How To Cut Open-Cell Foam at Home

Do-It-Yourself projects are all the rage these days and a great way to save money, get involved and add a personalized touch to your home. Given its versatility and usability, foam is one material that lends itself well to the DIY world, whether it’s in the form of a custom bed pad to soften a rock hard mattress or replacing an old, worn-out couch cushion on a favorite piece of furniture.

As with any DIY project, the most important step is preparation. Foam is no different and knowing how to manipulate and physically cut the foam is vital. Open-cell foam, the soft, squishy variety used in foam mattresses and couch cushions, is a relatively light and fluffy material. Because of this, it can be difficult getting clean cuts without knowing how to do it properly and each variety of foam needs to be approached differently when cutting. A closed-cell gymnastic foam should be cut differently than a couch cushion material.

There are two different ways to cut memory foam and other open-cell foams to get best results, as well as one thing that should never be done when cutting that applies to both methods. Regardless of your cutting method, never compress the foam trying to get a quick cut. This will make jagged, uneven edges as a result of imbalanced pressure.

The easier of the two open-cell cutting methods is using an electric knife, like the ones used for carving turkey. After measuring and tracing your cut lines, these knives can make straight, even cuts incredibly easily if used properly. When using an electric knife, never force the blade through the foam. It will work its way through on its own, making much cleaner, straighter cuts.

The other method is using a serrated blade and cutting by hand. This is very doable and can result in beautiful cuts, but requires an individual to take his or her time and be patient. Using a gentle, back and forth sawing motion, start at the edge of the sheet of foam being cut and slowly work the knife back and forth like cutting a loaf of bread. For this method, as well as the electric knife method, it’s important to always cut on an appropriate surface and to use a blade longer than the foam is thick to ensure you don’t have to cut into the foam from both sides. A little preparation can go a long way with DIY projects and cutting a new foam product is no different.