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MX developed sticky mirror

skydata
Posted 12/01/2019 - 19:53 Link
Hello all,

My trusty MX has not been used for some time and has developed a sticky mirror.

I bought it 2nd hand in 1986, already well-used with odd dents and brass showing but it has
served me well. It has been around the world with me, including 2 years in Fiji, where it was
kept in a plastic tub with a sealed lid and blue/pink indicating silica gel ,when I was at work.

I lost interest in photography on return to blighty in 1991 and it was unused (but still
in its plastic tub with silica gel, regularly 'dried' out back to blue) until retirement in 2008
when I noticed that there were black 'bits' on the mirror. This was the foam above the
mirror so Park Cameras serviced it (for about £70 I think). It was fine and I used it for
many more years occasionally but in 2009 I got a mint 2nd hand LX at LCE Guildford,
so it was relegated to the plastic tub+silica gel again.

I check it at least once a year to make sure the batts are ok but this time the mirror
sticks on the slower speeds. It is fine on 1/1000, 1/500, 1/250, sometime sticks up
on 1/125 and always from 1/60 down. Having stuck up, by moving the shutter speed
dial back to the 3 fastest speeds, it then works normally. Annoyingly, some time after
Park Cameras serviced it I noticed that the self timer no longer worked. I have to press
the little pin above the self timer lever to get it to time down. It was OK before.

The shutter blind seems to work fine. The slower speeds are definately accurate.

What could it be ?. The foam that park cameras' agent fitted is still ok.

Luckily the LX is fine, no sticky mirror symptoms at all, though getting to the age
where glasses are needed I might consider selling them (and the collection of
about a dozen A and M lenses) and just getting a compact camera. Since 2005 I
have taken more photos on my trusty Caplio GX8 TBH.
johnriley
Posted 13/01/2019 - 01:08 Link
The self timer is working as it should - the activation button is that tiny chrome button above the timer lever.

As for the shutter, a service might be needed to make it all run sweetly again.
Best regards, John
Kim C
Posted 13/01/2019 - 11:51 Link
Hi, I don't think it is "sticky mirror". That is purely an LX problem. If nothing else, it happens on all speeds. From your symptoms, it is more likely that the second curtain is not completing it's travel fully. A common fault on all the cloth focal plane cameras. Most likely due to the lubricant drying out. Some give the advice of increasing the tension on the second curtain but although it may "seem" to cure it, it doesn't really. Firstly it causes extra strain on the shutter which could cause long term damage and secondly it can make the faster speeds erratic.

A full service/CLA by Robin at Harrow Technical will sort it out.
danofmk
Posted 14/01/2019 - 07:35 Link
It's also some times a sign the batteries are on the go...
Kim C
Posted 14/01/2019 - 09:44 Link
danofmk wrote:
It's also some times a sign the batteries are on the go...

Not at all. The only things the batteries power on the MX is the meter. It is a totally manual camera and works perfectly well without batteries. Or at least it should do.
Edited by Kim C: 14/01/2019 - 09:45
danofmk
Posted 14/01/2019 - 14:35 Link


Monday mornings hey....

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