Asahi Pentax LX 'Sticky Mirror Syndrome'


Peter Elgar

Link Posted 03/07/2020 - 17:10
hi All --- I have two Asahi Pentax LX one bought 1987 the other s free gift from Pentax House ( RE -- the Famous FIRE Story) BOTH have then infamous 'Sticky Mirror Syndrome and both had exposure troubles!
I have cured the Exposure Troubles by Rotating the Exposure Compensation and ASA dials back and forth as on the ME Super, to clean the contacts underneath and both agree with my Weston Master V and on film gave good exposures now BUT the 'Sticky Mirror' drives me Nuts ! I had a look -- there are two very small 'Mirror Rests' , slightly different from 1987 model to the later model -- could i put a very small amount of Iso-Propyl Rubbing Alcohol OR Lighter Fuel ( Butane) on them to see if it cleans off any 'sticky' surface ?
been a member of Pentax Club since the Ron Spillman era! Got COMPUTERISED at last - DIGITISED? Taken the PLUNGE - BUT FILM STILL RULES !!!

Benz3ne

Link Posted 03/07/2020 - 17:50
Id say yes, but be judicious in your application. Use a cotton bud and remove most of the bud, so theres little cotton. When you apply the isopropanol (Id say itd work better initially at removing gummy bits), Dan lightly on a paper towel before working lightly.
Might leave a chalky/powdery residue after full cleaning so wipe down, again carefully, with naphtha and you should have a clean mirror again!

johnriley

Link Posted 03/07/2020 - 23:55
Mirrors should never be touched to clean them, the front surface silvering is fragile. But Peter wasn't referring to stickiuness on the mirror surface, but stickiness in the flipping action of the mirror mechanism. I think an overhaul would be the surest way forwards.
Best regards, John

Helpful

pschlute

Link Posted 04/07/2020 - 04:16
I think all LX cameras suffer from this. Mine certainly does. I tried a little talcum powder on mine and it improved things for a while. I dont think alcohol will help* and may make things worse. The rubber pads have decayed and some solvents may eat into it.

Another solution I have not tried is to file a pencil lead until you have a small amount of powder then apply this to the pads.

* Well alcohol may help....you can have a little drink after you have pressed the shutter and are waiting for the mirror to lift !
Peter



My Flickr page
Last Edited by pschlute on 04/07/2020 - 04:18

Helpful

Peter Elgar

Link Posted 04/07/2020 - 09:45
John Riley is right -- it's not the mirror SURFACE or the Foam Mirror Bumper which is still good on both LX cameras -- it takes about 4 seconds from pressing shutter release to mirror finally moving up and shutter firing! WIFE has forbidden me to 'Spend Money on my Old Cameras' so I wanted a DIY solution if possible. I was given a great MINT Chinon CG-5 Pentax 'K' fit which has NONE of the Pentax ME Super and LX exposure problems where you have to rotate the Exposure Compensation and ASA Dials back and forth to clean contacts underneath and NO Sticky Mirror trouble so LX 's may be 'Retired' !
been a member of Pentax Club since the Ron Spillman era! Got COMPUTERISED at last - DIGITISED? Taken the PLUNGE - BUT FILM STILL RULES !!!

Benz3ne

Link Posted 04/07/2020 - 10:17
My apologies for the misunderstanding!
Hopefully you find a suitable fix. That Chinon sounds like a great option for someone looking for a film camera.

Peter Elgar

Link Posted 06/07/2020 - 13:31
YES -- here it is with the 'Sirius' Zoom it c ame with but the Sirius has FUNGUS inside. The CHINON 50mm f1.9 is SHARP at full aperture and I took it Berlin in 2017 and got great Colour Pics.

Chinon CG-5 by Peter Elgar, on Flickr
been a member of Pentax Club since the Ron Spillman era! Got COMPUTERISED at last - DIGITISED? Taken the PLUNGE - BUT FILM STILL RULES !!!

Benz3ne

Link Posted 06/07/2020 - 15:14
Peter Elgar wrote:
YES -- here it is with the 'Sirius' Zoom it c ame with but the Sirius has FUNGUS inside. The CHINON 50mm f1.9 is SHARP at full aperture and I took it Berlin in 2017 and got great Colour Pics.

Chinon CG-5 by Peter Elgar, on Flickr

Looks very clean! I think I might keep an eye out for one myself.

Also, apologies for derailing the thread. I hope you find a suitable, inexpensive fix soon.

Peter Elgar

Link Posted 06/07/2020 - 16:40
It was from a Widower -- he had a Ugandan Wife who died and whose camera it was hardly ever used, then my Filipina Wife fixed him up with a Filipina Wife then HE Died ! His Prostate Cancer was worse than mine and spread ---
been a member of Pentax Club since the Ron Spillman era! Got COMPUTERISED at last - DIGITISED? Taken the PLUNGE - BUT FILM STILL RULES !!!

johnha

Link Posted 07/07/2020 - 01:35
Both my LXs suffered from sticky mirrors, I had Robin at Harrow Technical repair them (well worth it). Before the repairs, I found cycling the mirror lockup up and down immediately before shooting would often help - at the risk of more damage.
PPG Flickr

Helpful

Peter Elgar

Link Posted 11/07/2020 - 11:40
johnha -- I 'Recycled the Mirror up and down' and fired the shutter on my 1987 LX then it jammed -- the focal plane shutter has now stuck halfway across and there is a fault in the 'Capping' of the blinds so that 1987 one is now 'Nackered' !
been a member of Pentax Club since the Ron Spillman era! Got COMPUTERISED at last - DIGITISED? Taken the PLUNGE - BUT FILM STILL RULES !!!
Add a Comment
You must be registered or logged-in to comment.