it stick to the brick a bit better...lets us non-pros lay bricks easier.

Every WOC ( World of Concrete) convention i have been to in the last 30 years has atleast one seminar that brings up this topic of adding soap to portland cement and it should be avoided as it weakens the mix. Its not a "old school trick" but more of a old scabs trick. To truly get a easier to work cement use the true old school method and use slaked lime (Calcium hydroxide) Ca(OH)2

[Grizzly Adams]

By the time you figure on getting everything together and the work involved, might be better just to get ready mix. gotta consider uniformity of the mix and the fact that it's curing, while you're mixing more batches, important if you're doing a larger project and have to finish it. There are ready mix companies that cater to smaller projects. Mixing concrete isn't an old guys project.

Grizz

[pa_of_6]

Well...poured the footings today...
Was hoping to do the floor tomorrow but there is alot of sand/gravel to put in and pack first.

its a fairly big slab...about 34 by 18...4 inches thick.
Its a floor for the barn lean to addition so there is no need for it to be super smooth.

Ready mix is a good way to go but very expensive.
I figure we will be able to do it for about 25% the cost