I doubt a freezer would be cold enough. LN2 would easily do the trick - if I had some. Dry ice might be cold enough, perhaps, but that stuff's not cheap.

I put a couple on a metal rod a little while ago when I went home for lunch, and then took the propane torch to it. The plastic just melted off in minutes. I could probably do 100 or more solenoids an hour this way. When the plasitc was gone, there was left a nice roll of burnt copper on the rod. But is this burnt copper still #2?