KIEV-4A cocking problem after shutter ribbon replacement.

[ForestCap]

Hi, the shutter ribbons of my backup KIEV-4a broke after like 50 times of dry firing. So I replaced the ribbons with the help of KIEV survival site and rick_oleson.

The replacement went slow but well, however I did mess up something during the replacement work: now the curtains don't go up to where they should be when cocking,


This is how the curtains look like when cocked at 1/50s
1/50S by , 於 Flickr

And at 1/250s
1/250S by , 於 Flickr

1/500s
1/500S by , 於 Flickr

Does anyone know, what did I mess up and how to fix this problem?
Thanks in advance!

 

[nhchen]

It looks to me that the gears on the curtain rollers have gone out of sync.

To fix that you'll have to take the whole shutter out of the camera, remove the top curtain roller and re-sync them. It will be quite difficult the first time you do it though. If I remember correctly, in the end you want the top curtain to stop at 1-1.5 slats above the bottom curtain after the shutter is cocked on the fastest speed.

I followed the instructions in the mazenberg camera manual available online somewhere.
Regards, Nathan

 

[ForestCap]

Hi Nathan, thank you for your informative reply! I found the manual and compared my camera with an illustration showing how the top roller and nearby cogs should look like, and it turned out to be you are right, my upper roller and the cogs are way out of sync. So it's time to take out the shutter unit as a whole and reinstall the roller.
Thanks again.

 

[Valkir1987]

How far did you disassemble the camera to replace the ribbons?

 

[ForestCap]

How far did you disassemble the camera to replace the ribbons?

As little as I could: I only removed the film aperture opening plate (or Film Plane Casting by KSS) to expose the shutter ribbons.

Thinking back, the only outrageous thing I did during the ribbon replacement is that I cocked the shutter when there was no tension and no ribbons. This might be what caused the roller sync problem. But still, I can't figure out at which point the roller and the gears went through an irreversible action and got out of sync.

 

[Valkir1987]

As little as I could: I only removed the film aperture opening plate (or Film Plane Casting by KSS) to expose the shutter ribbons.

In that case, the upper curtain must have flipped around its roller before refitting new ribbons. There is no misalignment of the gears.

You have to fit new ribbons (the old ones can not be re-fitted) and wrap the curtain around its roller again.

What kind of ribbons did you use?

 

[rick oleson]

As above ---- remove the ribbons and you should be able to get the rollers back in synch, and then install new ribbons again.

 

[ForestCap]

As above ---- remove the ribbons and you should be able to get the rollers back in synch, and then install new ribbons again.

In that case, the upper curtain must have flipped around its roller before refitting new ribbons. There is no misalignment of the gears.

You have to fit new ribbons (the old ones can not be re-fitted) and wrap the curtain around its roller again.

What kind of ribbons did you use?

Thanks for your replies! Right, the roller must have been flipped.

I bought the ribbon from here:
http://www.ebay.com/itm/Strapping-f...pe-contax-1m-Ribbon-for-shutter-/181758866553

 

[Valkir1987]

I bought the ribbon from here:
http://www.ebay.com/itm/Strapping-fo...-/181758866553

I have that ribbon too, and sorry to tell you its not the right ribbon. The ribbon being sold as the original is made for the Kiev 88 which uses thicker ribbon. It is simply too thick to work properly in a Kiev 4.

Berisfords double sided satin ribbon 3mm width is the best substitute which I had so far. Thickness should be around 0.35mm.

Some have suggested to use the Aki Asahi ribbon intended for use on the prewar Contax. The tape guides need to be pinched. However, this is a irriversable proces and I do not recommend it in any way. Getting the right parts without having to modify your camera is the proper solution.

 

[ForestCap]

It has been some time since I started this. Life got in the way but I finally finished the work.

The ribbon I bought from eBay works well on the camera I am working on (1963). I used a film tested KIEV-4A (1969) to compare the ribbon friction (catch the lower curtain when releasing at B, and slide it up and down with hand to feel the friction), and the frictions of the ribbon on the two cameras are more or less the same.

At 8 turns of shutter tensioning and the camera is working fine.

PS: I put the top cover from a 1980 KIEV-4a on it because the round-shape eyepiece makes it slightly easier to see the whole frame.