Hmmm, kind of!
But........ It shows great potential as a hobbyist alternative, with some tweaking.
After a back and forth with @Andyhull on another thread it got me to thinking perhaps it's not as useless as my initial annoyance led me to think, (I broke a mainspring trying it but to be fair the spring had been previously abused and the tool wasn't ideally sized allowing the coils to jump and tangle).
I had a bit of a resize with sanding stick and scalpel and tried again and it's certainly got promise, I need to tweak the file to suit specific barrels but it's a simple quick 3 part print using barely any filament.
Obviously not anywhere near as good as the proper bergeon winder but definitely cheaper for the hobbyist, (even if you haven't already got a printer and had to buy one first).
Here's a video of it if anyone is interested, comments and ideas are welcome.
I have a Rotary Monza I am fixing up. I disassembled the barrel and removed and cleaned the mainspring. I secured a copy of the parts list and it shows that as well as the mainspring, there is also a Brake Spring (part 775 on the picture). What is it, and do I really need it? Certainly Cousins does not sell it. I googled AS 1902 brake spring and ONE result came up of a Russian watch forum discussing this item. Apparently it is thicker than a normal spring and it seems to have some sort of bent over feature on it. Can I just make one using the old mainspring? If so, how long should it be? Is it really necessary?
ROTARY Monza AS 1902.pdf