How to Easily Cut Open-Cell Foam at Home

Do-It-Yourself projects are all the rage these days, as they’re a smart way to save a few dollars and add a personalized touch to your home. With its versatility and usability, foam is a material that lends itself well to the world of DIY, whether it’s being used for custom bed pad cushions to soften a rock-hard mattress, or for replacing a worn-out couch cushion.

As with any DIY project, the most important step is the preparation before work starts.  Projects involving foam make this step even more vital, and one of the most important aspects of foam work is knowing how to cut it. Open-cell foam, the soft and squishy type often used in foam mattresses and cushioning comfort products, is relatively light and fluffy. Because of this structure, it can be difficult to get clean cuts without knowing the proper techniques and tools to use. Additionally, different types of foam need to be handled differently when attempting cuts. For example, closed-cell neoprene will require a different cutting method and cutting tool than a couch cushion material.

There are two ways to cut memory foam and other similar open-cell foam varieties to achieve the best results, as well as one way to cut that may be tempting but is never recommended. People often think squeezing foam and compressing it to make it denser will give them quicker cutting. This is the last thing that should be done, as the foam responds fluidly to pressure as you cut, and when you release it, you will find you’re left with jagged, uneven edges.

As for the correct ways to cut foam, the easier of the two methods is using an electric knife, just like the ones for carving turkey. After carefully measuring and plotting your cushion shape on the foam, gently let the blade pass through the uncompressed cushion for easy, straight cuts, whether it’s for a couch cushion or a marine bed design. When using an electric knife, patience is key, as the cleanest cuts are a result of letting the knife slowly pass through the foam.

The other method is slightly more analog and requires manual cutting with a serrated blade. This may sound daunting to some, but is quite doable and can result in cushions as beautiful as those cut with an electric knife, as long as an individual takes his or her time. With a gentle sawing motion, start at the edge of the foam, again without compressing it, and slowly work the knife back and forth like you’re slicing bread. No matter how you’re cutting, it’s important to always work a stable surface that’s either protected from the cuts or a work bench you don’t mind scratching. Also, whenever possible, try to use a blade longer than the foam’s thickness to avoid cutting through the foam on both sides. A little preparation goes a long way on DIY projects, and knowing the best ways to cut foam is a great skill to have under your belt.