kb244
Well-known
I was wondering if there was any kind of grease/lubricant/etc involved in cleaning the shutter assembly of the Mercury II. I have one that works, nice clean glass, but the shutter speeds are off in the higher range (like over a stop off).
Testing with a phototransistor at the back of the camera thru the lens with an LED flashlight in front (alkaline battery so it doesn't flicker). Which was odd to me because the Mercury seemed to have a very high reliability when it comes to their shutters.
Speed on Dial = Measured Speed (Approximate deviation)
1/1,000 = 1/196.3 (+2 1/3)
1/300 = 1/158.5 (+2/3)
1/200 = 1/99.4 (+1)
1/100 = 1/74 (+1/3)
1/60 = 1/47.5 (+1/3)
1/40 = 1/31.3 (~1/3-ish)
1/30 = 1/25 (+1/3)
1/20 = 1/15.5 (+1/3)
The diagrams here shows how to get the shutter assembly out completely:
http://rick_oleson.tripod.com/index-210.html
As stated on the top "Generally, all the shutter needs is a bit of oil on the main spindle.", just trying to figure out from the diagram where the main 'spindle' is, and what kind of oil would be best (cuz I'm assuming it's not like WD-40).
The shutter speed itself I thought is simply a gap distance between the two discs, and they just travel as one piece when the shutter is fired. So course I'm thinking that if I can get that cleaned/oiled, maybe at least the 1/100 ~ 1/300 range would get back closer to marked speed.
It seems like I can oil the spindle by just removing the rear cover at top, and cocking the shutter and setting it to "T" to expose most of the top. Assuming that I can do that without disassembling it, relatively speaking it seems pretty clean in there. The gears as they turn don't seem to have any kind of crud on them.
Testing with a phototransistor at the back of the camera thru the lens with an LED flashlight in front (alkaline battery so it doesn't flicker). Which was odd to me because the Mercury seemed to have a very high reliability when it comes to their shutters.
Speed on Dial = Measured Speed (Approximate deviation)
1/1,000 = 1/196.3 (+2 1/3)
1/300 = 1/158.5 (+2/3)
1/200 = 1/99.4 (+1)
1/100 = 1/74 (+1/3)
1/60 = 1/47.5 (+1/3)
1/40 = 1/31.3 (~1/3-ish)
1/30 = 1/25 (+1/3)
1/20 = 1/15.5 (+1/3)
The diagrams here shows how to get the shutter assembly out completely:
http://rick_oleson.tripod.com/index-210.html
As stated on the top "Generally, all the shutter needs is a bit of oil on the main spindle.", just trying to figure out from the diagram where the main 'spindle' is, and what kind of oil would be best (cuz I'm assuming it's not like WD-40).
The shutter speed itself I thought is simply a gap distance between the two discs, and they just travel as one piece when the shutter is fired. So course I'm thinking that if I can get that cleaned/oiled, maybe at least the 1/100 ~ 1/300 range would get back closer to marked speed.
It seems like I can oil the spindle by just removing the rear cover at top, and cocking the shutter and setting it to "T" to expose most of the top. Assuming that I can do that without disassembling it, relatively speaking it seems pretty clean in there. The gears as they turn don't seem to have any kind of crud on them.
tunalegs
Pretended Artist
For a camera like this you could use sewing machine oil, or even 3-in-1. The spindle is the spindle thing in the center of the shutter disk.
You might try a dab of white grease on the gears as well.
You might try a dab of white grease on the gears as well.
davidnewtonguitars
Family Snaps
Tri-flow oil makes a pin-point lubricator that, looks like from your picture, could touch almost every bearing part.
The main spindle is the one with the shutter leaves rotating on it.
I would try to wash out all the metal filings floating around in there beforehand, using a brush and Ronson lighter fluid.
The main spindle is the one with the shutter leaves rotating on it.
I would try to wash out all the metal filings floating around in there beforehand, using a brush and Ronson lighter fluid.
kb244
Well-known
Bonus points if I can do so without having to take it apart.
I assuming you mean this :
Seemed more like dust, which I have blown out some more afterwards. Not seeing anything that seems like shavings, or reflective little bits of filings.
Good tip on a lubricator that can get in there without having to take off the whole front assembly.
Seems like the only reason you would need to take the whole front off, is so that you can get at the four screws on the side of the shutter housing to take off the back cover.
Also I was thinking... the shutter on the Mercury II is a rotary type in which the 1/1,000th speed is going to be a very tiny slit, and the disc probably doesn't move quite as fast as that, just the exposure of the slit does. It also seems like there is a small deviation of speed difference between measuring the top, center, or bottom portion of the frame.
Is it possible that phototransistor (from photoplug.de) being a large enough diameter is not accurately reading the shutter speed accurately above 1/60th because it's getting more light as the slit passes by a different portion of the "eye"?
farlymac
PF McFarland
I used lithium grease on mine, but if I had to do it over I'd use Super Lube, a synthetic you can get at the hardware store.
You're going to have to lube the winder too, maybe even the shutter speed selector. Plus, with all that dust/shavings you are getting out of the camera now, you might as well tear it down, and do the job right. It will give you a chance to clean all the crevices inside, and repaint the interior.
http://www.rangefinderforum.com/forums/showthread.php?t=117350
PF
You're going to have to lube the winder too, maybe even the shutter speed selector. Plus, with all that dust/shavings you are getting out of the camera now, you might as well tear it down, and do the job right. It will give you a chance to clean all the crevices inside, and repaint the interior.
http://www.rangefinderforum.com/forums/showthread.php?t=117350
PF
kb244
Well-known
Eventually perhaps, but I'm trying to avoid having to remove the front stuff if I can help it. I don't want to screw up the focusing helical.
This is the speeds (tested at top and bottom of the frame because the slit differs at those areas, Richard said the bottom of the frame is likely to be more accurate in regards to the phototransistor) after dabbing a little bit of zippo lighter fluid around the spindle area and rotating/shot-off a few times, with changes in shutter speed to get it in between the spindle core.
At the top-center of the frame
1/1,000 = 1/331
1/300 = 1/197
1/200 = 1/130
1/100 = 1/78
1/60 = 1/50
1/40 = 1/33
1/30 = 1/27
1/20 = 1/16.4
At the bottom of the frame [larger slit], did these after I did all the above
1/1,000 = 1/365.8
1/300 = 1/220
1/200 = 1/125
1/100 = 1/88
1/60 = 1/53.5
1/40 = 1/36
1/30 = 1/28
1/20 = 1/17
Original testing before uncovering the top and blowing it out (and before the little bit of lighter fluid)
1/1,000 = 1/196
1/300 = 1/158.5
1/200 = 1/99
1/100 = 1/74
1/60 = 1/47.5
1/40 = 1/31
1/30 = 1/25
1/20 = 1/15
Edit: Shutter assembly is out of the body now, as it stopped spinning (like it lacked spring tension), so like, might as well get it open.
Also noticed several small pieces of film, like where the sprocket hole may have been ripped sitting inside near the rewind knob gears.
Tomosy covered the model in one of his repair books. May be worth chasing a copy of it. Also checking the old CCRF repair archives hosted here.
Cheers
Brett
Cheers
Brett
kb244
Well-known
Noted.
I went ahead and disassembled it as I find out why it lost it's tension all the sudden. For the time being I put all the parts away into my dark box.
Rick has some notes on the model, too. If they're not up on his site, you might try dropping him a line.
kb244
Well-known
He's been in contact with me last night.
I reassembled it after I cleaned out some crud that seemed to be stuck behind one of the gears keeping the spring from coiling freely. But course the speeds seem about the same, however I have not tried any lithium grease yet on the points mentioned in farlymac's post/site. So will see if either Ace or Lowes are open tomorrow and find that "super lube", or similarly a lithium grease with a high/low temperature tolerance.
After reassembly and swabbing any cruddy areas, etc. But not yet greased/lubed. (done three times each to watch for sporadic changes)
1/1,000 = 1/365.3, 1/354, 1/369.3
1/300 = 1/156, 1/158, 1/152.6
1/200 = 1/122, 1/130, 1/117
1/100 = 1/77, 1/76.5, 1/76.4
1/60 = 1/49.6, 1/49.0, 1/50
1/40 = 1/32, 1/32.2, 1/32.8
1/30 = 1/24.5, 1/24.9, 1/24.4
1/20 = 1/15.7, 1/15.8, 1/15.8
02Pilot
Malcontent
Super Lube is a synthetic grease. Very good for gear teeth, but also fairly light - use very sparingly so it doesn't migrate and make a mess of things. Use a needle applicator to apply light oil to each spindle where it mounts; I prefer Breakfree CLP in this application, but any gun or sewing machine oil will be adequate. Finally, if you have surfaces where metal parts slide together under pressure (I'm not familiar with the Univex), apply an extremely fine layer of molybdenum grease (commonly used in CV joints); this layer should be so thin you can't see it.
Steve M.
Veteran
This falls into the category of "if it ain't broke, don't fix it". A shutter that runs one stop slow at the higher speeds is actually considered to be in spec. You won't see any difference in your shots unless you shoot chromes. Just make allowance for that one stop when you shoot if it concerns you, since you'll be hand metering anyway. Yours seems to be running 1 1/2 stop slow at 1/1000, and is at spec below that if your tester is accurate. Very typical for an old camera regardless of what sort of shutter it has. This is why I always looked for Rolleicords and folders w/ top speeds of 1/500 to shoot, because I knew that they would only be somewhere around 1/200-1/300 when set to 1/500. If you shot something w/ a top speed of 1/300 on the shutter, you were going to have problems because that was inevitably going to be only 1/100-1/175 in real life.
The only time I saw speeds that were close to accurate at 1/500 and above were on newer cameras w/ electronic shutters. Most times a CLA will not necessarily improve things, it will just let you know at what speeds the shutter is actually firing at. Just like us, cameras get old and slow down a little :]
The only time I saw speeds that were close to accurate at 1/500 and above were on newer cameras w/ electronic shutters. Most times a CLA will not necessarily improve things, it will just let you know at what speeds the shutter is actually firing at. Just like us, cameras get old and slow down a little :]
farlymac
PF McFarland
Shoot, mine was full of sprocket flecks! Yours is pretty clean on the inside, no corrosion visible.
I tend to not get very worried about shutter speed accuracy on old cameras, unless it shows up on the negatives. Most B&W films have good latitude, and even some of the color ones. Chromes are problematic, but since there isn't much available at the moment (and no, Kodachrome isn't coming back), and it's unlikely you'll find a decent stock of half frame slide mounts, you can discount the chance of over exposing your images.
PF
I tend to not get very worried about shutter speed accuracy on old cameras, unless it shows up on the negatives. Most B&W films have good latitude, and even some of the color ones. Chromes are problematic, but since there isn't much available at the moment (and no, Kodachrome isn't coming back), and it's unlikely you'll find a decent stock of half frame slide mounts, you can discount the chance of over exposing your images.
PF
gb hill
Veteran
sevo
Fokutorendaburando
It's little more than 2/3 off, towards overexposure too. It may not have been much more accurate when new. Segment shutters are torque monsters as far as camera shutters go (as the pivot point bearing is at the slowest travelling spot), so they are much less affected by dirt and corrosion than leaf or curtain shutters.
kb244
Well-known
least I got rid of that vibrating drag feel I get seldomly (or almost always if I pointed the camera up).
It's still disassembled (though I have the shutter speed, and winding knob attached to the housing for testing and cycling thru it to see where I can feel any resistance).
See I was under the impression (least when I got the mercury) that given it's unique design that it would be quite accurate even at 1/1000th which was supposedly considered uncommon for cameras at the time. I could deal with 1/1,000 losing a stop, but would have wished 1/300th and lower held at least within a third of a stop.
It's still disassembled (though I have the shutter speed, and winding knob attached to the housing for testing and cycling thru it to see where I can feel any resistance).
See I was under the impression (least when I got the mercury) that given it's unique design that it would be quite accurate even at 1/1000th which was supposedly considered uncommon for cameras at the time. I could deal with 1/1,000 losing a stop, but would have wished 1/300th and lower held at least within a third of a stop.
kb244
Well-known
According to Richard, it's not possible for the higher speeds to be off by more than the lower speeds because of the way the shutter works. If the lower speeds are a third of a stop off, then the higher speeds would be a third of a stop off as well. Ergo the tester is incorrectly reading the speed as the slit gets tighter.
It would explain why below a certain speed, they were all consistently off and at higher speeds it gets weird. Which on a focal plane shutter I would blame it being a different mechanism handled for slower and higher speeds, but that wouldn't be the case with the Mercury II.
So if the cleaning/greasing gets the low speeds up to spec, then I can assume that the higher speeds will be as well, pending an actual bracketed exposed roll test.
Thus far both Rick's diagrams, and Farlymac's step-by-step pictures have been very helpful in getting it apart without freaking out.
It would explain why below a certain speed, they were all consistently off and at higher speeds it gets weird. Which on a focal plane shutter I would blame it being a different mechanism handled for slower and higher speeds, but that wouldn't be the case with the Mercury II.
So if the cleaning/greasing gets the low speeds up to spec, then I can assume that the higher speeds will be as well, pending an actual bracketed exposed roll test.
Thus far both Rick's diagrams, and Farlymac's step-by-step pictures have been very helpful in getting it apart without freaking out.
Do the springs powering the disc lose tension with time? I have no idea whatsoever, because these are very pretty looking cameras, but outside my area of interest. If they do, it might conceivably explain the increased times, yes?
Cheers,
Brett
Cheers,
Brett
kb244
Well-known
Well got it all back together, with a little trial and error of some parts.
1) The replacement screw for the top of the control frame didn't work, it's too thick causing the housing not to go into the front of the camera completely. So if I want to find another screw for that I'll need to make sure it's a very flat profile.
2) Had a couple initial issues of the winding knob being too tight, turns out I need to hold off on tightening down the plate that goes over the frame counter gear, and to lube that a little bit. Since any extra winding friction is caused by that gear.
3) I removed the flash contacts and taped them together and set them aside somewhere safe, especially since one of the screws went bye-bye somewhere on the carpet. But I don't plan on using flash with it (It's bulb time sync'd anyways isn't it?, so I couldn't rig up a pc-sync adapter and fire off an electronic flash anyways)
4) All the speeds "test" about the same as before, but it's much cleaner and smoother feeling now. I just have to consider that 1/200 and up are just a third of a stop slower, since all the speeds below 1/200 are consistently that much slower, and that the tester just can't accurately capture above 1/125th.
Least now that it's been lubricated in the spindle areas, and oiled in others (general gear/spring area, and wiped up of any rust/etc that may have been present), along with some white lithium grease around the focusing helical, it should in theory remain relatively the same in performance during our winters outside.
That was a thought of mine, the speeds above 1/100th, might actually be off by only a third of a stop as well, my tester just might not be able to accurately test it (logically speaking, if one speed is off, they all should be off by the same, since the disc travels at the same pace for all the speeds, only the slit size changes).
If all the speeds are only off by a third of a stop over, then it could have come out of the factory that way.
A thought I had, but probably goes into the realm of "stop while you're ahead", was to wind the spring one more time past the stopping arm, so that it has a little more tension, but I have a feeling I could throw off the whole set of speeds doing that rather than only speeding them up by a third a stop.
Edit
Final Readings before I load it with film:
Tested 4x each speed, and already noticing how consistent it is from shot to shot at each speed. I also notice that all the speeds are consistently 1/3rd a stop over. (when you treat 1/1,000 as 1/500), I put the phototransistor/phone on a flat elevated surface so it doesn't move at all as I fire off the shutter (as opposed to hand holding it behind the shutter)
1/1000*= 1/380, 1/380.4, 1/380, 1/380.1,
1/300 = 1/212.8, 1/215, 1/211.9, 1/212.4
1/200 = 1/144.5, 1/147.9, 1/48.3, 1/145.3
1/100 = 1/90.3, 1/90.1, 1/90.2, 1/90.0
1/60 = 1/56.2, 1/56.5, 1/56.3, 1/56.7
1/40 = 1/37.7, 1/37.5, 1/37.8, 1/37.3
1/30 = 1/27.5, 1/27.7, 1/27.7, 1/27.8
1/20 = 1/17.5, 1/17.8, 1/17.4, 1/17.6
* Phototransistor not advertised to be capable of over 1/500 measurement, so the least amount of light it gets, it may detect as 1/500,
1/380-ish from 1/500 is roughly 1/3rd of a stop, so if 1/1,000th is being seen at best as 1/500, then this makes sense and falls in line with the rest of the speed deviations.
-Karl
1) The replacement screw for the top of the control frame didn't work, it's too thick causing the housing not to go into the front of the camera completely. So if I want to find another screw for that I'll need to make sure it's a very flat profile.
2) Had a couple initial issues of the winding knob being too tight, turns out I need to hold off on tightening down the plate that goes over the frame counter gear, and to lube that a little bit. Since any extra winding friction is caused by that gear.
3) I removed the flash contacts and taped them together and set them aside somewhere safe, especially since one of the screws went bye-bye somewhere on the carpet. But I don't plan on using flash with it (It's bulb time sync'd anyways isn't it?, so I couldn't rig up a pc-sync adapter and fire off an electronic flash anyways)
4) All the speeds "test" about the same as before, but it's much cleaner and smoother feeling now. I just have to consider that 1/200 and up are just a third of a stop slower, since all the speeds below 1/200 are consistently that much slower, and that the tester just can't accurately capture above 1/125th.
Least now that it's been lubricated in the spindle areas, and oiled in others (general gear/spring area, and wiped up of any rust/etc that may have been present), along with some white lithium grease around the focusing helical, it should in theory remain relatively the same in performance during our winters outside.
That was a thought of mine, the speeds above 1/100th, might actually be off by only a third of a stop as well, my tester just might not be able to accurately test it (logically speaking, if one speed is off, they all should be off by the same, since the disc travels at the same pace for all the speeds, only the slit size changes).
If all the speeds are only off by a third of a stop over, then it could have come out of the factory that way.
A thought I had, but probably goes into the realm of "stop while you're ahead", was to wind the spring one more time past the stopping arm, so that it has a little more tension, but I have a feeling I could throw off the whole set of speeds doing that rather than only speeding them up by a third a stop.
Edit
Final Readings before I load it with film:
Tested 4x each speed, and already noticing how consistent it is from shot to shot at each speed. I also notice that all the speeds are consistently 1/3rd a stop over. (when you treat 1/1,000 as 1/500), I put the phototransistor/phone on a flat elevated surface so it doesn't move at all as I fire off the shutter (as opposed to hand holding it behind the shutter)
1/1000*= 1/380, 1/380.4, 1/380, 1/380.1,
1/300 = 1/212.8, 1/215, 1/211.9, 1/212.4
1/200 = 1/144.5, 1/147.9, 1/48.3, 1/145.3
1/100 = 1/90.3, 1/90.1, 1/90.2, 1/90.0
1/60 = 1/56.2, 1/56.5, 1/56.3, 1/56.7
1/40 = 1/37.7, 1/37.5, 1/37.8, 1/37.3
1/30 = 1/27.5, 1/27.7, 1/27.7, 1/27.8
1/20 = 1/17.5, 1/17.8, 1/17.4, 1/17.6
* Phototransistor not advertised to be capable of over 1/500 measurement, so the least amount of light it gets, it may detect as 1/500,
1/380-ish from 1/500 is roughly 1/3rd of a stop, so if 1/1,000th is being seen at best as 1/500, then this makes sense and falls in line with the rest of the speed deviations.
-Karl