One-Piece Raised Roman Helmet Project

[Matt Lukes]

This tutorial seems to describe a process of raising shapes out of cold metal. Matt in the very first post mentions heated metal. Are both the approaches valid? Can you raise a helmet bowl without a forge?

I tried a little bit of cold forging and it's MUCH MUCH MUCH harder; to be honest, I just don't see it being particularly practical when hot forging is so much easier- especially given the amount of time and work already necessary to do it hot.

As for spinning, I haven't heard of any suggestion that iron helmets were ever spun- but then iron doesn't preserve terribly well so the somewhat subtle (compared to hammermarks) indications of spinning probably wouldn't be visible. Given that copper alloys can be softened and worked cold, whereas iron cannot be, I'm doubtful spinning would be likely though. It was probably already tough to do with copper alloys...