Andrea Taurisano
il cimento
The procedure, in a Leica III, can be seen here (poor English, but easy to see what is doing): https://www.youtube.com/watch?v=KmmZgVwwx54&t=29s
Erik van Straten
Veteran
Thanks Andrea. The procedure shown, is with a IIIf (or IIIc). Opening a II, III or IIIa is much simpler. It is best to start with a II, difficult enough. However, it is good to see this video a couple of times before doing it yourself.
Erik.
Erik.