Exactly what speedracer said. Clean, smooth, fresh wood. Hitting it lightly with a compressor can't hurt either.. but the tack cloth just before covering in any case is your friend.
I covered this plane with Monokote in 2002. This picture was just taken about a month ago. The wood was exactly as has been described, with nothing on it. 16yrs and it's never given me any trouble... not even a sag. It's up to you if you want to experiment of course. I've got other planes that are older that are still very intact as well. Just sharing my experience here is all.
My thought is Monokote and films in general don't need a thing except patience to prep them, and practice applying them... and time to learn both. I don't think there's one "magic" cure to getting a good finish from a film covering. Good luck.
PS... I'd posted to this thread back in 2004 about which iron to recommend, and I still stand by that 21st Century iron too.. I've went through a few in those years.. but I won't use anything else.
