Hot Wire Foam Factory 4" Hot Knife (Requires Variable-Heat Pro Power Supply)

After struggling with a dull blade for months, this knife glides through 4-inch foam like butter and the thumb-switch makes it easy to adjust on the fly. Just remember you need the separate power supply — but once you have it, the control is fantastic.

I was nervous about buying a hot knife that needs a separate power supply, but the precision on this 4-inch blade is incredible for detailed cuts. It heats up fast and the thumb-switch makes one-handed operation a breeze. Knocked out a complex foam project in half the usual time.

The thumb-switch is so convenient I can adjust heat mid-cut without setting the knife down, and the 4-inch blade carves through rigid foam like butter. I’ve been shaping floral arrangements with it all afternoon and the clean edges are exactly what I needed.