dcshooter
Member
Just picked up a fantastic Nikon F Apollo that is in great physical and mechanical shape except for one odd problem. The shutter speeds, both high and low, all seem reasonably accurate except for 1/8 sec, which is very slow, to my ear, it seems to behave exactly like the 1 sec setting. Oddly, 1/2, 1/4 and 1/15 seem to do just fine.
Is anyone familiar with this problem? Is it simply a tensioner issue, or perhaps a dirty escapement?
Is anyone familiar with this problem? Is it simply a tensioner issue, or perhaps a dirty escapement?
De_Corday
Eternal Student
I would not touch the tensioners. Those are, in my opinion, the option of last resort if a thorough cleaning doesn't bring it back to life.
I'm sure folks with more experience will weigh in, but were the camera mine, the first thing I would do is to flush the escapement with Naphtha
I'm sure folks with more experience will weigh in, but were the camera mine, the first thing I would do is to flush the escapement with Naphtha
_goodtimez
Well-known
Yes I would try to clean the escapement first. On the F I have done this with only removing the back and the base plate using a small syringe to poor in some Naphtha through the small hole underneath . I did this with the camera on its side, not upside down to prevent the Naphtha to drip onto the shutter curtains.
I have also removed the top right cover and applied a very tiny amount of watch oil to the gears up there.
I have also removed the top right cover and applied a very tiny amount of watch oil to the gears up there.
De_Corday
Eternal Student
This is an aside, but... Whats the harm in getting naphtha on Titanium foil shutter curtains? I once "cured" a jammed F3 in the field that way.
With most shutters the 1/8 second is usually the first slow speed to engage the star wheel pallet, so it does sound like an escapement fault. Although, escapements that are sticking usually tend to manifest more as speeds decrease, hence, it's most often the one second that stalls, not the 1/8, as the gear train has to be wound further for a second, to give the maximum delay, than it does for 1/8.
In your case, with 1s, 1/2, 1/4 etc. being OK, but the 1/8 running longer, I still suspect the escapement is the issue, but, it sounds a bit like the problem may be that the escapement control pins or levers (I don't speak fluent Nikon, sorry) are not being correctly set for the 1/8 speed. If, as has been suggested, you can see the escapement with the bottom cover removed, I would be inclined to get a light in there, work the speed dial through the speeds from 1/15 down to 1s, and see if you can visually detect the reason why the 1/8 is being delayed.
A few months ago, I had a similar problem with a Fujica ST801: all speeds good bar the 1/8 (which IIRC, was too fast in that instance, not too slow). It turned out one of the control levers that sets the escapement had become slightly bent (ST801 escapement lives under the bottom cover, so perhaps it was dropped, or banged onto a hard surface when it was set down at some stage?). Correcting the bent lever, which had jammed, saw the 1/8 come back in immediately. So I suspect yours should not be a very difficult problem to fix, if you can observe the escapement being set at the various speeds, and in operation, because, to my mind, it's sounding like a simple mechanical malfunction (Ie. worn, loose, distorted, or detached parts) may be the cause. I would certainly investigate that first, before contemplating any adjustments to the curtain tensions which will impact across the speed range. Keep us posted, please. I don't own a Nikon F, but, eventually, I would like to!
Cheers,
Brett
In your case, with 1s, 1/2, 1/4 etc. being OK, but the 1/8 running longer, I still suspect the escapement is the issue, but, it sounds a bit like the problem may be that the escapement control pins or levers (I don't speak fluent Nikon, sorry) are not being correctly set for the 1/8 speed. If, as has been suggested, you can see the escapement with the bottom cover removed, I would be inclined to get a light in there, work the speed dial through the speeds from 1/15 down to 1s, and see if you can visually detect the reason why the 1/8 is being delayed.
A few months ago, I had a similar problem with a Fujica ST801: all speeds good bar the 1/8 (which IIRC, was too fast in that instance, not too slow). It turned out one of the control levers that sets the escapement had become slightly bent (ST801 escapement lives under the bottom cover, so perhaps it was dropped, or banged onto a hard surface when it was set down at some stage?). Correcting the bent lever, which had jammed, saw the 1/8 come back in immediately. So I suspect yours should not be a very difficult problem to fix, if you can observe the escapement being set at the various speeds, and in operation, because, to my mind, it's sounding like a simple mechanical malfunction (Ie. worn, loose, distorted, or detached parts) may be the cause. I would certainly investigate that first, before contemplating any adjustments to the curtain tensions which will impact across the speed range. Keep us posted, please. I don't own a Nikon F, but, eventually, I would like to!
Cheers,
Brett
dcshooter
Member
Thanks guys! Your wealth of knowledge is on display as always.
I'll pull it apart when I get a spare couple of hours with some good light. All the pics online I've seen seem to indicate a fairly substantial disassembly - top, bottom plates, mount, and mirror box - to fully access the escapement on this one, and the service manual is not fully enlightening in this regard, so it might take some time.
The camera as received smells fairly strongly of "vintage" cigarette smoke (ah, the smell of the 70's!), so I am dreading opening it up and finding a layer of brown tar on everything.
I'll pull it apart when I get a spare couple of hours with some good light. All the pics online I've seen seem to indicate a fairly substantial disassembly - top, bottom plates, mount, and mirror box - to fully access the escapement on this one, and the service manual is not fully enlightening in this regard, so it might take some time.
The camera as received smells fairly strongly of "vintage" cigarette smoke (ah, the smell of the 70's!), so I am dreading opening it up and finding a layer of brown tar on everything.
dcshooter
Member
I found this Flickr Set by Wegothim who seems to have had a similar problem to mine. He ended up replacing the whole slow speed escapement assembly.
If I go that route, I suppose this is an option, although I am having a hard time believing it is actually NOS given how chewed up the screw heads appear in the photos.
If I go that route, I suppose this is an option, although I am having a hard time believing it is actually NOS given how chewed up the screw heads appear in the photos.
De_Corday
Eternal Student
Flush the mechanism first, before you replace. The F is a tank, and I'd be very surprised if somehow the control pallet got damaged. If it did, replacing the escapement won't help you.
I had the standoff prong on an f2 break off and flop around the mechanism, eventually getting jammed up in the film transport. Pulled it out and everything was good as new. Could very well be a broken internal, but these things are so tough that my money is on it simply being filthy.
I had the standoff prong on an f2 break off and flop around the mechanism, eventually getting jammed up in the film transport. Pulled it out and everything was good as new. Could very well be a broken internal, but these things are so tough that my money is on it simply being filthy.
_goodtimez
Well-known
Haha ! I am Wegothim on Flickr...
I fixed several Nikon F among the 40 units I own. I know this is crazy but I am crazy about the F
To reply to one of the questions: pouring Naphtha on the curtains has about no effect at all except leaving a small stain when it dries, however I prefer not to do it.
Check this out:
https://www.flickr.com/photos/8487951@N05/sets/72157637265450374/
https://www.flickr.com/photos/8487951@N05/sets/72157639898825694/
http://www.flickr.com/photos/8487951@N05/12382701853/
Flat Twin
Film Shooter
Hi there,
This is my experience...
Late last year I bought an Apollo with a very similar symptom as yours. I tried syringing naptha into the slow speed mechanism once I'd removed the bottom cover. The result was that it freed it up for about 5 minutes and then the problem was back and it was worse than before!! I tried it again and the problem persisted.
I sent the camera to Sover Wong of F2 fame and he serviced it for me and also replaced the slow speed escapement. The camera works perfectly now and after Sover's attention it it the smoothest and quietest F that I have ever owned. Well worth the trouble and expense...
By all means open your camera yourself, I hope that with the info provided by other members you can achieve a repair and I would genuinely like to know how you got on. Just be wary of my experience though, sometimes experts are needed!
Best of luck.
Regards
Simon
This is my experience...
Late last year I bought an Apollo with a very similar symptom as yours. I tried syringing naptha into the slow speed mechanism once I'd removed the bottom cover. The result was that it freed it up for about 5 minutes and then the problem was back and it was worse than before!! I tried it again and the problem persisted.
I sent the camera to Sover Wong of F2 fame and he serviced it for me and also replaced the slow speed escapement. The camera works perfectly now and after Sover's attention it it the smoothest and quietest F that I have ever owned. Well worth the trouble and expense...
By all means open your camera yourself, I hope that with the info provided by other members you can achieve a repair and I would genuinely like to know how you got on. Just be wary of my experience though, sometimes experts are needed!
Best of luck.
Regards
Simon
dcshooter
Member
Well, with the help of Goodtimes' photos and the scanned repair manual, I've gotten the escapement out. Nothing looks damaged or overly worn, and it doesn't appear to be very dirty, but it's going in the mineral spirits tonight and is being oiled tomorrow to see if that helps.
I wasn't happy about having to remove so much leatherette, since it was in factory-mint condition, but I managed to get it off without tearing it. Hopefully I can get it looking semi-decent when I put it back together. It's pressed between two pieces of glass right now, so hopefully it retains its original shape.
I wasn't happy about having to remove so much leatherette, since it was in factory-mint condition, but I managed to get it off without tearing it. Hopefully I can get it looking semi-decent when I put it back together. It's pressed between two pieces of glass right now, so hopefully it retains its original shape.
De_Corday
Eternal Student
re: the leatherette--get decent contact cement, it'll go right back like it was
dcshooter
Member
Well, I cleaned and lubed everything and stil lthe same problem. Looking more closely, I'm seeing that at 1/8 and 1/15, the changeover lever (part 306 in the manual) is not engaging the corresponding spring cam lever on the escapement that allows the star wheel brake lever to disengage (not sure of the names of these levers, since they aren't diagrammed in the service manual). However watching the changeover lever as I turn the shutter speed dial, it does appear that moving from 1/4 and 1/8, the lever moves forward as if to make engagement here. Between 1/8 and 1/15, the lever stays in the same position, then between 1/15th and1/30th, it pushes forward even further to fully disengage the brake and allow normal shutter speeds from 1/30th on.
Is this normal behavior?
Is this normal behavior?
That brake is the pallet. I will own an F one day but to date do not have any Nikons so can only offer general comments. Most shutters engage the pallet for speeds from 1/8 to 1s. The difference in times being how long the escapement is permitted to run. It's usually tensioned for its maximum run at one second and progressively shorter run off for less delay up to 1/15 at which point the pallet is disengaged. The pallet gives you that typical clockwork bzzzzz sound we are all familiar with. I would expect it should be engaging for 1/8. 1/8 should typically be set up similar to 1/4 but with Eg. slightly shorter lever throw for a shorter escapement run off. Sorry—not being familiar with the insides of an F I can't be more specific. Hopefully others will.
Cheers
Brett
Cheers
Brett
nobbylon
Veteran
I've had 2 F's and both went to Sover for treatment. They both funcioned as new. I would never pour or squirt lighter fluid or anything else for that matter into a camera! You have no way of controlling it's path etc. Whenever I've done slow speed mech's on Leicas I've taken them out to wash and lube.
Flat Twin
Film Shooter
As per my post further up, I agree with Nobbylon !^^^
Simon
Simon
dcshooter
Member
FIXED!
Turns out I was on the right track when I was noticing that the pallet engagement was off at 1/15 and 1/8. This could either have been caused by wear on the cam at the top of the camera at these positions, or excessive play at the changeover lever. I tried tightening down the changeover lever set screw to no effect, so I removed it and tried a new screw of the same size I was able to dig out of my parts jar. This one bites much better and has significantly reduced the play in the lever. Now when I switch to 1/8 or 1/15, it fully engages the pallet release lever (disengaging the pallet itself) and the shutter speed is correct.
As mentioned before, while I had the escapement out, I fully cleaned and lubed it, so now the entire shutter mechanism is running great (i lubed the top cams as well). Now to reassemble the mirror assembly and the top, and I should be good to go. No new escapement needed!
For the reference of anyone else encountering this problem in the future, the relevant parts in the service manual are #306 (lever) and #322 (screw).
Other useful information: For this body, the slow speed escapement is engaged at speeds 1 sec down to 1/30 and for bulb/T shooting. The pallet is engaged at speeds 1 sec down to 1/4. At 1/8 and 1/15, the palllet should be disengaged, as well as at B and T.
Turns out I was on the right track when I was noticing that the pallet engagement was off at 1/15 and 1/8. This could either have been caused by wear on the cam at the top of the camera at these positions, or excessive play at the changeover lever. I tried tightening down the changeover lever set screw to no effect, so I removed it and tried a new screw of the same size I was able to dig out of my parts jar. This one bites much better and has significantly reduced the play in the lever. Now when I switch to 1/8 or 1/15, it fully engages the pallet release lever (disengaging the pallet itself) and the shutter speed is correct.
As mentioned before, while I had the escapement out, I fully cleaned and lubed it, so now the entire shutter mechanism is running great (i lubed the top cams as well). Now to reassemble the mirror assembly and the top, and I should be good to go. No new escapement needed!
For the reference of anyone else encountering this problem in the future, the relevant parts in the service manual are #306 (lever) and #322 (screw).
Other useful information: For this body, the slow speed escapement is engaged at speeds 1 sec down to 1/30 and for bulb/T shooting. The pallet is engaged at speeds 1 sec down to 1/4. At 1/8 and 1/15, the palllet should be disengaged, as well as at B and T.
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Good effort. It's worth making the point for those who may not be aware, that the speed escapements used to mechanically control shutters often function in two ways depending on which speeds are being selected. With the pallet engaged you have a retard escapement. For intermediate speeds the pallet is disengaged, however the escapement continues to provide a delay function courtesy of the inertia of the gears, even if unbraked by the pallet. By designing a gear train with the appropriate number of gears of suitable mass, and incorporating a pallet control, one escapement can therefore be used to control a number of different speeds.
Cheers
Brett
Landshark
Well-known
It's not an uncommon problem. The fix is under the wind side top cover and is the adjustment used for it. The control is very finicky and usually if you can feel it turn that's way too much adjustment.
If you have more fun pulling the escapement first though..........
If you have more fun pulling the escapement first though..........
dcshooter
Member
Nope.
As stated above, in this case, the problem was not the adjustment at the top but rather excessive play in lever 306, which is on the upper side of the bottom of the camera and still would have required removal of the mirror box no matter what.
If you feel the need to make snarky comments without actually bothering to read the thread, though...