[vicmortelmans]

Hi,

my MX has the typical shutter-related problems:

- uneven exposure in fast exposure times, because 2nd curtain catches up with 1st
- occasional sticky mirror (not caused by deteriorated foam, it's replaced already!)

At the repair service in Germany, I'm told that 95% sure the shutter assembly is defect, and repair is not feasible (availability of spareparts + high labour cost).

I can live with that analysis, but I don't want to give up like that... So I was wondering if I could perhaps temporarily leniate the problems by adjusting the shutter curtain tensions in some way (well probably: increasing tension on the 1st curtain). All of the curtains mechanics are hidden very deep in the camera and requires a complete disassembly, but by only removing the bottom plate, there's access to two screws which, I presume, are the tension screws for the curtains. Yet there's very little to find about how they should be operated.


The service manuals says: "Turn worm wheel two rounds to give the tension to both curtains." It doesn't tell which screw is 1st curtain and which 2nd (I suspect the first curtain to be the one most to the back) and it doesn't tell in which way to turn for increasing tension (I suspect turning right, but may be the other way around)

if only two rounds on the worm wheel is sufficient during reassembly, adjusting should be done very carefully!

Suppose there would be someone around on this forum that could reassure me before starting to fool around and share some experience, that would definitely improve my self-confidence in this matter

Best regards,
Vic

[Old Keith]

Vic, contact Robin Gowing and ask his advice. He is semi-retired now but does take on some work and he is magic with these old Pentax cameras. Best of luck

info@harrowtechnical.co.uk