I don't know if this helps, but...
I work in industry on optical equipment. One particular application needed a 35mm camera to record images. I say needed, past tense, as the requirement is now satisfied with digital image capture. But for about 12 years the job was done using Nikon F3s.
The equipment we are talking about is worth serious money, so the cost of a 35mm camera body, ANY body, was relatively negligible. The only requirement was reliability. Many cameras were tried before deciding on the F3 - and it proved bomb proof. Some cameras had dozens of films put through them every working day for years on end without any trouble. I know some people have said the earlier bodies are more reliable because of the lack of electronics - this strictly breaks the OPs 'Mechanical' requirement - but I simply can't remember ever having a fault on any of these Nikon F3 cameras. Occasionally the winders screwed up - but only after very large numbers of operations or a few times because some numpty tried to force a plug into the wrong socket and bent the gold pins...
In some ways they had an easy life. They had no batteries to leak (we used external power supplies), they were never moved or had lenses or finders fitted or removed - always sat stationary in the same temperature and humidity. Pictorial photographers' cameras have a much harder time of it, but even so, for reliability of continual operation I always found the F3 very impressive.
Last edited by steven_e007; 08-25-2011 at 07:47 AM. Click to view previous post history.