Nice! I've thought about a lathe with shaped wire -- but this is much simpler than the headstock and tailstock I imagined.

Wonder what thickness wire they are using for the cutter, and how many amps it takes? That's the real key to it.

The thicker the wire, the more amps are needed -- but you need a fairly thick wire to hold its shape. I wonder wht is being used here?

I've also got a foam lathe of a different type somewhere on my hard drive -- this one copies any profile shape, uses a dremel tool in a moveable base as a cutter, and the lathe part is turned by an old hand mixer.

The application was for making foam patterns for metal casting (I have a foundry I built -- so I found the info for this) but I don't see why it couldn't be used for planes.

Only problem is any cutter other than hot wire makes foam dust -- this one probably a lot -- but still, might be useful to somebody for something -- I'll post it when I find it.