[johnnyrod]

No worries, think I am on the vinegar strokes. There is a small kink in one outer end of a shutter leaf which I think has been catching on things. I've done my best to minimise its effects by trying to straighten it, and moving it to the top of the pile. It's jammed a couple of times but is going pretty well since then. Need to adjust the timings and figure out how to collimate it without the stops or reference mark! I have an idea though.