| Author |
Message |
    
Ron Mott
Tinkerer
Username: Pcar916
Post Number: 1
Registered: 08-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, August 03, 2006 - 12:18 pm: | 
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I have new F1 with a motor drive. The film advances up to approximately 13 frames (single frames, not motor-driven) with spacing in between each frame inconsistent with each shot. Sometimes there is up to roughly 1 inch between frames.
With the last shot the shutter and counter still work but it is a multiple exposure .
I need some advice to diagnose where my problem is. Today I will shoot two more rolls as follows:
1. Motor drive attached and manual advance between frames
2. Motor drive off the camera and manual advance between frames
I reckon that will tell me if I have a problem in the camera or the in the motor drive.
Is there anything else I can do to diagnose this further?
I can't locate a repair manual for this camera on the web anywhere so I'm flying blind about the diagnosis and repair sequence.
Thanks,
Ron |
Glenn Middleton
Tinkerer
Username: Glenn
Post Number: 14
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, August 03, 2006 - 08:40 pm: |
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Frame spacing is a function of the camera mechanism, the motor drive plays no part in this. Your test films will show similar faults.
Remove the emulsion from a cheap film. Load into camera and without closing camera back, advance and operate shutter a good few times. Apply pressure on the sprockets and take-up spool with finger and thumb whilst doing this, also mark position of the film gate's vertical edges for each frame.
You should be able to detect any slippage/damaged gears in wind mechanism by doing the above. You should also listen for the point when the shutter fully cocks and when wind-on locks.
You will have to examine the complete wind/cocking mechanism to pin-point the exact fault. |
Ron Mott
Tinkerer
Username: Pcar916
Post Number: 2
Registered: 08-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, August 04, 2006 - 10:23 am: |
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Hi Glenn, and thanks,
I used your finger-pressure technique and found that with light pressure on the sprockets and take-up spool the winder will operate and the film will move, but with slippage.
A little more pressure (not much) and the film will not advance at all. It's as if a clutch is slipping
With no pressure on the sprockets, or with almost none, the film moves more or less regularly at roughly 2-7/8 in per cycle (~48mm).
The wind-on and shutter both stop at the same time every time. But the wind-on doesn't lock at all. I can pull the film backwards with negligible effort.
Is there a clutch? What's next since I have no repair manual? Frankly, I'd like to tackle this myself as I'm fairly well equipped with tools. |
Glenn Middleton
Tinkerer
Username: Glenn
Post Number: 16
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, August 04, 2006 - 08:26 pm: |
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From your description I assume that with shutter cocked, you can rotate the sprocket shaft in either direction with your fingers. Have you checked that the rewind lever is fully released? A partially jammed rewind mechanism could account for your problems.
With shutter cocked engage the rewind lever, does the lever disengage freely when you partially press shutter release? If working the rewind lever a few times does not correct the problem, ie lock up the sprocket shaft, you will have to open up the camera and examine the wind mechanism. |
Ron Mott
Tinkerer
Username: Pcar916
Post Number: 3
Registered: 08-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, August 07, 2006 - 10:15 am: |
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The plastic sprocket rotates freely on the metal sprocket-shaft. However...
I notice that there are two opposing holes in the lower plastic boss that line up with holes in the sprocket-shaft.
There are no screws in my camera to fasten the sprocket (a sprocket-sleeve really) to the sprocket shaft. My A1 has a single screw that holds the two together.
Using a bright light and a magnifying glass I think I see threads in both opposing holes. As a test I tried using a bottom-plate screw in both holes.
The screw tries to start but binds so either the thread pitch is wrong or the screw is slightly too large... or both. I can't tell which and don't have small enough screw with that pitch in my parts bin.
Anyone got a New F1 parts body with those screws in it? |
