Has anyone ever worked on them? My shutter currently works on all speeds, but T. Only the first stage of T works, so that the shutter is left stranded with the film exposed; it won't close again after the first stage. It seems like this could be fixed with just a slight increase in spring tension. My shutter curtains are in good shape, if it's not insanely difficult I would like to clean the mechanism. What's in like working on these shutters and how do you go about it?