You could just let the foam cure at the tip and then shave it off with a utility knife, but there’s a better way.
Pro-style spray-foam guns allow you to dial in the size of the spray-foam bead, and you can reuse the can of foam again and again. The trouble is, you’re often going to end up with a big blob of foam on the tip of the gun, which can interfere with the nozzle. You could just let the foam cure and then shave it off with a utility knife, but there’s a better way. Anthony Nitopi of Sandy Hook, Conn., decided that the best way was to clean off the foam before it cured. He could’ve used acetone and a rag, but he didn’t want to drag those around the job site with him. He remembered that the principle ingredient of nail polish remover is acetone, and he recalled seeing his mom use a special jar of nail polish remover that has a foam insert that soaks up all the acetone. Just like a finger, you can slide the tip of the foam gun into the acetone-soaked foam insert and clean all the uncured foam from the tip of the gun.
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