Mr_Flibble
In Tabulas Argenteas Refero
Well, no reason left not take it apart now 😉
Contax I ribbons
- Thread starter Dralowid
- Start date
- Latest activity Latest activity:
- Replies 714
- Views 85K
Pioneer
Veteran
If you know a good machinist it may be possible to recreate these springs from new music wire of the correct size. Either that or you may find something on McMaster Carr's website.
It is certainly worth a try. Since it is more likely that these springs are the parts that will break or wear down on this part, new ones could return the entire drum to the same condition as the newly manufactured ones.
It is certainly worth a try. Since it is more likely that these springs are the parts that will break or wear down on this part, new ones could return the entire drum to the same condition as the newly manufactured ones.
Livesteamer
Well-known
I have been following this thread with interest and admiration for the skill and patience you folks have displayed. Pioneer is on the right track. New springs need to be found and I would suggest buying commercially made springs. I'm a retired machinist, I've made springs in the past and it is just as much art as science. There should be a great variety of commercially made springs available and finding some and fitting them might be the answer. Good Luck. Joe
Jerevan
Recycled User
Perhaps these fellows can help with restoring/making/finding new ones if you are in Europe:
https://www.federnshop.com/de/
https://www.federnshop.com/de/
Highway 61
Revisited
Now that I've looked at the pictures of the previous page, the Contax I drum unit looks like the same as the Contax II drum unit.
Are they really identical ?
If yes, that would be excellent.
Here are some sketches and instructions by Rick Oleson about how it works :
Are they really identical ?
If yes, that would be excellent.
Here are some sketches and instructions by Rick Oleson about how it works :
Highway 61
Revisited
I will add that most of those prewar Contax spring units are now broken because repairmen decided to fix reluctant shutters by overtensioning the bottom drum unit over the years and decades instead of taking the whole shutter apart and carefully cleaning the grime off the shafts and gears.
Deklari
Well-known
Deklari
Well-known
this is a difference
Deklari
Well-known
And there is no way to flip them. They are not symmetrical.
Highway 61
Revisited
The trick would be to shorten then re-machine the right end of the central axle of a good Kiev drum unit to install it in a Contax I shutter unit, if possible.
Not too sure, though. Re-machining the axle end so that it can have a slot for the tensioning step would be easy, but what about the position of the ribbons spools on this drum unit once installed in a a Contax I ?
Not too sure, though. Re-machining the axle end so that it can have a slot for the tensioning step would be easy, but what about the position of the ribbons spools on this drum unit once installed in a a Contax I ?
Erik van Straten
Veteran
Maybe the spool ends of a Contax I will fit to an axis of a Kiev, but this all remains guesswork. We need a good instrument maker.
I wish I had the time to experiment now I see all this new information, but I will be very busy with work until January.
Maybe the axis of a Kiev can simply be turned (left to right) and the left and right springs switched.
Erik.
Deklari
Well-known
No problem for left site, it is possible to make slot for the tension there... problem will be with existing right slot, no room for cut there.
Deklari
Well-known
Ok, I moving forward
I trying re-pair old spring ..
I have put spring on cylinder.. and heat (on gas stove) for 20-30 seconds...
I trying re-pair old spring ..
I have put spring on cylinder.. and heat (on gas stove) for 20-30 seconds...
Dralowid
Michael
The manufacture of custom springs is no great problem, apart from significant cost. There a specialists in the UK who could do it but machine 'set up' costs would be high. I doubt the cost would drop much with any volume that might be achievable.
The problems I see are:
1) We do not have a good spring to copy. The thing is an awkward double spiral that turns back on itself
2) The chances of deforming the springs during installation are high. OK so my dexterity is nothing like Deklari's but I fear we would mess up a few before we had an acceptable result. The anchorage to the shaft is also very fiddly.
It is interesting that neither Deklari's nor my spring are actually broken. As far as I can tell it looks as if the outer coil or spiral which is unsupported has collapsed towards the anchorage end. Both anchorages are at the same end.
Seeing Deklari is trying heat I have thought of trying to reform it using a gas soldering iron...but have no idea whether this will affect the quality of the spring itself (and I'd just burn my fingers!).
Another thought. Watchmakers or watch and clock restorers. Does anyone have a contact?
Michael
The problems I see are:
1) We do not have a good spring to copy. The thing is an awkward double spiral that turns back on itself
2) The chances of deforming the springs during installation are high. OK so my dexterity is nothing like Deklari's but I fear we would mess up a few before we had an acceptable result. The anchorage to the shaft is also very fiddly.
It is interesting that neither Deklari's nor my spring are actually broken. As far as I can tell it looks as if the outer coil or spiral which is unsupported has collapsed towards the anchorage end. Both anchorages are at the same end.
Seeing Deklari is trying heat I have thought of trying to reform it using a gas soldering iron...but have no idea whether this will affect the quality of the spring itself (and I'd just burn my fingers!).
Another thought. Watchmakers or watch and clock restorers. Does anyone have a contact?
Michael
Deklari
Well-known
Michael, It is correct both anchorage are at the same end (this how it designed). Also heating will defiantly result the quality. I just play around, it is nothing to lose. I personally see only one solution, re-place the spring from working Kiev or Contax II/III. P.S. And sorry I should tell what it really hot.
Deklari
Well-known
Erik van Straten
Veteran
What I know, is that when you have in 2016 a working camera with original straps they break almost instantly in use. I think they do not break because of wear, but because they desintegrate from age and the influence of lubricants.
Erik.
Erik.
Erik van Straten
Veteran
Contax I v7, Jupiter 8M 50mm f/2, 400-2TMY.
Erik.
Erik.
Deklari
Well-known
Excellent work !! Contax I and Jupiter 8m grate combinationContax I v7, Jupiter 8M 50mm f/2, 400-2TMY.
Erik.
That's an interesting point. I tend to agree with you. The first Contax II I changed the ribbons of was a 1936 model. The ribbons were very weak. They looked quite OK, but when you applied some tension to them, they disintegrated. The fibres no longer had any structural integrity. They were too old. The last one I did was a one owner Contax II I bought it. I have the ribbons, intact, from this one. I picked the stitching apart and extracted them from the curtains and the rollers. These are not falling apart. They feel quite strong and look in sound condition. Same colour, same weave, same blue thread used in the stitching that I have seen in other Contaxes with genuine ribbons. This example is also a 1936. How odd. If you didn't know better you might have been tempted not to replace them. I did, of course, with Aki Asahi material, for peace of mind. Two Contaxes, same year of manufacture, same material, ribbons in completely different condition. No conclusions I can come to about why they have aged so differently. I have no idea. Just reporting what I've observed.
Cheers,
Brett
