Casting sand / moulding sand 25 kg

Casting sand, also known as moulding sand, Brussels earth or greasy earth, is an oil-bonded mineral mixture. You use it to make moulds for sand casting. With this technique, the original object stays intact. The sand withstands temperatures up to about 900 °C.

How sand casting works

The process step by step:

1. Make a negative impression of every side of the object
2. Release all parts from the object
3. Reassemble the mould parts and fasten them together
4. You now have a hollow mould for molten metal
5. Let everything cool down before removing the blackened sand

Any leftover sand can go back into the bag. This technique only works with objects that release from the mould.

Reuse and composition

You can use moulding sand several times, as long as the binder still works. The composition determines whether a project succeeds. Things can go wrong in three ways: mixing with talcum powder, thermal stress that causes the oil to separate, and ageing of the product. That last one takes many years.

Sand that has become mixed with talcum powder is best not reused, and should not be mixed with fresh greasy earth either.

Applications

In most cases, bronze and aluminium are the metals of choice. Keep an eye on the 900 °C upper limit. The sand is especially suited to smaller and simple shapes, such as medals or coins.

Making your own moulding sand

We don't recommend it, because the right composition is decisive for the result. Also bear in mind that the object to be cast must be able to release from the mould and must not be made of a moisture-retaining material. For a wax or damp clay model, casting sand is not the answer.

Time estimate

• Two production moulds: 3 hours on average
• Casting and cooling: 1 hour on average
• Finishing: depends on your own preferences

Specifications

• Type: oil-bonded mineral mixture
• Maximum temperature: approx. 900 °C
• Weight: 25 kg
• Suitable for: bronze and aluminium, smaller and simple shapes
• Reuse: possible as long as the binder works