Part 2: CLA Extar 101mm f4.5 Synchro rapid 800 Shutter

[peter k.]

Well did some research and these Kodak Extar 101mm f4.5 Synchro rapid 800 Shutters are ... ah.. PIA.. as they are not dependable, most will not CLA.. so got nothing to lose... making it a learning curve..
Took it apart.. this was the start of Part 1:

(there was a url link here which no longer exists)

Part2:
Well it turned out that the spring I thought was broken wasn't, so I put it away for a while and started on it again this last week. It's been a very interesting learning experience,. Took it all the way down, and putting it back together and placing the speed ring on it, have found that the contact lever assemblies spring finger is bent and almost ready to fall off. Because it is bent inward, it is preventing an adjustment to the lower speeds, as it stops the speed ring from turning in a counterclockwise motion.

Question: How where these attached? Soldered on? If not how?

In the image, which shows the contact lever assembly, with the lens mostly dismantled. The spring finger is in the lower left hand corner.

 

[shutterfinger]

Please add an ARROW pointing to the part (tip of arrow at the edge of the part) you are referring to. I think I know which part. To place an arrow open the photo in photoshop, open character map (windows), select wingdings as the font, select the arrow best suited, select, copy, select text tool in ps, select wingdings as the font, place the cursor where you think is correct, right click-paste. Position correct-click OK and save, position incorrect-click on the no circle with red slash, reposition the cursor and try again.

The lever may be spot welded to the case. Soldering it may be an option. I could be outside the ball park with the part.

Edit: It might help if the picture showed both ends of the spring.

 

[peter k.]

Was thinking could be careful, and use a tooth pick tip of JB weld. Done of course with the part removed.



BTW Using windows XP Character Map is already there under Programs, Accessories, System Tools.

 

[shutterfinger]

With the part removed clean the case side with fine sandpaper or similar. Cut a strip of .010 to .015 inch brass shim stock to fit 1/4 inch beyond the weak spot or end to 3/8 inch down the length of the part, tin both with solder leaving a thin flat layer of solder then solder them together with pressure to keep the solder layer thin. JB Weld does not hold up well in flex situations for me.

Excellent picture.

 

[John Koehrer]

Looks like the contact is fastened to the moving lever..You might have some success silver soldering the contact in place.Regular solder won't hold.

 

[peter k.]

Well went back to it, and straightened the finger, by clamping with a needle nose at the spot where it meets the moving lever. Was surprised that it didn't break off, for it was bent more than shown in the picture. So went with the adage, .. if ain't broke (yet) don't fix it!
So put it all back together.. and it works, cocks and firers cleanly which was a pleasant surprise after how poorly it was doing before. Often it would not even fire, or get stuck.

Trouble is the shutter speeds are off.
Funny thing, in testing .. faster, on a curve, from fastest at 1sec, and then gradually getting closer to the mark, until it reaches its quickest speed of 5 milliseconds at about 200, which is right on.
Shutter is suppose to hit 800, ah I don't think is reality for an old lens.. or am I wrong?
Also I did not take apart the gear train assembly, that in my understanding sets the speeds. Would this have to be done to get it more accurate? Clean it and oil it slightly?

Your thoughts...

 

[shutterfinger]

Yes, cleaning the delay mechanism gear train should improve shutter speeds. I have never seen one of these shutters so I do not know how Kodak adjusted the speeds. On a Supermatic the retarding sector with stud distance from the case is set to a specified distance of Approximately 1/8 inch when meshed with the Sector gear of the delay mechanism. Good pictures of the delay in both full release and cocked position is your bet bet unless you have the service manual.

 

[peter k.]

On a Supermatic the retarding sector with stud distance from the case is set to a specified distance of Approximately 1/8 inch when meshed with the Sector gear of the delay mechanism. ...

Well it took me a while to figure out what you meant, as the gear train assembly cannot be adjusted but the tooth retard sector can be set differently, as it is placed back in with the gears that it meshes with.
So I had the unit cocked, and meshed the gears so gear was approximately 1/8" from the case.
Fired the shutter and re-cocked it, and it placed it as shown in the second image.

I have the service & repair manual with parts list with exploded views,, but can find nothing elating to the disassemble or adjustment of this. In several pictures it shows it as my images cocked or un-cocked.

 

[shutterfinger]

Supermatic with a 100WFE partially disassembled to show retard timing.

This is a #2 shutter, yours is a #1.
There are minor differences between #2 shutters according to the lens used. The Supermatic was used on Monitor 620 and Medalist cameras.

I try to use factory terminology whenever possible as referencing to the manual makes identification easier.

 

[John Koehrer]

1/800 on any leaf shutter was just a wish and advertising gag.

 

[shutterfinger]

1/800 on any leaf shutter was just a wish and advertising gag.

I would challenge you on that but I was not into photography let alone testing shutters when the equipment was new. I do have a Super Speed Graphic with the 1000 Graphic shutter. I did a CLA on the shutter then it sat in the camera case for 10 years before I tested it. 1/1000 was 1/2 stop slow; 1/750 was 1/750; 1/500 was 1/500. It has set for a few more years since the test but will likely be within 1/2 stop across the full range of speeds.
2 factors determine how accurate old leaf shutters are, 1. how much use they have been subjected to, and 2. how they were treated.
Like everything mechanical there is a wear limit. Running a shutter beyond when they have slowed 1/2 stop on speeds will weaken the springs as much or more than heavy use with frequent CLA's.
I have serviced low use shutters that were not run dirty to come back with the 1/250 within a half stop of perfect and the 1/500 speed between 1/250 and 1/500. Coming across this good of a shutter is getting rarer but it does happen.
Heavy wear or run dirty until it stops shutters are lucky to get the 1/50 within 1/3 stop on a shutter with a top speed of 1/500.
Spring fatigue is the most common weakness followed by pivot wear.

 

[Hatchetman]

Paul Ebel did a CLA on my Supermatic 800. 1/800 times out at 1/400 which is fine by me.

 

[sfaber17]

Running a shutter beyond when they have slowed 1/2 stop on speeds will weaken the springs as much or more than heavy use with frequent CLA's.

Could you explain why the springs would weaken more in that case?

 

[shutterfinger]

Running a shutter dirty increases the friction of moving parts. With fine grit in the pivots they wear faster. In a clean shutter parts moved by spring tension go from tensioned to relaxed quickly. It a dirty shutter the parts move slower keeping the spring under tension longer.

 

[BrianShaw]

Are you certain that time under tension reduces the elasticity of a spring?

 

[shutterfinger]

Are you certain that time under tension reduces the elasticity of a spring?

No, just reporting what I have found to be true with the shutters I've serviced. Springs in shutters that were run until they stopped or were close to stopping have 10% to 15% less tension than a same make shutter that has low use or was serviced at 1/2 stop slow.

 

[BrianShaw]

Spring condition is just one of many factors. Too loose a pivot or too tight of a pivot = friction. Too much or too little lubrication = friction. Imperfect cleaning = friction. Any minuscule gouging/wear pattern in the pivot hole = friction. Some oils are better than others in terms of lubrication. All of this, plus the spring tension and more, can affect the maximum speed of the total mechanism. Even with perfect spring capability Its rather complex....

 

[sfaber17]

I would submit that perhaps the effect seen is that a shutter sets for 10 years or so and then is found frozen or sluggish and is sent in for a CLA, and another is well used for 10 years so it doesn't get as stuck and isn't as noticeable, but is a couple stops off by the time it is sent in for a CLA and that one is found to be worn and the springs are fatigued probably from total number of cycles.

 

[shutterfinger]

Light use, stored shutter with dried out lube will restore to near new.
Moderate use routinely serviced shutters run a close second.
Heavily used routinely serviced shutters loose their fastest speeds.
Run until they stop then serviced shutters restore with the fewest speeds accurate/in tolerance.

 

[BrianShaw]

Light use, stored shutter with dried out lube will restore to near new.
Moderate use routinely serviced shutters run a close second.
Heavily used routinely serviced shutters loose their fastest speeds.
Run until they stop then serviced shutters restore with the fewest speeds accurate/in tolerance.

No doubt. All I'm suggesting is that these observations are caused by additional factors, not just fatiguing springs. That's exactly why a smart individual will service their gear (shutters, cars, boats, mechanical clocks/watches, and many other devices) long before they stop working. I think you would concur.

 

[shutterfinger]

Weak springs are the easiest failure to see in a shutter. I have seen shutters with worn pivots that were maintained have better springs than shutters that were not maintained and have better shutter speed accuracy up to 1/100.

For some reason wives tales and great grandpa's get it going in the field techniques are held as the repair standard that should be used and manufacturers specifications are exaggerations.

 

[shutterfinger]

Peter,
Have you played with any adjustments or varied any spring tensions that are adjustable to see if any improvement in speeds can be obtained?

 

[peter k.]

Well have no idea what adjustments I could make! Nor have messed with springs.

I've have become more familiar with the lens, but the only lubrication I've done is some powered graphite on the blades, applied softly against a hard back surface, with a Q tip, previously rubbed in the graphite. Then very light sewing machine oil, on tip of tooth pick, to the gear ends of gear train, delay mechanism, which I'm not up to yet in dismantling.
No oil was placed at the pivot points of the blades.. just left them alone.
In the repair manual under Lubrication it goes into detail of what needs to be done with oil and 'grease' Trouble is they are using references to places that have no reference to items in the manual.
So working on that, to get a better clarity, and may have some questions of what is what as I go deeper into it, and take it fully apart again, and try to do a real lubrication.
Have nothing to lose and this has been quite an interesting project, and on the first go around, got the shutter to fire consistently, and now will work on accuracy. Thanks and appreciate your support.

 

[BrianShaw]

Well have no idea what adjustments I could make! Nor have messed with springs.

I've have become more familiar with the lens, but the only lubrication I've done is some powered graphite on the blades, applied softly against a hard back surface, with a Q tip, previously rubbed in the graphite. Then very light sewing machine oil, on tip of tooth pick, to the gear ends of gear train, delay mechanism, which I'm not up to yet in dismantling.
No oil was placed at the pivot points of the blades.. just left them alone.
In the repair manual under Lubrication it goes into detail of what needs to be done with oil and 'grease' Trouble is they are using references to places that have no reference to items in the manual.
So working on that, to get a better clarity, and may have some questions of what is what as I go deeper into it, and take it fully apart again, and try to do a real lubrication.
Have nothing to lose and this has been quite an interesting project, and on the first go around, got the shutter to fire consistently, and now will work on accuracy. Thanks and appreciate your support.

Although there is some controversy with the graphite on shutter blades, what you've done so far isn't too far off from what's generally considered "proper". The spec and repair manual is probably very specific about oil. A watch oil may be better than light sewing machine oil... or not. Probably doesn't matter much really. The grease is one thing you have not mentioned in detail. Grease is to lightly lubricate sliding surfaces. Without it you'll not get the best performance out of the shutter. White lithium grease works just fine.

If you haven't completely disassembled you have no way to lubricate the "inside" pivots... making a shutter only half lubricated. In practices, half lubrication may be just enough to get it going again (even somewhat reliably) but not the best way to get full performance. Something to think about.

The repair manuals generally are specific about how each shutter should be calibrated. Sometimes it is as simple as setting up the 1-second to be within spec for 1-sec and the rest will happen via the design. When the calibration process in the manual fails, an advanced technique that few mention (or ever do) to get the speeds closer to accurate is to modify the speed cams in the speed ring. Time consuming and rarely worth it, but completely legitimate for shutter speed adjustment. Sometimes the top speed simply can't be restored because often it relies on the shutter operating at its maximum mechanical speed - which may require both springs that are completely within their specification value and a cleaned/lubricated mechanism that minimizes friction to the maximum extent. Both of these items have been in discussion but it isn't often one or the other... to get the true speed of the maximum advertised both are likely to be required. Since that is a challenging set of circumstances to ensure in older shutters, many of us consider it good enough to be within 1 stop for the top speed.

But honestly, a lot of this is just not really required to get an old shutter going enough for use in every day photography. If one needs reliability more might be needed... like a proper teardown CLA. For almost anything else a little testing and correction of exposure/processing settings will compensate for a less-than-perfect shutter. If you got it running reliably, my suggestion is that you pat your self on the back and go shoot some pictures!

 

[peter k.]

If you haven't completely disassembled you have no way to lubricate the "inside" pivots...

Well I fully disassembled it, but didn't get into lubrication, just wanted to see if I could get it running again

The repair manuals generally are specific about how each shutter should be calibrated.

The manual talks abut bending this or that to get what you want.. but nah.. not going there .. ah yet.
I'm not worried about top speed, right now it firers when on 800 at a 400 speed which is fine with me.. its the lower speeds that are running fast of all things.. not slow! As it gets up to 100 or so, it comes much closer to the correct speed. But not consistently. For some reason set a 50, its way out of wack and slow.
Its funny with these lenses in adjusting them to speed, there is no notch.. but if you cock the shutter you can 'feel' the point often on the cam, for that speed.
Doing another tear down and lubricating it should help, this is really the first CLA Ive done, although I got a locked Yashica YK lens that was all gunked up to fire and shoot some picts.

For almost anything else a little testing and correction of exposure/processing settings will compensate for a less-than-perfect shutter.

Yes.. on my other older shutters, I have just excepted them as they are, and have a note attached to the camera, that 125 is actually 200 setting ect. Works fine and consistent.
.