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Asfarley
Tinkerer
Username: Asfarley
Post Number: 11
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, March 05, 2011 - 12:13 am: | 
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Hi, I've got a Yashica Electro Professional where the shutter opens while the film advance is wound, then closes when the shutter release is pressed. I've tried cleaning the shutter with naptha and dousing the entire shutter mechanism with natpha. The front and rear lens groups are removed. The shutter tends to work smoothly for a period (staying closed on wind) while it's wet with solvent but the problem reappears once dry. Does this sound like it needs lubrication? |
Neuberger
Tinkerer
Username: Neuberger
Post Number: 41
Registered: 01-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, March 05, 2011 - 03:04 am: |
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What you describe reveals there is still dirt to be removed, so keep on cleaning. Flusing the mechanism instead of cleaning the blades over and over with wetted cotton swabs is counterproductive.
Don't forget, haste makes waste. |
Asfarley
Tinkerer
Username: Asfarley
Post Number: 12
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, March 05, 2011 - 12:55 pm: |
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How could dirt on the blades cause them to open at the wrong time? |
Gez
Tinkerer
Username: Gez
Post Number: 265
Registered: 09-2007
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, March 05, 2011 - 01:16 pm: |
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Has the camera received the attentions of a 'repairer'? The problem you describe sounds as though the blades have been reassembled in the open position and not in the closed overlapping state. Just a guess.
The technique I use is to cock the shutter mechanism and assemble the blades clockwise with the their tips resting on a cork or similar support in the open space where the optics sit. |
Asfarley
Tinkerer
Username: Asfarley
Post Number: 13
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 06, 2011 - 03:35 am: |
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Gez: No repairers other than myself and I haven't fully disassembled the shutter. The camera was apparently working previous to the shutter/sticking issues. Also, if it was assembled incorrectly, would lighter fluid temporarily fix the problem? |
Gez
Tinkerer
Username: Gez
Post Number: 266
Registered: 09-2007
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 06, 2011 - 04:47 am: |
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That's baffling. Is the shutter unit a Copal SV or a Seiko ES? |
Asfarley
Tinkerer
Username: Asfarley
Post Number: 14
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 06, 2011 - 02:06 pm: |
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It says Copal Elec, not sure specifically what kind. |
Msiegel
Tinkerer
Username: Msiegel
Post Number: 222
Registered: 03-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, March 07, 2011 - 02:17 am: |
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Hi,
not sure if that is the same problem but have a look here at Dan Mitchell's repair site:
http://pheugo.com/cameras/index.php?page=copal
A bit down it says that a misplaced blade closing spring causes the blades to open on winding.
Remains the question why it works when wet. Maybe the spring is not displaced but the part it moves sticks or something.
No idea if that is really helpful, though.
Martin |
Josie
Tinkerer
Username: Josie
Post Number: 4
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, March 08, 2011 - 10:46 am: |
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The problem may be electrical. When the shutter is wound, a switch closes, turning on the metering & shutter control circuits. Once the shutter fires, this switch opens, shutting off these circuits.
Easy check - remove the battery. If the shutter acts normally and just snaps 1/500 of a second, the problem is electronic. If the shutter still acts weird with no battery, the problem is mechanical.
Good luck. |
Asfarley
Tinkerer
Username: Asfarley
Post Number: 15
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, March 08, 2011 - 03:02 pm: |
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Good idea Josie... this problem is happening with the battery out so I think it's mechanical. Also the correlation with lighter fluid indicates mechanical.
Martin - That sounds like a possibility, but I can't tell from his picture which he means by the shutter closing spring. Is it roughly in the center of the image? I just had a look at mine and I don't think it's exactly the same shutter, but it might be similar. There must be at least 8 springs in the shutter visible from the top but none of them look gunky or anything.
It's hard to tell which mechanism actuates/closes the shutter, otherwise I would just follow through the sequence. |
Asfarley
Tinkerer
Username: Asfarley
Post Number: 16
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 20, 2011 - 04:31 pm: |
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Hi, I'd just like to bump this as I have cleaned the shutter several more times, and it does not appear to be changing. Does anyone have general advice regarding what causes these opening-during-wind-on problems?
Thanks |
Ron_g
Tinkerer
Username: Ron_g
Post Number: 79
Registered: 07-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, June 21, 2011 - 04:29 am: |
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It sounds like the spring that engages the latch that holds the shutter cocked until you release it is faulty.I am not familiar with your camera or shutter but I have seen this problem occasionally on the Konica Autoreflex T* cameras that I have bought.Ron G |
Glenn
Tinkerer
Username: Glenn
Post Number: 934
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, June 21, 2011 - 06:19 am: |
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I am not familiar with this shutter, but the fault is obviously a faulty/misplaced latch or blade closing spring - as Ron and others have surmised. your flushing out the mechanism will have cleaned it well after the first application of solvent, the fact that the shutter functions properly when wet is to be expected and easily explained - surface tension, between the blades and the layer of solvent, is sufficient to make up the loss in mechanical resistance due to the faulty/misplaced spring. |
Nickon51
Tinkerer
Username: Nickon51
Post Number: 142
Registered: 05-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, June 21, 2011 - 07:44 am: |
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I think this model is the first of the Electro series and is similar or the same as the rest of the series like the Electro GS and GSN. If it is then the adjustments should be the same.
The shutter is a mechanical shutter which is mechanically tripped. The timing is controlled by the electronics. The electronics energise a shutter hold solenoid which holds the shutter open for the correct exposure time. There are a number of switches both in the shutter and at the end of the control rods that are pushed down by the shutter button. The electronics are switched on when the shutter button is pressed. When the film is advanced the control rods are reset to their resting position, ready for the next frame. It is very important that the mechanical parts of the shutter mechanism and the electronic switches are properly synchronised. If I had to guess at the problem with your camera, I would adjust control rods correctly.
The first step in this is to replace the return pad, or pad of death as it is commonly called. It is important that this pad is in good condition as it determines the rest position of the rods. Then adjust the control rods according to the manual. The larger rod is adjusted so that the release latch coincides with the shutter release. The other one is adjusted so that the transport release lever pushes the release out of engagement just before the shutter is released. It sounds like the transport release is not operating properly.
There is a service manual online somewhere, Google around for it or if you cannot find it I will send you the 5 pages that cover these adjustments.
Good luck
Greg |
