I have a completely hand forged one, and have made and used a number of them from the stamped sheet-iron skillets you can currently buy. They are nice, and pack well. You do have to watch your heat more with the thin sheet iron compared to cast iron. Don't do what a bunch of the Civil War boys have been doing to theirs to clean them. They turn them upside down over the fire to "burn" the grease out of them before putting them in their packs. This will warp and wear them out reall fast. Just wipe them out and wrap them in something you don't mind getting a little grease on.
But there are problems with folding handle frypans. I and a lot of other people have not been able to find any documentation for them. The only known original one that everyone points to is in Madison Grant's Hunting Pouch book - and it is listed as a Rev War "folding mess kit", NOT a frypan. And it's provinance has been questioned. A whole lot of people REALLY WANT TO find documentation for folding handle frypans. THEY REALLY REALLY WANT TO! But, nobody has, yet.
So, personally, I don't carry mine much anymore. Only to the occasional "buckskinner" type event where authenticity doesn't matter much. It falls into that other category: if they would have had it, they would have used it. It's a neat idea, and handy, but doesn't appear to have existed back then.
If I carry along a frypan now, it's one with a LONG fixed handle as seen in numerous voyageur paintings. Or a Spider - a frypan with three long legs riveted on, and a long handle. Examples can be seen in many paintings, and in books like Collectors Illustrated Encyclopedia of the American Revolution, Early American Country Furnishings, and Where Two Worlds Meet.
So goes this Living History journey. I miss my folding handle frypan. I await further research!
yhs
Mike Ameling