When you are mixing concrete you need to make the right mixture for the job of making concrete blocks. You want to make really good concrete which will form a solid, cohesive concrete block which will not crumble. To accomplish this you need to use the correct mixture of Portland cement,sand,gravel and water.
An excellent method for doing this is to make a wooden box 27 by 24 inches and 10 inches in depth. Then to get the right mixture use one bag of Portland cement and mix with it one boxful of sand and two boxes of gravel.
You can use a cement mixer or mix this batch by hand. To do it manually spread a tarp or a plastic sheet on the floor or do it on a sheet of plywood. Pour all the dry ingredients into a heap and then with a shovel keep turning them over till they are well mixed. Be sure that they are mixed well or you will not make a good homogenous concrete mix.
Make a hole in the centre of the heap and shovel the mix up round the hole. Then take precisely 14 gallons of clean water and pour a little at a time into the center hole and scrape the surrounding mix into it gradually. Gradually pour water into the hole till the whole batch is well mixed. Your concrete will now be ready for use.
Using a cement mixer of course makes the job considerably easier. You can put the same amounts of dry ingredients into the cement mixer the and turn it on till the ingredients are completely mixed. Then gradually add the water to the mix and run the machine till you have a smooth mixture.
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