FED2 shutter curtain bounce

[simaken]

[FONT=Verdana,Arial,Helvetica]Hello.
I am repairing junk russian FED2 early model.
I diassembled almost all and replaced curtains.
But because of closing shutter bounce, I set shutter tension to be very weak.
(about 1 turn from no tension.)
Is it correct?
[/FONT][FONT=Verdana,Arial,Helvetica]That is observed by oscilloscope and photo-transistor on end edge of frame. [/FONT][FONT=Verdana,Arial,Helvetica]
I greased to tension spring with new grease that is softer than original.
Does it effect?
Is there a solution for shutter bounce?[/FONT]

 

[wolves3012]

If the shutter works correctly, I wouldn't worry over the actual number of turns. Having said that, a single turn sounds too low, I'd expect at least a couple to be needed. It's surprising how little tension is needed though, on a smoothly-running and freshly CLA-ed camera.

As for shutter bounce, there is no curtain brake on the FED 2, as far I can recall. In which case, not much to be done about bounce.

 

[Steve M.]

For what it's worth, many years ago I bought a Fed 2 from someone on this forum that had been CLA'd (the only working Fed 2 I've ever owned by the way). The shutter tension had been set so lightly that I was sure the photos would be underexposed, but they were perfect.

 

[simaken]

Thank you for your reply. As you say,　FED2 has no shutter brake. Differences before and after repairing are lubrication and thickness of curtain and material of curtain. I guess sticky grease of tension spring may act like friction dumper. But the grease may be simply degraded. Thickness of curtain cloth I use is t0.2mm . Original may be thicker (original is too degraded and painted, so can't scale its thickness.) If thickness was thicker than new one, travel length of curtain might be longer, and edge of curtain might deeply hided from picture frame. So bounce might be hided. When I have opportunity to see other fed2, I will observe shutter position.

 

[simaken]

Pictures of curtain position

https://box.yahoo.co.jp/guest/viewe...1-c081-4b53-b7c6-e43e9cea430d&viewtype=detail

https://box.yahoo.co.jp/guest/viewe...c-91f2-4a40-af76-5dc6f56ee2b8&viewtype=detail

 

[Valkir1987]

The shutter brake only slow's down the first curtain. I have a Fed 3 on my desk which had the shutter bounce problem too. If you release the curtain's position towards the end of the gate, with 1 teeth of the drums gear. The problem should be solved. (if the curtains are glued and aligned properly, and are properly tensioned)

 

[simaken]

Thank you for replying Valker1987. Edge of the first curtain is very close to the edge of picture frame. (please see second picture) On my fed2, restriction pin and groove are under shutter drum not on idler gear. So before glueing, I tried tacking with double sided tape several times for alignment. I think travel length of first curtain must be longer than present curtain.(though curtain I made is same length of previous one.) I think that it need to thicken the curtain drum with paper or something, or use longer curtain. I will try it next time.

 

[Ron (Netherlands)]

Thank you for replying Valker1987. Edge of the first curtain is very close to the edge of picture frame. (please see second picture) On my fed2, restriction pin and groove are under shutter drum not on idler gear. So before glueing, I tried tacking with double sided tape several times for alignment. I think travel length of first curtain must be longer than present curtain.(though curtain I made is same length of previous one.) I think that it need to thicken the curtain drum with paper or something, or use longer curtain. I will try it next time.

Looking at your second picture the shutterdrum indeed like Valker1987 said, needs a little correction. Please also watch the position of the second curtain lever; see below picture. If the shutter drum isn't in the right position, the second curtain lever will be out of position too and therefore causing incorrect shuttertimes. In unwind position the second curtain lever should be in position as in the below picture. If not then you'll need to change the position of the drum, until the lever is in the correct position.

 

[simaken]

Thank you very much Ron for advice and taking picture of your camera for me. I took picture of my fed2. I think the lever position is roughly correct position. But the clearance between the lever and stopper is wide. If I bend the lever or solder a little piece of metal to the lever, I think the curtain position will be better. I drew a sketch of relation of lever and curtain. It is my understanding of your advice.

https://box.yahoo.co.jp/guest/viewe...a-72f7-4abc-b98d-e6c820f2e55c&viewtype=detail

https://box.yahoo.co.jp/guest/viewe...6-f265-4a08-949f-b7539ff37398&viewtype=detail

https://box.yahoo.co.jp/guest/viewe...f-c943-48fc-8171-46cbf336508f&viewtype=detail

 

[Ron (Netherlands)]

Thank you very much Ron for advice and taking picture of your camera for me. I took picture of my fed2. I think the lever position is roughly correct position. But the clearance between the lever and stopper is wide. If I bend the lever or solder a little piece of metal to the lever, I think the curtain position will be better. I drew a sketch of relation of lever and curtain. It is my understanding of your advice.

https://box.yahoo.co.jp/guest/viewe...a-72f7-4abc-b98d-e6c820f2e55c&viewtype=detail

https://box.yahoo.co.jp/guest/viewe...6-f265-4a08-949f-b7539ff37398&viewtype=detail

https://box.yahoo.co.jp/guest/viewe...f-c943-48fc-8171-46cbf336508f&viewtype=detail

I couldn't open your pdf on your site. From the photo's, especially the first one, I would say that the curtain lever is still out of position a little: in wind position (re your first photo) the lever should be more in the middle of the notch of the second curtain latch; yours is more to the right as almost resting against the latch.

 

[simaken]

Thank you for Reply Ron. I converted PDF to jpg hard copy in the link below.
I understand the position of the lever of my FED2 is too right compared from proper position. Thanks to all of you, I can get clue of solution.

https://box.yahoo.co.jp/guest/viewe...f-d856-496c-bc66-87f94f0a4a6b&viewtype=detail

 

[Ron (Netherlands)]

Thank you for Reply Ron. I converted PDF to jpg hard copy in the link below.
I understand the position of the lever of my FED2 is too right compared from proper position. Thanks to all of you, I can get clue of solution.

https://box.yahoo.co.jp/guest/viewe...f-d856-496c-bc66-87f94f0a4a6b&viewtype=detail

Indeed I could see now your schematic. Yes this is all there is to it. If the position of the second curtain lever is OK then you also know that the position of the curtain drum is OK. However if at that point the curtains don't close as they should - in unwind position or during winding - the position of the curtains or the curtain ribbons is wrong and should be adjusted.