[MaSnaka]

Hey BE CAREFUL with that insulating foam in a can. That stuff can make a real mess and I don't believe it will come off the paint too willingly. There are also two types at home depot. One is low expanding foam and dries soft, the other is expanding foam and dries stiff. That expanding foam will cure into some very intereting shapes as it hardens. I would stay away from the expanding foam. Just be aware a little goes along way and there is no easy way to clean it up. I guess paint thinner and a rag might work.
Read the label on the can.
John