CNC Foam Cutter Overview

A CNC Foam cutter is a machine that cuts blocks of foam into a variety of different shapes and sizes through the use of a computer that fully automates the process. This sometimes is referred to as a hot wire foam cutter because a hot wire is used to make the cut in a block of foam.

Usually the wire is made from stainless steel, nichrome and the wire can be very thick. The wire is heated using a process called electrical resistance which means it gets hot enough (around 200 degrees centigrade) to vaporize the foam before the wire makes contact with it. This process creates a smoother cut and produces a variety of shapes and sizes.

Depending on the length of the wire, the process will cut a shallow or deep cut. The wires have to be held in the machine under a very tight tension to keep the wire from sagging when making the cut. On many CNC foam cutting machines this wire is held vertically so that it doesn't create the problem with sagging.

These shapes are cut by the cutting wire that is attached to the machine. They will cut either polystyrene or polyurethane blocks. The types of foam that a CNC foam cutter can cut include anything that is thermofusible and expanded. What this basically means is that the foam has to be able to melt at one of the lower temperatures. Some of them include:

- Polystyrene -- these are blocks of balls that are expanded.
- Polystyrene -- this is extruded foam and comes in a variety of colors that include green, pink, purple or gray and these are usually plates that are smooth.
- Polymethacrylimide -- a very expensive material and it is rigid foam with a low density.
- Polypropylene -- which is flexible and expanded and can be a solution to protection from shock.
- Polyethylene -- these are foams that are tear resistant and flexible.

With the CNC Foam cutter you can form a more prism like or tapered shape in the block of foam. A hot-wire that is under a high tension to cut the foam. There are stepper motors that provide the precision and accuracy for the work and there are components called races that control the stiffness of tension of the wire.

Some CNC foam cutters also offer different attachments like a lathe and this allows the machine to use either preformed or stretched wire. Also the machine is able to cut a variety of shapes including spirals or blocks of ornamental structure like balusters for stairways or planters.

There are a variety of uses for foam cutters that include making signage, model airplanes, protyping, lost foam cutting and more. The CNC Foam cutter is a flexible machine and is only limited by the imagination.

Although many people prefer to purchase a CNC foam cutter there are also plans on the Internet that show how to make them inexpensively for hobbyists and others who are interested in working with foam.