Thread: mixing 1m3 by hand/wheelbarrow?

theres about 6 full barrows to the metre3

Its do-able, good job for a cool day

Sorry to ask but why would you put a slab beneath a water tank.
They are best on a sand base.

I'm gett'n a bit old and weary to want to mix that much by hand, but certainly doable.

A few tips to make it a bit easier if you don't know: Don't just shovel all the gravel, then all the sand then all the cement and start adding water.
Shovel the ingredients into the front of the barrow, alternating between gravel, sand and cement but leave the back half clear. 3:2:1, 3:2:1, 2:1:1 should be a full barrow. Then put all the water in the back, about a bucket. Then with your spade or larry, take narrow vertical slices out of your mountain of material, and get it all saturated before you take another slice. This way the mix only gets stiff right towards the end.
If you just throw everything in and throw the water on top then you've got to battle with it from the word go, and it will take you twice as long to get it all mixed thoroughly.
It's a good idea to lay some cheap plastic down under the slab to stop the mix drying out between barrows. Cold joints could lead to cracking.

I mixed about half a cube in three goes, a few years ago using a big piece of Fortecon. Shoveled my pile on one end, lifted the plastic and walked away, pulling the corners in as I went. Then went back the other way and it was dry mixed. Added the water, dragged it once more and it was done. Quicker and easier than a barrow I reckon.

A good tool for mixing in a barrow is a garden hoe . A Chop Hoe , not a push hoe .
Stand at the head of the barrow , as opposed to the handle end , and with the hoe , pull the mix straight up the middle , up the slope . Add the watter bit by bit , till you get it just right.

As for pouring the slab in two sections , yep , no problem .
When you get to the center , or wherever , just slot in a stop-end , pushing it down to the mesh / re-bar , and nail it to the boxing .
Drive a peg or two along it's length . Off-cuts of re-bar will do , easy to knock them in below the mesh , rather that pull them out later .
The small amount that oozes out below the stop-end is nothing to worry about.
The reinforcing steel will hold the slab together ...thats' it's job , after all

And pour a 75mm to 100mm thick slab . 50mm is too thin .

Jock

If you seriously want to do it I would bypass the barrow and do it on a big sheet of tin, mixin concrete in barrows is good for taking skin off knuckles but not so good for getting a consistent mix easily. Mix it dry first, then add your water before mixing that through, you will get a more consistent product more quickly that way.

We used to work on one cubic yard being 27 cubic feet and 3 cubic feet to a wheelbarrow, that's 9 wheelbarrows to a yard., Say 11 for a cubic M. Unless of course Bob's got hungry boards on his barrow. Concrete weighs about 2.4 tonne per cu M. Work it out.

Personally I wouldn't mix it in the barrow. On a flat bit of concrete, a couple of sheets of ply or whatever clean patch of ground, with a square mouth shovel.

Mix it up dry, sand and cement first then slowly add water to all the time turning it with the shovel.

If you must do it in the barrow, the old plasterers used to use a thing like a hoe, with a hole in it, and that made it a lot easier that a shovel. I have used a mattock for the same, but only for the odd barrow or two.

A sand bed sounds awfully temping eh?

cheers
Bill

Originally Posted by billbeee

.........A sand bed sounds awfully temping eh?...........

And it's actually the preferred base for a water tank.

Mick

Top response guys. Thanks for the input.
Re the sand bed, the tank is a bluescope tank which is basically sheets of moulded tin riveted/screwed together and then about 30 tubes of silicon to seal the gaps. I know it aint the best but its more than half the price of concrete, full plastic and even the better grade steel tanks which have bladders that can be replaced. All the above come in at round $4500 for 20 000 litres while the bluscope is $2000 for 17400 litres.
I have two concrete tanks for house and this third is for the vegies + outdoor bath so... Also it has 20 year warranty the same as plastic tanks and the better steel ones.
I spoke to the bloke who builds them and he said concrete slab or timber base. he wont warranty it against anything else because any moovement at all and the silicon comes under stress etc and sand might settle too far or shift and he also said that when you are trying to place it it is difficult to put the tank in place without walking over the sand bed making holes etc...
I wanted a blue metal base boxed in but he said no to that too.
Thanks again. Bloody quick too to get help here isnt it

Originally Posted by billbeee

Unless of course Bob's got hungry boards on his barrow.

He must also have muscles in places I don't. I usually go 8 barrows per cube out of a premixed truck but if your mixing it yourself it would be easily 11. I wouldn't even think about it without a mixer.. because mixing up in a barrow is about as thrilling as digging holes by hand in clay.

Also guys - while on topic.
How clean does my metal have to be?
I have almost enough laying out on my driveway which i need to shift as im putting a slab there one day. Its very clayey, loads of small sticks and small loose bark. Will that be fine to shovel up and use? Or should i go some fresh stuff?
And what qulity sand? Good sharp brickies sand or as its only a water tank base can i use some au natural grainy river sand off the side of the road and maybe giving it a light sift.
Im sure your getting my modus operandi here. Dont mind the labour mixing in a barrow. Dont mind the labour loading up the trailer with sand, dont mind the labour scraping up about a metre of mertal.
bear in mind i live aways outta town and its far easier to drive down the road and load up the trailer than it is to drive into town and get them to dump a load onto my trailer.

Originally Posted by billbeee

We used to work on one cubic yard being 27 cubic feet and 3 cubic feet to a wheelbarrow, that's 9 wheelbarrows to a yard., Say 11 for a cubic M. Unless of course Bob's got hungry boards on his barrow. Concrete weighs about 2.4 tonne per cu M. Work it out.

always worked it to be about 12 barrows to the m3, more than 1/2 a barrow load of concrete is too much for me to be moving too far these days )

Originally Posted by Bleedin Thumb

He must also have muscles in places I don't. I usually go 8 barrows per cube out of a premixed truck but if your mixing it yourself it would be easily 11. I wouldn't even think about it without a mixer.. because mixing up in a barrow is about as thrilling as digging holes by hand in clay.

next time I need to dig a hole in clay then fill it with concrete I will remember to get you over here, I'll dig the clay )

Originally Posted by journeyman Mick

And it's actually the preferred base for a water tank.

Mick

yep, as the tank fills it makes an impression in the sand, that helps the whole bottom to support the weight.
(edit, seeing as how it is a metal tank, I would use a timber base with a small gap between the boards, like decking, rather than concrete or sand base)

I've mixed concrete in a barrow and it's hard work, i'm not sure where you live but I would forget the barrow and hire a cement mixer. The hire charge wouldn't be that much and you would only need it for one day and your back will be most greatful.