I've got several of these to do and am planning to tackle it in the same
way I used to tackle car bodywork in the 70s: grind out the rust, paint
with some sort of anti-rust primer, fill with polyester body filler,
sand, prime and top coat.
Is there anyone here who has renovated Crittall windows and has any
advice (other than replace them)?
....or any car body experts who can suggest primers, fillers and rust eaters?