How Do Compression Cutters Work?

Have you ever wondered how some of your most comfortable pieces of furniture came to be? Cutting and trimming some things like a foam mattress or chair cushion that has straight lines and 90 degree angles would seem to be pretty basic. But what about that memory foam pillow or the cushioning foam pad that hugs your hips at night? Or the custom foam packing materials you ordered for your company’s new product? Surely their smooth, clean curves would be next-to-impossible to cut by hand and still be sold at a reasonable price. So what’s the secret to these pieces of foam? In many cases, these special foam forms are created using compression cutting technology.


The process of making contoured foam involves molds that affect foam’s pressure dispersion when under compression. Templates for these shapes are produced on a CNC router, most often from wood, which reflects the ultimate appearance of a product. Foam is placed over these templates, compressed, and passed through the machine as a blade passes through the foam, directly above the mold. This compression cut results in two interlocking forms; the section that was forced inside of the template during compression, and the piece skimmed off the top above the blade. Raised areas in a template create greater compression, which means more foam gets squeezed into that area. When released, this makes a high point on the actual foam form. This method is often used to create snugly fitting packing foam and zoned mattresses for foam bedding.


These computer-created, foam-forming templates are able to be made in nearly any pattern or design, featuring contours, curves and tapers. The only thing that keeps this process from forming full 360 degree moldings is the flat side that forms from the cutting of the blade.