Thoughts on cutting foam

The marine environment is hard on upholstery. When asked to reupholster a seat, you find that not only is the outer cover in sad shape, but many times the wood back rotted. Reusing the foam is a 50/50 thing. If you are making a new plywood back and new vinyl upholstery it would be nice to use new foam.

What do you cut foam with? A foam saw! The most popular foam saw out there is the Bosch. This is a dedicated tool made to cut foam. It has a footplate that lets you make nice square cuts. If you remove the footplate you can freehand trim with it. One really nice feature is being able to hold the guide in your hand. You can easily follow cut lines on opposite sides of the foam blank. My personal experience with this design finds the tool slow cutting and does not leave the best finish. I have used three different units, one with brand new blades, and they all work the same. On top of that they are insanely expensive!



As hard as it maybe to believe, a turkey carving knife does a great job cutting foam. I purchased mine for 25 cents at a garage sale. It is lightweight, cuts fast and leaves a smooth finish. The only thing it is missing is a foot assembly. It is on my must have upholstery tool list.



At the upholstery shop where I work an industrial fabric cutting machine is used to cut foam. These are usually used to cut garment parts by stacking multiple layers of fabric and cutting the pattern. It is in some ways a much larger version the Bosch foam saw. It is much more stable and cuts reasonably fast. If you are cutting large pieces of foam you should look into one.


My favorite tool for cutting foam is the bandsaw. If you are cutting geometric shapes this is the tool! It is fast cutting and leaves a nice finish. If you need to cut an angle you just tilt the table. Using a fence, it is easy to cut parallel lines. Finally, this may be the best, you can glue foam to a plywood/plastic base and easily cut the foam leaving an overhang. Here is how you do it. Make a temporary fence out of wood the same or less then the thickness of your backing material. Cut a notch in it so the fence can extend past the blade. The base runs along the fence let’s say ¼”, for example, from the blade. The blade cuts the foam a perfect ¼” from the base material. I will post a picture to make it clearer.



It goes without saying that if you are freehand cutting thin foam just use a scissor. It would be great if others would share their experience.