Making concrete blocks

The concrete blocks are necessary for many construction projects, particularly those outside, as fences and walls. You can buy concrete blocks to different manufacturers, but if you need them tailored for specific projects, or if you just want to save some money, you can do it yourself. Home blocks can give profit if you do for sale. Once you master it, the process is not difficult.

Instructions

  1. Place the molds of concrete in the way you want the remaining blocks. You can buy in different stores or make them yourself, using bricks or stones as models.
  2. Use a cement mixer with clean sand. The ratio should be 3 parts sand to 1 part cement to normal concrete classes. For a stronger concrete beam mixing 2 parts sand to 1 part cement.
  3. Add gravel or limestone to the mixer. The amount of gravel should be almost equal to the mixture of sand and concrete: 3 parts gravel to 2 parts sand, 1 part cement. You may need to experiment a little; too much gravel, you cannot achieve a consistency smooth on your concrete.
  4. Add water slowly, stirring until it reaches the right consistency. You can control while stir mixture, removing a sample with a shovel and put a little on the Abrams cone, measuring how the mixture sits. When seated around 3 to 4 inches (7.5 to 10 cm) in the cone, the mixture containing the correct combination of ingredients.
  5. Continue concrete mixing for several more minutes until the whole mixture becomes consistent.
  6. Spray the inside of your mold with a water-based product to unmold concrete. This allows you to remove the concrete block once it has hardened.
  7. Pour the concrete carefully into the mold, then level the top mason using a shovel or a wooden board. Hit a little mix to settle and eliminates air bubbles that have in the mold.
  8. Allow the concrete to dry at least 24 hours before attempting to remove the mold. Then press down the entire mold while pulling up block. The block must be left alone and can be used again to make more blocks.

Tips & Warnings

  • Once you’ve put the concrete into molds, clean everything quickly. Concrete is much easier to remove from clothing and equipment when it is still wet.
  • Always wear protective clothing and cover your nose and mouth while you mix the concrete. The smell is usually very ugly and a respirator prevent any kind of dust aspires.