Source Contax II / III Shutter Ribbons?

True but there's always ebay for small amounts of specialised stuff. And at Christmas stuff gets given away on RFF...

Regards, David
 
Highway 61 said:
Given that what leaves wear on the ribbons fibers on every shot (and tears the ribbons out eventually) are the little sharp pins of the upper curtain (so that the upper curtain catches the lower one when both have finished their journey), using a thinner ribbon (at the cost of having to close the clutches a little bit, which is extremely easy to do and at no risk of damaging anything) is a valid option, because those darn upper curtain pins won't rub on the ribbon surface as much as if the ribbon was of the same thickness as the original.

This has been well documented in the past, especially by Zorkikat.

So, using the Aki Asahi ribbon remains the best of the best solution if you want 1/a shutter that will work very well 2/some ribbons durability over time.
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Resurrecting an old discussion. So how do people usually adjust the size of the clutches or buckles to achieve the desired clearance with the Aki Asahi ribbons? I have acquired some ribbons from him as all I have read suggests they are the best option but of course are thinner than original.

One possibility that occurred to me was to fabricate some small brass inserts from shim stock to correct the interference fit back to standard. In theory it seems a quick and easy way to get a good result, by calculating the difference in ribbon thickness and shimming it out. In practice it's probably not quite that simple. There would be a very slight change in the mass of the curtain. Whether to shim the top or bottom of the clutch (Highway 61's comments about ribbon abrasion being quite topical to this last point). Do people simply compress the clutches, mechanically, down to the required size for the thinner ribbons?

I've just bought a 50mm Sonnar to go with the camera that was acquired without a lens, so am hoping to get stuck into this work by the end of the year as, understandably, I'm excited about using a Contax.
Cheers,
Brett
 
I fitted Aki Asahi Ribbons twice to Contax ll cameras after advice from this forum and so far after a year or so mine are working fine. To close the sliding clutches simply apply sone pressure with your fingernail or very small nose jewellers piers and adjust to taste. The clutches on one of the cameras mentioned were worn down and needed to be closed irrespective of the thickness of ribbon to be used. It is a primitive system that seems to work.
Highway 61 has identified the wear problem as being the tiny hooks and my findings were the same as his, this seems to support the argument that thinner ribbon may last longer - also in this vein very light stitching is important, the ribbon is mainly held by it's loop around the small bar. It is immensely satisfying to finish this job and find that the shutter actually works!
 
Thanks for that information. I believe I have seen a suggested stitch pattern for fastening the ribbons on Rick's website, so I will follow that. I need to chase up a suitable thread for this purpose as I'd forgotten to get some, so thanks for the mentioning it.
Cheers,
Brett
 
Sarcophilus Harrisii said:
One possibility that occurred to me was to fabricate some small brass inserts from shim stock to correct the interference fit back to standard. In theory it seems a quick and easy way to get a good result, by calculating the difference in ribbon thickness and shimming it out. In practice it's probably not quite that simple.
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Funnily enough I've been thinking along exactly the same lines, but I haven't thought of a way that might work. I don't think it would be quick or easy!

I think the shim would have to go on the bridging part of the friction slot, and obviously it would have to be formed in such a way that it held itself firmly in place and its edges did not abraid the ribbon. Probably the only way it could be done accurately enough would be to make a pair of dies to stamp the shim to shape.

On balance, those who are modifying their friction slots to fit the ribbon available - narrower for Aki Asahi or wider for Kiev - probably have it right.
 
Grytpype said:
Funnily enough I've been thinking along exactly the same lines, but I haven't thought of a way that might work. I don't think it would be quick or easy!

I think the shim would have to go on the bridging part of the friction slot, and obviously it would have to be formed in such a way that it held itself firmly in place and its edges did not abraid the ribbon. Probably the only way it could be done accurately enough would be to make a pair of dies to stamp the shim to shape.

On balance, those who are modifying their friction slots to fit the ribbon available - narrower for Aki Asahi or wider for Kiev - probably have it right.
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I've not begun to pull down my II yet, as the ribbon only arrived recently (as indeed did the camera) and I'm awaiting the adhesive Aki recommends for gluing the ends. So my proposal to shim the slots is based on all the images and information I have found online. I do already have a range of brass shim stock here in different thicknesses, though. What I had envisaged possibly working was something like carefully measuring the length of the slot, cutting a shim slightly longer, and then pre-scribing it appropriately, either side of where it would protrude from each side of the slot, so as to induce it to fold cleanly around the ends of the slot (or clutch) in situ after it had been slid inside it. This would be followed by using tweezers and/or pliers to gently fold and wrap the shim around the top of the slot and crimping the ends shut on the outside of the slot, at the top. This way the ribbons would still slide inside a clean, unbroken surface of brass both top and bottom, that wouldn't abrade them.

As I suggested, calculate the difference in ribbon thickness, slide in the appropriate shim of brass, fold it shut, and Bob's your uncle. Sounds a bit too easy though, doesn't it? Which is why I'm also uncertain it's necessarily the best way to go, if it was I might have expected someone else to have already suggested it. Clearance around the top of the clutch being one point I'm unsure of (the shim would increase the inside and outside dimensions of the clutch, so would this then foul anything else?). I did wonder if anyone else had tried it, though, so it is nice to learn I am not the only person who's thought of it!
Cheers,
Brett
 
What have people elected to use as the thread for fastening the ribbons? It occurred to me today that perhaps non-absorbable nylon or silk medical sutures might be well suited to this role. I'm awaiting a copy of the Tooke book on the Contax shutter, and when this arrives, I would like to fit new ribbons during the holidays. All I need now is a suitable thread. TIA.
Cheers,
Brett
 
Sarcophilus Harrisii said:
What have people elected to use as the thread for fastening the ribbons? It occurred to me today that perhaps non-absorbable nylon or silk medical sutures might be well suited to this role. I'm awaiting a copy of the Tooke book on the Contax shutter, and when this arrives, I would like to fit new ribbons during the holidays. All I need now is a suitable thread. TIA.
Cheers,
Brett
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Hope to see some replies soon. Has anyone any experience with the 2.5 mm black ribbon from Micro Tools, Inc (Fargo Enterprises) in CA?
 
So far I've just used the ribbon sold by nobbysparrow on eBay. Seemed to be fine at least on two contax I's and Kievs I have. For the thread I've just used some green cotton thread we had at home, I also add some glue to hold the stitching together. The only problem I had was putting too many stitches in causing the curtains to jam when the shutter is cocked...so maybe thinner thread is a good idea.
Nathan
 
There was a thread that got deleted, in which a length of ribbons for Contax I was mentioned. IIRC it is supposed to be 10,5cm long. Can someone confirm it? I think it was Nathan that made that post.
 
Well, today I had to drop off a couple of things at my GP. I was going to ask him nicely if he could spare some non-absorbable sutures for me to use with my ribbons, but he had finished early for Xmas eve. So instead, I accompanied my wife on a visit to her favourite fabric and craft store. There we procured 100 metres of pure silk thread for $10 AUD. The ribbons Aki Asahi sent are black silk, so I went with white, purely to make it easier to see them during the process of tying them. I think this will be fine. If the factory considered silk to be the most durable and non-elastic material to use for the ribbons then I reckon it will do a satisfactory job of fastening them, too.
Cheers,
Brett
 
Replaced the ribbons in my II last night. It was a long night, tiny camera parts I can manage, but apparently I don't have the fingers and thumbs for ribbons and sewing. It got easier as I went though. Camera is running beautifully, 1/1250 slit width looks good and all the others fall into place. Quite a learning curve but I'd do another one. And considering how under valued the II is, (especially compared to other German rangefinders), I might, too.
Cheers
Brett
 
I use silk thread from the haberdashery to sew the ribbons on to the bars. Mine is red, very fetching against the black Aki-Asahi ribbon!
 
Henry Scherer has the correct ribbon but will not sell it. I wonder where he got it from?

Perhaps his supplier would sell to others.
 
Highway 61 said:
Unfortunately, they won't, because they're too thick for the Contax shutter.

Some years ago there were many good threads on this very forum which clearly explained which kind of silk ribbon had to be used in a Contax shutter, from whom to buy it (i.e., Aki Asahi), how to stitch it, and how to adjust the shutter curtains clutches to obtain the proper friction so that the shutter was accurate.

With many pictures and instructions. ;)

I have used some 3mm regular acetate ribbon (very likely to be the same as the one Grytpype sourced, albeit called "silk ribbon" by the seller) with no problem in several prewar Contax shutters, and, in case, have stocked some Aki Asahi genuine silk ribbon to fix my own camera after its next ribbons break-up.

overhaul79.jpg
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really neat how the whole thing can be brought down as one assembly like the Copal shutters :eek::eek::eek:
 
update: Asahi-san's ribbons work :eek::eek::eek:

there is a shop here selling ribbons that are nearly identical to the original ones but I dont know about the material but its certainly NOT silk.
 
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