Foams Advantages

Sheets of form are readily available in extruded and expanded forms (see below for definitions). Both types are available in 3/4" to 3" thickness from local building supply yards. The large blocks that are used to cut longer shapes are also available in most cities. If you are not familiar where to purchase these blocks, check our Links Page or call us and we will supply you with this information.

Foam is very inexpensive. When cutting the foam on a SCULPTOR HD foamcutter, the cut shapes have a very high profit margin.

Foam is suitable for use indoors or outdoors.

Foam can be coated with many different products to achieve any desired finish. 

Foam will last virtually forever if it is kept coated.

Technical Information

The most common types of foam which are suitable for cutting on a hotwire foamcutter are expanded polystyrene and extruded polystyrene.
 

Expanded Polystyrene Foam

Expanded polystyrene foam is used for coffee cups, coolers, insulation, packaging products for shipping, etc. It is made up of about 2% polystyrene and 98% air. It is manufactured by heating styrene pellets with steam so they expand rapidly within a mold and form a large block of low density foam. The expanded beads remain as air filled closed cells that resist the conduction of heat, and therefore are efficient insulators. This foam is light, usually 1 to 2 pounds per cubic foot, and very inexpensive. No CFC's are used in creating the foam. It doesn't degrade under normal circumstances because EPS is inert and has a very stable molecule. Foam is increasingly being recycled, to the benefit of the environment.

Extruded Polystyrene Foam

Extruded polystyrene foam is the same chemical product as the expanded foam, but it is manufactured using a different process which extrudes the foam, resulting in a denser, more homogenous product with much smaller air pockets. It is commonly found in sheets of 2 pound per cubic foot density or higher, and is usually colored blue, green, gray or another color. Styrofoam™ is a registered trademark of Dow chemical and is a blue extruded sheet readily available almost anywhere. This type of foam is excellent for making signs and other display products. 

Coatings

Both types of foam are easily coated with water-based paints like vinyl acrylics, and the paint is absorbed slightly into the surface of the foam by capillary action, thereby giving it a harder surface. Cement based coatings are also common, especially in the architectural field, and polyurea coatings are used for their hard, smooth finish. There are also the metal coatings from Plate-All and LuminOre.

For detailed information on the types of coatings available, please see the Coatings page for a list of manufacturers of coatings, adhesives, and other foam related products. On their websites you can find a great deal of information on this topic. You can also call us and we will be happy to help.