Many experienced metal casters will continue to use sand casting even though their abilities and resources allow them to use the other metal casting methods like Lost Wax Casting or Investment Casting. Sand casting involves less material and less effort than the other casting methods. Sand casting is a great way for new casters to get into the trade.



In sand casting, the metal caster will create a mold by placing an original in the flask which is filled with sand. The original will be a pattern of what you want to cast. By ramming or vibrating the sand, the caster creates a mold of the original. The casting sand used needs to be able to retain the shape of the mold. Finding the right mixture of sand to water is crucial. Too much water can ruin the mold and possibly destroy it while too little water will create a poor casting. Green sand is a type of casting sand that many prefer since its ability to retain the shape of the mold is far better then normal sand. Green sand usually contains bentonite clay, sand, and water.

After the sand is packed, the pattern or original is removed carefully. Molten metal is poured into the mold and allowed to cool. The metal caster will then break the mold and dig out the casting.

While sand casting has its benefits the use of green sand can greatly increase the likelihood of a successful casting. Green sand is not really green the color refers to the damp nature of the sand. Green sand is created by adding water and bentonite to the sand. One of the benefits of using bentonite in green sand is that it makes the sand more permeable which allows more gas to escape.

Metal casters can get the bentonite from a variety of sources like home improvement stores and even from household resources. Many have milled the type of cat litter that clumps since one of the ingredients is bentonite. Remember to work in a well ventilated room or to wear proper face gear when working with bentonite since it will irritate the lungs.

There are several recipes online for green sand but the most common method is experimentation. What you are looking for when mixing the sand, water, and bentonite is a texture that is not wet but damp and will retain its shape when molded.

The type of sand you use to make green sand depends on you and the availability of the sand. Many will use sand that they found out in the wilds of nature and some will buy bags of sand like playground sand. As you cast with green sand you will find out which works best with what metals.

Green sand is growing in popularity as more casters are recognizing the properties of this method. If you have traditionally used regular sand casting, green sand casting will prove to be easier to work with and will produce better casts.

The best part about green sand casting is that is does not cost a lot of green.