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Tylerwebb
Tinkerer
Username: Tylerwebb
Post Number: 1
Registered: 07-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, July 07, 2010 - 10:01 pm: | 
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I'm new here, just getting into restoring old cameras. I've been into photography for a long time and have a few old Medium format cameras, but have just started trying to really understand how to make them work. Great forum, already learned alot from here.
Anyway, I just got a Welta Perfekta Folding TLR from a local antique shop. Maybe the best $20 I've ever spent! Made in Germany in 1934 and in really excellent condition, no major cosmetic damage and only this one issue that I can find.
Compur-Rapid shutter mechanism.
The shutter is having an intermittent issue with Jamming open, and with the timing being way too fast.
The Jamming open is somewhat rare, maybe 1 in 100 shots. Recocking shutter a few times generally solves the problem. The Bulb setting does not work. The Timer setting will not even rotate into place. The little arm that the Timer Ring rotates up, which sits at about 12:00 as far as its position goes, hits the channel. I can't quite understand how this is supposed to work.
The other problem: Most of the time the timing seems right on, or at least close enough to get into line with a little calibration. However sometimes the timer "slips" and seems to go at about 1/100th of a second. This is regardless of my shutter speed. I could fire at 1 second successfully 10 times in a row, and then suddenly it will slip. When it slips once it will continue slipping every single time until I made a large adjustment to the timing, ie from 1 second to 1/25.
I think I know the reason for this:
The gear with the coil in the Slow Speed Escapement seems to be missing a tooth, or at least 1 tooth is worn down to about 0.1mm whereas the rest are about 1mm tall. When the next gear in line hits this gap between effective teeth, it slips. It subsequently slips every time until a change is made to realign the teeth. I have tested this by playing with the slow speed escapement out of the camera, setting it and firing it with my fingers repeatedly. Occasionally it will begin slipping as described and every time the gears are aligned with the next gear over sitting in the the gap between teeth on the spring gear.
http://farm5.static.flickr.com/4140/4773528712_0e9e6c620d_b.jpg
My question then:
If I buy a parts camera with a compur-rapid shutter, would the gear be compatible? What about the whole slow-speed escapement mechanism? Or is this even my problem? The short tooth seems to be too evenly worn to be an accident. I am very confused. |
Ron_g
Tinkerer
Username: Ron_g
Post Number: 36
Registered: 07-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, July 08, 2010 - 03:35 am: |
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On my Compur-Synchro escapements that coiled spring is anchored to a post with a slit in the top for the spring to slide into to hold it.It is possible to assemble the escapement without that spring being anchored properly thinking that the end of the spring might just catch on the post to hold it.If that spring was not properly secured and it slipped by the post I can see it affecting the performance similar to what you are experiencing.It would need to rotate nearly a full revolution before it caught the post again.
This may or may not apply to you as the escapement that you pictured is somewhat different than the ones that I have experience with.Ron G |
Tylerwebb
Tinkerer
Username: Tylerwebb
Post Number: 2
Registered: 07-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, July 08, 2010 - 01:37 pm: |
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The spring or coil on this gear is held securely to the small tab that can be seen in the photo. It seems to be either pinched or soldered or something from what I can tell, as it seems very secure. I have not removed this piece, and so I cannot say for sure, but I think the gear and coil are placed correctly. I am pretty sure that the problem is being caused by the missing tooth.
I am confused, since it seems unlikely that the tooth would have broken or worn in this fashion, which makes me think someone could have done it on purpose. |
Ron_g
Tinkerer
Username: Ron_g
Post Number: 37
Registered: 07-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, July 08, 2010 - 02:03 pm: |
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I would imagine that you could find a parts camera with just what you need on it without too much trouble.There are a lot of those shutters out there.I just sent a part to a fellow in Russia based on a picture that he posted but it turned out to be the wrong size.The Sychro-Compur was made in different sizes but apparently the parts look the same in the shutters,just larger or smaller depending on what you have.Good luck with it.Ron G |
Tom_cheshire
Tinkerer
Username: Tom_cheshire
Post Number: 331
Registered: 04-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, July 08, 2010 - 03:05 pm: |
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I'd love to have one of those for my shelf even if it didn't work at all. It just has to look reasonably nice.
Will you swap it for something?
Tom. |
Tylerwebb
Tinkerer
Username: Tylerwebb
Post Number: 3
Registered: 07-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, July 08, 2010 - 06:29 pm: |
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It is indeed a beautiful camera. I don't think I would trade it for anything at the moment. Thanks though. Send me a PM to chat about it a bit.
Oh and Nevermind about the Timer and Bulb settings not working. I feel really dumb. Obviously I don't need to cock the shutter when using T and B, it works fine I was just trying to cock it first for some reason.
After further cleaning and disassembly, I am quite certain that the entire problem with this camera lies in that one tiny tooth being broken. I noticed the tooth was still in place, just kind of folded down. Attempting to unfold it back into proper position caused it to break away completely. No worse than before and confirmed that it is the problem. Now to figure out how to get a new one... |
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