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Southern Bentonite for Water Bonded Foundry Sand, 10 Pounds

Our Price: $28.00

Product Code: 1012-010


Bentonite Clay (Sodium Bentonite) is used as a binder in water bonded foundry sands.

What It Does:
  • Southern Bentonite imparts good strength to the sand when it is moist. This is important when first making the mold.
  • Western Bentonite gives sand good strength to the sand when it is dry. This is important for the mold to have strength after it has dried.
  • 50% Southern Bentonite and 50% Western Bentonite makes a good mix for both green (wet) and dry strength sand.

How To Use It:

Add water (1% to 3% by weight of sand) to the sand and mix.

Foundry sands typically use between 2% to 10% bentonite by weight of sand as the binder. Add the bentonite to the wet sand and mix throughly.

Mixing in the water with the sand first promotes adhesion of the bentonite to the sand grains.

Let the sand sit overnight after mixing to allow the moisture to distribute evenly thru the mix. Store it in closed plastic buckets or covered with plastic to keep in moisture.