In another post I was asking about folder 120 cameras and today I found one at the back of a cupboard, which I think someone gave me some years ago. It is a Royal made in Germany and the lens is a 1:3.5 /7.5cm Enna Werk Munchen Ennagon. The lens looks in surprisingly good condition, but cant see any evidence of an iris diaphragm opening and closing when I move the aperture lever. The coupled rangefinder seems to work and it has a lever wind which I think is also supposed to cock the shutter. However, the shutter does not work and also I cant seem to get the empty spool out the back. Any advice on repair please? Could I attempt this myself?