CO2 Molding

To many of us, CO2 means Carbon Dioxide. Pretty hard to mold unless it is in very cold powder form. What does CO2 mean to you?

Always spell out acronyms the first time you use them in any document.

He is referring to Carbon Dioxide. It is used as a catalyst in the making of sodium silicate molds and cores in the foundry industry. Sand is mixed with about 4% by weight of sodium silicate and when activated by CO2 becomes hard. The mixed sand must be covered otherwise it will react with the CO2 in the air. There is ofter a crust that forms from this contact and it is removed and thrown away.

The mixed sand is rammed up in either a mold or corebox, an awl like tool is used to make holes to provide entry and the CO2 is injected throughout and the sand hardens. You can then remove the core or mold from the box and use as is or coat with a wash to improve surface finish depending on the metal being poured

Thanks for the clarification!

Isn't coke kind of expensive, not to mention illegal in most countries? After all, I doubt you mean coca-cola. Besides, it's downright hazardous. Anyone who inhales it by accident will get a high.

Rem is asking about CO2 moulding process being used in a foundry.