How to Carve Upholstery Foam

Prepare the cutting space by placing a wet paper towel or towel on the work surface. Place a mat, cutting board or block of wood on top of the paper towel or towel. This will reduce the amount of slippage from the cutting board while you work.

Measure and mark the cuts on the foam using a permanent marker. Use the marker to create indicators of special cuts as needed. The foam will be covered by the upholstery, so don't worry about making a mistake with the marker.

Try a bread knife. A bread knife is a serrated knife that is an inch or more wide and more than 6 inches long. Make sure that it is sharpened. Place the foam over the edge of the cutting surface. Use a sawing motion to carve the foam.

Use an electric knife if the bread knife doesn't work. The electric knife has a rapid sawing motion that should cut through the foam easily. Hold the knife at an angle to avoid carving a deep gash into your cutting board. Hang the foam over the edge of the cutting surface as needed to help guide the electric knife through the foam.

Buy an upholstery saw to get the job done faster and with more finished edges. Use the saw to round the edges. However, don't focus on smooth sides. The upholstery will be covered, so the smooth sides will never be seen.