Common raw material:
a. Cement, sand and small stone(stone powder)
1. 10% cement in weight, 45% sand and 45% stone(stone powder)
2. 10% cement in weight, 30% sand and 60% stone
Note: cement quantity you can adjust according your sand and stone quality. Usually from 5-12%. If stone powder
have big stickiness, you can add more sand and decrease cement.
Water:
Mixing dry material about 30s is better, then shower water little by little.
Below video will show you how many water need to add
You can also use fly ash, construction dustbin or other material as concrete hollow block raw material.
New video show you how much water and cement need to add in mixer
Brick machine expert answer: