Contax shutter problem

[darkkavenger]

Hello,

I've owned a Contax III for a while that has problem that it already had when I purchased it : shutter is firing at the same speed (seems to be 1/250s) regardless of what speed you select, except B of course.

So today I don't know what mosquito bited me and I decided to disassemble it to check what is wrong. According to you, where could something go wrong? maybe it is a gear that isn't engaging properly ?

Thanks for your hints and advices ! 😀

Max

 

[FrankS]

Good luck with this Max! You are braver than I.

 

[darkkavenger]

Thanks Frank! I don't know if it's bravery or curiosity! I guess it's the energy that keeps the world in movement : seeing what's "behind/below" 😉

 

[darkkavenger]

*bump* thanks 🙂

 

[varjag]

Max, there is a slow speeds escapement that engages when shutter is set to slower than 1/125. From what it sounds, that one most likely not doing its job.

There are some sites out there that illustrate the principles of Contax shutter; Maizenberg book might also have some. All information to Kievs is about just as applicable.

I think though that the best way would be to open a Kiev with functioning shutter, and compare movements involved in wind action. Contax shutter workings are fairly hard to visualize from pictures.

 

[Wayno]

It sounds like the escapements aren't being engaged. From memory there are two sets of escapements - one set is bought into action at 1/50 & 1/25 (?) and a secondary set for the slowest speeds. Have a look at this page of the Kiev survival, which shows how the escapements are engaged. Something may be sticking and preventing the escpaments from engageing. If you pull the shutter and give the mechanism a good clean it may start working. Alternatively there may be a broken or displaced spring - there are a few which hold the levers/escapements in position. BTW you should be getting a few different shutter speeds even if the escapements aren't working because the slit width between the two curtains varies as you change speeds.

 

[darkkavenger]

Thank you Eugene & Wayno, I will check this. What was crazy is that even at 1/2, it was firing as if it was at 1/250s (I assume it is 1/250s, but it could be as well 1/125 or 1/500).

Will check for more ...

 

[rxmd]

Maizenberg has a very detailed section on shutter repairs, p. 253 to 265 in the English edition, with a troubleshooting guide. Since the Contax is nothing but a Kiev clone under a Capitalist brand name, I guess that would help.

On grounds of yesterday's conversation I'm assuming that you have a copy of Maizenberg ready. (I think you have the English version, but the Russian is floating around the web somewhere in an excellent scanned PDF version.) If you are not sure that it's 1/250, i.e. if it might be 1/125 as well, your description of the problem could indicate a problem with lever arm 10 in picture 324f, causing problems with the escapements at speeds under 1/125. See accompanying text on p. 260 below. Otherwise I would second Yevgeni's suggestion of looking at a functioning Kiev to see how the speeds mechanism should work.

Is "B" working?

 

[darkkavenger]

Hi Philipp, I will check through Maizenberg's book... B is working correctly 🙂

 

[darkkavenger]

I hope it wasn't a mistake to undergo this.. its quite complex

 

[Pherdinand]

it is quite complex but it is built modular so reassembly is relatively easy (if you tyook notes or have a good memory of course).
I don't understand however why the fast speeds would also not work different than 1/250-ish. Their "speed"is not dictated by an escapement gear train, it's only dictated by how far the first shutter blind is wound up on the top shutter roll. This happens after they travel together to the top and they get uncoupled by the little funky levers on the side, while the bottom curtain is kept in place by the flimsy elastic brass lever in the top middle, these features are visible already with only the film gate being taken off.

Good luck.

 

[Xmas]

Max

The first thing to do it to reattach the winder speed selector this will allow you to wind and select a new speed. But you have to be real careful.
It is likely the camera is firing ok 1/125 and faster, if the slow speeds are not operating the first think to look for is - is the cam that alters the speeds turning?
This cam is not easy to find, so you need the Kiev survivial site...
I cannot visualise any mechanism to prevent this cam turning, and the camera still being able to fire, but there might be.
Russ Pinchbeck indicated that taping over one of the shafts is necessary to avoid the shutter falling into smaller pieces, so you probably need to do this.
Good luck

Noel
P.S. the little clock escapments are easy to find and a really gentle nudge from tip of a dentists pick could be tried, if they jam the normal result is every thing locks up solid...

 

[Xmas]

Max

The speed selector cam is detailed on figs 21-24

http://cccp.webstar.nl/kiev2rep_1.htm

Noel

 

[darkkavenger]

Thanks Noel & Pherdinand! I will check this tomorrow, with plenty of sunny "available light" and "available brain" 😉

 

[Xmas]

Max

If your camera is the same as the diagrams (for each speed) then the 2nd blind is not being retarded.

Noel

 

[2tcreative]

Contax III shutter problem

Contax III shutter problem

Check out Henry Scherer's new site at this url: http://www.zeisscamera.com/services_overhaul-cII-shutter.shtml

may give you a hint. If not, you might email him and see what direction he could give you.

 

[darkkavenger]

Hello f2eyelevel, the spring is there and in place. I am trying to get some photos which show the dysfunctions on the shutter. It's quite intriguing!

 

[darkkavenger]

The small gears do not move freely under fingers, are those located under/ tho the left of the winding knob ? i have selected B which works, but when I try 1/2 or 1/5, it goes considerably faster. also, the big wheel turns when I am winding after firing the (too fast) 1/2s.

should these small gears move?

 

[Xmas]

Max

You are testing my memory...
When you wind on with a slow speed selected, the small gears should move, as you wind.
When you fire the shutter if you have selected a slow speed one of the two escapments (or both) should buzz and then release the second blind.
The only simple way is to strip two shutters, one working one broken.
But dont break anything it may take a while identifying a problem.
The escapments the claw devices that span the teeth on the ends of the shaft they should be free, (they wont move more than a few degrees) zippo their shafts, and apply small drop of oil, they should run dry but we will have to get the mechanism to work and then worry about the light oil.
The shafts that have the exposed teeth (which wooble the escapments) will be under tension or latched they should turn when winding or selecting a slow speed.
I'll check this for you and post tomorrow.

Noel
P.S. the escapments are next to the internal speed selector in the diagrams referred to earlier...
P.P.S. My English is not perfect
http://www.bricksandbrass.co.uk/decfeat/dfclock/clkescape.htm

 

[darkkavenger]

Thanks Noel, so far I have the shutter blinds still attached, I don't dare to bring the camera apart further. I'll see how it goes, it might take me weeks, even months, but I'll see 🙂