This is my new green sand mixture. This one consists of 87% of sand and 13% of bentonite clay. And some water of course :) I think in some way it's little better than my last green sand formula which consist brown clay. Bentonite clay is very sticky and oily. It's very different from brown clay. And this time green sand is really green! :)
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Step 1: Bentonite Clay
This particular bentonite clay was as hard as a rock! For this green sand recipe we need 13% of clay or in my case 2,2 kg (5 lbs).
Step 2: Adding Water
I couldn't effectively crash it, so I decided to add some water.
Step 3: Sand
The next stage is to add sand. We need 87% of sand. I used 15 kg (33 lbs).
Step 4: Mixing
I couldn't mix clay and sand by hands, so I used a "heavy artillery".
Step 5: After Drying
After a week of drying the result is grate. It works grate for casting.