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Message |
    
Johnmiller2
Tinkerer
Username: Johnmiller2
Post Number: 1
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 17, 2012 - 10:07 am: | 
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Unfortunatley my trustworthy A1 is trustworthy no more!
Does anyone have any suggestions on how to fix a damaged winding sprocket on a Canon A-1? See below for the pictures. I found an OEM replacement sprocket, but have been unable to find any manuals on repairing these models. Anybody have any info/guides on a replacement like this?
Also - if this needed to be done professionally, how much do you think it could cost?
BTW - if anybody wants higher resolution pictures, please feel free to email me.
I appreciate your time in response.
Thanks,
John
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Thepurush
Tinkerer
Username: Thepurush
Post Number: 33
Registered: 01-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 17, 2012 - 11:03 am: |
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If the sprocket is the only problem then your cameara is stull usable. Fortunately all sprockets are same size with 8 pins and rotate just one full revolution each time film is advanced.
I I were you, I would replace it with another one from a parts camera. If at all the length may or may not match. Or I wd just cut off the bottom damahged portion fro this and glue a similarly cut piece from a good one.
In any case exact solution depends on the actual difference between the original and reaplacement part. But as I see it , its not so hard to restore camera. |
Johnmiller2
Tinkerer
Username: Johnmiller2
Post Number: 2
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 17, 2012 - 06:20 pm: |
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Thanks purush. Luckily I was able to snag an OEM replacement for this model, so hopefully it will be identical.
Any suggestions/walkthroughs on how to disassemble the camera so that I can make the swap?
Thanks again!
John |
Brcamera
Tinkerer
Username: Brcamera
Post Number: 169
Registered: 08-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 18, 2012 - 11:23 am: |
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John,
Replacing the sprocket on an A series Canon is not a trivial matter. The upper sprocket bearing must be removed and it is buried under quite a bit of mechanical parts. In fact, you would have to remove the mirror box and the shutter to reach the upper bearing. So having the correct sprocket is a start, but only a small part of the solution.
Also, contrary to what was earlier posted, all camera sprockets are not the same! True, they may all have 8 teeth, but that is where the similarity ends. Even sprockets from the same manufacturer may be different for various models in the camera line.
Bill |
Fiftyfifty
Tinkerer
Username: Fiftyfifty
Post Number: 54
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 19, 2012 - 01:06 am: |
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John
I have tried to this in the past, and my advice is forget it, just use the body for spares.
The film sprocket must be one of the first part but into the chassis when it was made.
Doug |
Rogerkuo
Tinkerer
Username: Rogerkuo
Post Number: 2
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, April 22, 2012 - 11:31 pm: |
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John,
My advice is the same : just forget it, because you should remove the winding lever, shutter button, ASA, eyepiece blinder, front cover units, top cover, unsolder the flex curcuit board, disconnet 3 mini connectors, about 15 wires, then take off the mirror box, loose the winding mechanism, you also need remove almost everything you see then replace this part. if you are not experienced on this, you may cause more problems than this sprocket broken. I have a canon A-1 service manual, if you need it , give me a email: [email protected] |
Rogerkuo
Tinkerer
Username: Rogerkuo
Post Number: 4
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 25, 2012 - 10:53 pm: |
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Hi John, i sent you several email but all of them failed. got feedack shown below. maybe the file size is too big.
do you have any other contact method?
Failed address: [email protected]
--- Session Transcript ---
Thu 2012-04-26 09:39:51: Parsing message <xxxxxxxxxxxxxxxxxxxxxxxx\pd35000060373.msg>
Thu 2012-04-26 09:39:51: * From: [email protected] Thu 2012-04-26 09:39:51: * To: [email protected] Thu 2012-04-26 09:39:51: * Subject: =?gb2312?B?tPC4tDogQ2Fub24gQS0xIFNlcnZpY2UgTWFudWFs?=
Thu 2012-04-26 09:39:51: * Size (bytes): 20161810 Thu 2012-04-26 09:39:51: * Message-ID: <[email protected]>
Thu 2012-04-26 09:39:51: Attempting SMTP connection to [dmu.edu] Thu 2012-04-26 09:39:51: Resolving MX records for [dmu.edu] (DNS Server: 218.2.135.1)...
Thu 2012-04-26 09:39:51: * P=020 S=000 D=dmu.edu TTL=(0) MX=[wilma.dmu.edu] {192.189.247.31} Thu 2012-04-26 09:39:51: * P=030 S=001 D=dmu.edu TTL=(0) MX=[elroy.student.dmu.edu] {192.189.247.26} Thu 2012-04-26 09:39:51: Attempting SMTP connection to [192.189.247.31:25] Thu 2012-04-26 09:39:51: Waiting for socket connection...
Thu 2012-04-26 09:39:51: * Connection established (218.94.78.178:4983 -> 192.189.247.31:25) Thu 2012-04-26 09:39:51: Waiting for protocol to start...
Thu 2012-04-26 09:39:55: <--> EHLO fullsharetech.com Thu 2012-04-26 09:39:55: <--> MAIL From:<[email protected]> SIZE=20161810 Thu 2012-04-26 09:40:00: <--> QUIT
--- End Transcript --- |
Johnmiller2
Tinkerer
Username: Johnmiller2
Post Number: 3
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 02, 2012 - 10:44 pm: |
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That's odd.
I appreciate the attempt. Would you mind sending it to this address? Gmail seems to be a better backup. [email protected]
Thanks again Roger, I really appreciate it. |
Johnmiller2
Tinkerer
Username: Johnmiller2
Post Number: 4
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 02, 2012 - 10:54 pm: |
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In a related but unrelated topic - since my primary A-1 is under repair, I went to my backup A-1 which now doesn't seem to be firing. Using a fresh battery, the problem is as follows:
The lever can advance (advancing screens and turning components), but the shutter won't fire when pressed. Also, I can continually advance the lever without a shutter release...which is most odd, since (even without a battery) my other A-1 would only let me cock the lever once prior to another shutter release. The LED's don't burn either in any setting.
So my question is: has anybody experienced this before? Is this an electrical issue since that's what controls the shutter, or is this mechanical? A combination of both?
Again, any help is much appreciated.
-John |
Fiftyfifty
Tinkerer
Username: Fiftyfifty
Post Number: 55
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, May 03, 2012 - 12:41 am: |
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John
When you wind on does the shutter blind move across.
If not then it is possible you have the double exposure lever problem.
If the shutter moves across and the shutter self trips allowing you to wind on again, then the problem is with the magnets in the base are not holding on.
Doug |
Johnmiller2
Tinkerer
Username: Johnmiller2
Post Number: 5
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, May 03, 2012 - 09:03 am: |
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Thanks fiftyfifty - I tried to troubleshoot under the pretext of a double lever problem, and I got it to fire again!
Hooray! I just loaded a roll and we'll see how she runs. Thanks again Fiftyfifty and rangefinderforum for being such a great DIY repair resource! |
