Foam is all kinds of useful, but trying to cut it with scissors or a serrated plastic knife is usually an exercise in futility. What you really need is a hot wire for nice clean cuts. [Elite Worm ...

This may be a simple build, but it does produce a handy tool. [Darcy] demonstrates cutting foam with his creation in a video after the break. We think he could cut thin plastic with it as well ...

You can get a pack of foam grip tubing from Amazon for around $10. Just measure out a length of tubing the same length as ...