Yashica 635 Copal MXV Shutter Repair - DIY

ChristopherCoy · Jun 13, 2020

Back in March, I found this 635 on eBay. From what the seller posted, and the photos, it looked extremely clean and well taken care of. I figured I'd give it a go. She was overpriced, and I low-balled her, and we ended up meeting in the middle - which was still more than I wanted to pay, but I did it. It has the 4 element Yashinon Lens instead of the original 3 element Yashikor, which is why I wanted it. When I received it the shutter was completely inoperable. I requested a refund, she said I agreed to an "as is" sale, I disagreed, but she finally agreed to grant the refund if I mailed the camera back to her. I sent it back the day after it was received.

Two days later, after some long thought, reflection, and review of our complete transaction, I realized that I had misunderstood one of her messages. At that point I sent her a message, explained my misunderstanding, profusely apologized, and told her to keep the money and the camera, and have it repaired. The camera was a gift from her late grandfather, and she was selling it for extra money to live on since she had lost her job. She lived in Brooklyn as well, so I figured being in in the epicenter of the pandemic, she probably needed things more than I did. She kept up communication, and decided to send it back to me, which was very gracious of her. I received it today, a second time.

The shutter was still inoperable, and I decided "well, what's the worse I can do?" So I looked up some youtube videos, found a couple manuals online, and got out my screwdrivers. As it turns out, someone completely sheared off the self timer lever and the self timer mechanism was keeping the shutter from opening and closing properly.

I opened up the shutter and was eventually able to release the self timer mechanism, and was able to get the shutter to operate at all speeds. The article I found showed me how to remove the self timer mechanism all together, but I wasn't able to completely get it out... yet. My problem is that I can't get the flat side of the mechanism towards the lens, to lift it straight up.

Additionally, the weirdest thing occurs. I can get the shutter to cock, fire at all speeds, and operate functionally while the shutter is completely taken apart. But when I put the cam, cover, and retaining ring back on, it goes back to not opening/closing.

Any thoughts/advice/tips?

shutterfinger · Jun 13, 2020

Something you had loose inside the shutter is not seated properly, the cam is not properly engaged or the retaining ring is being tightened too much.
I have seen pins or levers that are flush to the cam/speed ring top when the ring is installed correctly but will sit under the ring if overlooked.
Another possibility is the case is bent from a drop.

ChristopherCoy · Jun 13, 2020

Ok. I got the self timer mechanism out, and the shutter is opening/closing properly.

I've got the camera back together for a third time, but now the shutter isn't staying cocked. I think it has something to do with the shutter button spring and button. Something isn't lining up.

Uh this is tedious work.

Donald Qualls · Jun 13, 2020

ChristopherCoy said:
Uh this is tedious work.

It can be. Especially if you've never had a leaf shutter open before. Sounds like you're making actual progress, though. Good luck!

ChristopherCoy · Jun 13, 2020

Donald Qualls said:
It can be. Especially if you've never had a leaf shutter open before. Sounds like you're making actual progress, though. Good luck!

Yeah, I closed it back up until tomorrow. I didn't want to get frustrated and do major damage. At this point a camera repair center can still save it, albeit without the self timer. I'll open it back up tomorrow and see what happens.

Donald Qualls · Jun 13, 2020

ChristopherCoy said:
Yeah, I closed it back up until tomorrow. I didn't want to get frustrated and do major damage. At this point a camera repair center can still save it, albeit without the self timer. I'll open it back up tomorrow and see what happens.

Probably a good move. Applying excessive force anywhere can do some harm, and replacement parts for fifty year old cameras aren't assured.

dxqcanada · Jun 13, 2020

Servicing a Copal shutter is not all that difficult if you are willing to learn. After a while it becomes "easy".
If you want to learn, I suggest: https://learncamerarepair.com/index.php

ChristopherCoy · Jun 13, 2020

dxqcanada said:
Servicing a Copal shutter is not all that difficult if you are willing to learn. After a while it becomes "easy".
If you want to learn, I suggest: https://learncamerarepair.com/index.php

I don’t have any interest in learning, I just wanted to see if I could save myself the $125 repair fee.

ChristopherCoy · Jun 14, 2020

Donald Qualls said:
Probably a good move. Applying excessive force anywhere can do some harm, and replacement parts for fifty year old cameras aren't assured.

Got it! The spring for the shutter button was behind the trip lever, causing it to always keep the lever depressed.

Now I just got to figure out where to lube, and what to lube with. It's been stuck so long that the shutter speeds are off. At first glance it looks like the blades may be a little sticky, but I'm not sure. There's some moving gears and lever that appear to get sluggish.

campy51 · Jun 14, 2020

I can tell you the improper way to clean the shutter but most will not recommend it. I use an electronic spray to fix copiers and printers and used it on my first shutter and it worked well. It takes a while but you only need to take the speed dial off and of course take the elements out. Spay the crap out of it until you think it's been flushed of all dirt and oil. You will have to keep spraying the blades also but you will get to a point where you can clean the blades individually very gently with the electronic spray and a lint free cloth until everything is nice and snappy. The electronic spray I use leaves no residue. Then I use a very small amount of sewing machine oil applied to the top post of the of each moving part. It's better to have not enough oil than too much oil. Remember this is not the best way but I did it because a cleaning cost much more than I paid for the lens and was willing to throw it in a box if I screwed up and look at it as a training lesson.

Donald Qualls · Jun 14, 2020

Blades need to be absolutely dry, or the slightest touch of dry graphite or molybdenum disulfide (some rub a little with a soft pencil). For the shutter mechanism, you want high quality very light oil (sewing machine oil used to be good, now it's hard to find because modern machines aren't made to be oiled). NOT 3-in-1! Applied in fractional drops with a sewing needle (best) or toothpick (usually acceptable) only on the bearings the gears turn on. Cleaning those gears and their bearings before lubricating would be preferred, but doing that properly requires additional disassembly. If the shutter runs now, and given you aren't interested in learning to service Copal shutters in general, I'd get a bottle of the right kind of oil, put the tiniest amount you can manage on the bearings of each gear (nothing on the teeth, it'll just sling off and get where it isn't wanted), clean the blades with naphtha (wick type lighter fluid works) until they dry with no visible oil, and then test the shutter and record the actual speeds.

@campy51 actually has a reasonable method -- I use a product labeled as "CRC QD Contact Cleaner" at work (not on cameras), it's residue free (nearly pure heptane, which is effectively naphtha in a spray can) and easy/quick to apply. There are similar products in other brands, possibly available at auto parts stores. DO NOT get brake cleaner of any sort; you want "quick drying contact cleaner" for electrical parts.

ChristopherCoy · Jun 14, 2020

Cool. I've got some thinking to do and decisions to make. I've made it this far and at LEAST got it working again. And I have another 635 that I can sacrifice for parts since it has a working shutter, should the worst happen. I just have to determine which is more valuable, the learning experience, or the $80 CLA fee at the repair shop.

campy51 · Jun 14, 2020

ChristopherCoy said:
Cool. I've got some thinking to do and decisions to make. I've made it this far and at LEAST got it working again. And I have another 635 that I can sacrifice for parts since it has a working shutter, should the worst happen. I just have to determine which is more valuable, the learning experience, or the $80 CLA fee at the repair shop.

$80 that's cheap, I would have gone that route.

ChristopherCoy · Jun 14, 2020

campy51 said:
$80 that's cheap, I would have gone that route.

The repair quote was $125, the CLA quote was $80. Now that it's working, it's just a matter of whether I want to clean it, or have someone else do a better job than I can.

shutterfinger · Jun 14, 2020

TriFlow https://www.amazon.com/Tri-Flow-Squeeze-Bottle-Lubricant-Teflon/dp/B00GC54OC2/ref=sr_1_2?crid=2P4V4004R7JE3&dchild=1&keywords=triflow+superior+lubricant&qid=1592165372&sprefix=triflow,aps,208&sr=8-2
CRC QD Contact Cleaner https://www.homedepot.com/p/CRC-11-oz-QD-Electronic-Cleaner-05103/205021975

No lighter fluid.
Oil drop about the size of a straight pin point at the green o's.

ChristopherCoy · Feb 3, 2021

I took it apart again today and tried the CRC electronic cleaner. While it did seem to dislodge some of the debris, it did a better job just mudding things up. The rear lens element now looks like I dragged it behind a truck on a muddy road.

I oiled the points with some Hopps #9 oil, and things got better, but then they got worse. They unstuck and I was getting full functionality, and then they'd get slow and sluggish again. I doused them with electronic cleaner again and they'd get better for a while, and then something would get stuck again.

I'm giving up again for another few months. I may just take the whole thing over to the camera shop and have them do a full CLA.

Or maybe I'll just make a lamp out of the damn thing.

BrianShaw · Feb 3, 2021

Lamps have been done. How about converting to a flashlight?

Kino · Feb 3, 2021

Try cleaning the shutter blades with 91% iso alchohol and cotton buds/Qtips, front and back.

Take out the rear element; shouldn't be hard.

Fire the shutter several times and do it again. Eventually, it will free up.

shutterfinger · Feb 3, 2021

It needs to be fully disassembled including disassembling the delay timing assembly, which can be difficult to reassemble and get the timing speed correct, soaked in cleaner or run through a few cycles in an ultrasonic cleaner then reassembled.

ChristopherCoy · Feb 3, 2021

shutterfinger said:
It needs to be fully disassembled including disassembling the delay timing assembly, which can be difficult to reassemble and get the timing speed correct, soaked in cleaner or run through a few cycles in an ultrasonic cleaner then reassembled.

Yeah. See what I heard was, “just bring it to the repair shop.”

shutterfinger · Feb 3, 2021

Be prepared to need a replacement shutter as that one may be worn out. You won't know for sure until its fully serviced.

dxqcanada · Feb 3, 2021

If you want to learn how to restore that copal shutter ... https://learncamerarepair.com/
There are specific lessons about these leaf shutters.
You can also ask on the FB group for help.
Its not that difficult, but you need to know the right way to do it.

removedacct1 · Feb 3, 2021

ChristopherCoy said:
I don’t have any interest in learning, I just wanted to see if I could save myself the $125 repair fee.

Speaking as someone who has learned to perform complete restorations on Retina cameras, I can guarantee you will have to learn some things if you expect to save yourself the cost of having it done properly.

ChristopherCoy · Feb 19, 2021

Ha!! Progress! Got the speed regulator out!! Only thing left is figure out how to get the shutter blades off for a cleaning.

ChristopherCoy · Feb 19, 2021

Oh oh... it’s on now.

Yashica 635 Copal MXV Shutter Repair - DIY

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