Category Archives: Shutters

A simple shutter.

The Kodak cameras I have talked about recently both have a Jr. counterpart. These Jr. versions used a much cheaper shutter to reduce the selling price. These are simple shutters, they tend to have two shutter speeds and bulb.

Now I keep mentioning Learn Camera Repair for good reason … understanding is, well as Sun Tsu says “If you know neither the enemy nor yourself, you will succumb in every battle.” As you go along in the courses you will have the ability to work on this type shutter.

This is a Kodak Bimat lens with a Dakon shutter.


Like you typical folder, the shutter/lens can be removed by taking off the retaining ring screw from back.

The Kodak Bimat is a three element lens. You can unscrew rear element and put it aside.

For the front focus element you have to remove the hex stop post … you might want to mark the position of the front to align when you screw it back on.

DSC00797Unscrew front cell

The front plate is held by two screws … then it pull off.




Unscrew middle element.


This plate is held by four screws … note that some are covered by levers. Before removing this, close down the aperture.

The shutter release lever is in a slot, so you will need to slide-tilt-pull the plate to get it out.


DSC00799Note that there are no escapements as this is a simple shutter with two speeds, B, and T … that are all controlled by a couple of levers.

The large metal retard weight on the bottom is used to smoothen out the movement of the leaf lever as it opens/closes the shutter.

The torsion spring on the right is the main spring.

DSC00800 Ok, here is a visual example of a shutter that has been flushed … yes it can, temporarily, free up gummed blades but as you can see it leaves all the crap sitting around ready to resettle on the blades again.

The aperture sits on top of the shutter blades … which is the first time I have seen this, as typically the shutter is on top.

Pull off aperture control arm … leafs are somewhat attached due to the burst hole that is punched in the diaphram blades to use as a pin. Be very careful not to pull the blades off this ring, as it will damage the metal. If you look carefully at this image you will see that the aperture hole is out of shape … which means one of the blades is not sitting properly. After I took off this ring I could see that the burst hole on one blade was squashed, so it no long fit into the hole properly. I had to peel back the metal around the burst hole (without breaking the metal) and then fit it back into the ring hole.

Just put the whole thing in an ultrasonic to clean it, so you don’t have to put pressure on the blades.


Pull out speed setting lever

(note, in this image I had cleaned up everything and put it back together)

Open shutter blades by pushing leaf post to right.

Now you can lift this out through the back with something tapered.


The blade operating ring has three studs … longest one is also the leaf post, and is on the bottom (which engages the leaf lever).





This plate three large dimples that are used to create a space between the back cover … note when putting it back together the big slot is at 10 oclock




So … diaphram control ring … then aperture blades … then the cover plate dimples down  (not shown).


Pronto, pronto … Prontor.

Ok, so I got a … with the bunch of folders from Goodwill.

This camera was really cheap … so this has now become a test subject … or should I say an experience building project. Since joining the Learn Camera Repair FaceBook group, I have worked further into the restorations that have have done, particularly the shutter … scientia potentia est … knowledge is power.

I tore down this shutter to individual components, cleaning them, and then tried to put it all back in WORKING order … well, it was a chore … appears I have taken this apart about five times.

What did I learn?

  1. Camera Repair tech’s deserve the money they charge.
  2. Read repair course lesson 7.
  3. You never have enough hands.

So lets take a look at a Gauthier based Prontor-S shutter.

Note: if the metal parts look nice and clean it is because I took these images after I cleaned it … and sorry about the different colour temp of light as I added an additional illumination but it is warm white.

Another Note: to really finish off the blades you should put a bit of Moly on them … Molybdenum Disulfide (MoS2) powder.

DSC00819First you need to get the front element ring cap thing off.

Set focus to infinity. Loosen the three tiny grub screws, then remove the ring. Mark the front elements position to the focus mark … or just collimate later.

Unscrew front element

Unscrew rear element.

DSC00820Turn half-head lock screw

Unscrew inner notched securing ring.

Take off cover plate.


Full off speed cam ring.



The printed speeds point to the shutter setting lever.





Take a real good look at the movement of the levers and also how the tension springs are located … I have a closeup image later in the program.

Setting/main lever on top … speeds escapement … delay timer escapement … release lever … bunch of other levers.


So lets go … take apart to reveal shutter blades … layered

aperture | shutter | everything else

DSC00823Flip over – turn the aperture dial to reveal the four screws … mark the position of the long one

Hold the bottom, and pivot out with the flash port at base and pull off



DSC00815Clean blades (those are my fingerprints before I  cleaned up the blades … I really should not be handling them that way) and other things

Note the orientation/position of the blades.

Flip over.


Remove little tension spring on the bottom, one end of it anchors to the shutter ring and the other to the long screw that was removed from the back.

At 1 o’clock you can see the leaf lever engaging the pin on the shutter ring. Remove the cover thing. You will need to disengage the leaf lever from the pin.

Flip over


Remove the five screws+washers

Now you can clean up the ring and other surfaces.

Put the ring back on and remember to attach the leaf lever.




To take off self timer escapement, note the positioning of the large spring and pop it off the left side. Underneath there is an arm that catches the escapement that you will have to release, then turn self timer lever to align the  curved cutout notch

To take off speed escapement you have to cock the shutter to reveal a black screw … the second screw is the tall one.

Off to the ultrasonic cleaner … and a tiny dab of watch oil on the pins afterwards.


You can take this entire part into a cleaning bath … or if you are really ambitious you can take it all apart. I have done it but I did not take any pictures of it … and I really do not want to do it again just to show you.

At this point you really want to take good look at how all the levers are positioned, how they move, and most importantly how the springs are anchored … draw a spring map of what you can see.

Some tips from the experience:

Go slow and start with the topmost items (you really don’t have a choice about that).

One by one take one item off (well sometimes one becomes many) and note any springs that come with it … look at where the spring would be anchored

The shutter cocking arm main lever has a loaded main spring, when you try to pull it off it will pop !!! It is revolved once, so remember to do that when you put it back. I lifted it, almost off the post, with the spring attached and revolved it once (while keeping the leaf lever out of the way). Note one end of the main spring is anchored on a brass slotted washer, the slotted part rests on the bottom. Repair course lesson 7 has a trick using a wire string which looks easier than what I did.

You can start putting everything back together … but if you really really really, and I mean really, want to take the aperture apart you can continue on.


Turn aperture ring to open it up.

On the cover plate mark it where the flash socket is in relation to it.

Remove the two screws.

Tip: temporarily put it the plate back on so you get used to its position … note that it sits without much movement if all the holes line up.

DSC00828Take of the plate

Now you will see the aperture blades … do not feel bad if you feel like running away at this point, cause it’s gonna get worse.

Flip it over and let the blades drop out as one whole unit.


Here it it semi unfolded.

Look at how the blades overlap, which looks like a nightmare … its not that bad.

Take a really close look at the position of the pins on the top and bottom … they are slightly different. You will need to know this when you put it back. This image is of the bottom … you can see a slight difference to the image above

Separate the blades and clean them


Two screws hold the aperture plate on and also the aperture lever. When you remove the two screws the lever behind will fall off from the rear.




Now putting the aperture blades back together is the reason why this is a #$%@ pain in the ass …. though the more you do it the easier it gets … by the time you have done this a hunderd times it should be easy.

I noticed that all the blades were not cut the same … I could not figure out why, and most importantly if they had a major affect if they where not put into a correct order. I just put them in whatever order and it appeared to have no affect.

One way is to use the cover plate. Flip it over to the side that the blades would contact. Put the blades in the holes but leave them hanging outward with a weight in the middle … I did not take an image of this, but this site has a picture of what I mean: Prontor aperture blade assembly Then start pushing the blades towards the center one by one making sure to overlap them.

Once they are centered you can then place the bottom section on top of it … make sure the pins of the blades appear stay in the holes. Put the screws back in but not completely tightened. Open and close the aperture to see if the blade pins have fit properly.

Well if you made this far … you are doing pretty good.

TKS … blades of glory.

Tosei Koki apparently made their own shutter for their cameras … the TKS. I have not found any information about repairing this type … so I just went for it, and now you get to know about it.

This shutter had a specific problem, when you cocked the shutter the leaf’s would open up then shut … well this poses a problem by exposing the film to light. Obviously something is not right … so I went deep deep deep undercover for this one.

It took me a while to figure out how the mechanisms are supposed to work … but I did figure it out after watching how all the parts moved and how correct it.

FYI: I later figured out that this is a Gauthier type shutter … hmm, Camera Repair Course?

First thing to do is to remove the shutter from body. Like most folding cameras the shutter is attached with a ring screw that can be accessed from the back. I find it easier to get the spanner wrench into the knotches by not having it completely folded closed.


Now the bellows will separate from the shutter.

Revolve the front and you will see the rear lens element and a large paper spacer thing.

Work the paper spacer/washer out without damaging it.


Not much to say about the back.

You can unscrew the rear element and clean it up.




DSC00765OK, now back to the front !!

There are some small grub screws that hold the focus ring to the first lens element … I could not budge them, so I worked around it.

Remove the focus ring stopping pin … pin vise, plastic tip pliers, or just wrap something around it to avoid tool marks.

Rotate lens slowly while lifting lightly … when lens releases mark its position as you will use that when you screw it back on.


Unscrew the middle lens element.





DSC00767Remove the focus stopping post.

Turn the locking dial until the flat end faces the inside

Rotate securing plate until you match the notches.



Noticed the speed cam.

Pull it off.






The mechanism at 7’oclock, stamped T.K., is the self timer.

Remove the long spring.

At top there is a brass arm that need to be pushed out of the way.

Position self timer priming arm curved notch.

With your three hands … convince it all to come out.

DSC00770 1The slow speed escapement is held on by two large round headed screws. The top-middle one can be accessed after cock the shutter to push some arms/gears out of the way.



DSC00748Here is a view of both components.

DSC00771 1






Mark the position of the flash sync port on the aluminum plate … this will help when putting the shutter back together.

Note the torsion spring that is held on by that screw.

This image shows what I figured out about the shutter problem … when the shutter is set, the blades would open then close. At the top you can see the setting arm and the leaf lever. The leaf lever was engaging the blade stud. This should not occur if the stud is in its left most position … in this case it was not. The torsion spring (at 5 o’clock) is the blade-operating-ring spring, this keeps the shutter blades from opening. I noted that it was slightly bent out of shape, but even correcting this the blades where not kept in the fully closed position. This meant there was resistance on the blades, which required me to get down there and clean up.

Remove the spring and the sync port parts.


The shutter cocking levers and things are almost all spring loaded.

Take a careful look at how the springs are positioned … you may even want to make a map.

Keep them together when removing them.

DSC00753There are three large headed screws.





Gently flip over and the shutter part will come out in your hand.

This was the first problem … the shutter blades were not moving freely without resistance.

These need to be cleaned … and try not to bend them.

Clean the surrounding metal it rides on.

DSC00755Unscrew the three screws with the metal washer underneath.

Clean up the ring that moves the blades.






I was not so bold as to take apart the 10 leaf aperture … good thing they were in good physical shape, clean, and moving freely.

When going backwards to put it together note any bent arms, springs, and things … make appropriate adjustments.

Now I leave it up to you !!!

I know this ain’t going to be pretty!


So I have a camera with a problem.

As you can see there is something wrong with the shutter blades … yeah.

This ain’t no simple blades popping out of the slot issue, this one I know is really broken.

Well time to take a look inside.

I was advised that getting to the shutter on a Nikon FM2 was not that difficult … there is a pretty good video on YouTube showing how to get the mirror box off.

Now I have to warn you that the images show some parts that were taken off already … I don’t tend to document in sequential order as I go …

Ok, lets start from the top.

DSC00713First, remove rewind knob using the typical method is used. Under it is a tension clip thin and a washer.

The shutter speed dial is secured with 3 screws. Remove and pull off.

Advance lever … first remove cover leatherette, then unscrew the cap. Remove the lever and be aware of the spring underneath.

Finally the top cover, it is held on by five screws, pull off top plate.

DSC00714Note that there are two plastic parts, one on each side of the prism that will fall off as they are only held on by the top cover.

For a mechanical camera, the FM2 has a complicated electronic light meter system … it actually has dual SPD photosensors, so there is a lot of wires. I decided to loosen some wires by desoldering some of them.

Remove the bottom plate. Three screws.

DSC00718I desoldered the black wire to battery terminal (blue wire), red and orange to winder contacts … loosen white wire from glue.

Now open the back door.

Remove the single black screw.

DSC00715OK, now the front of the camera.

The lens mount … four screws.




There is a metal ring underneath … note it’s orientation … then take it off.

DSC00716Now there are some things left … there is a plastic ring with string attached and an inner metal ring that is tapered – thin side down.

DSC00717You can pull those out and put the one with the string aside.

Now you can unscrew front plastic cover two screws … pass plastic ring through it.

Self timer lever … take off the leatherette. Remove screw and self timer lever.

OK getting close now. Remove front two leatherette patches.

There are five screws that hold the mirror box/prism on. Remove.

Annotation 2019-06-16 163208There are three screws on either side of the viewfinder port … and one below the shutter speed dial that has a spring (not the other screw).

OK, this is the hard part … peeling off the top and moving it aside. You will encounter some old sticky foam.


Now here is where the video (I noted at the beginning) ends.

The shutter housing and the gears can be remove just by taking off the two brass top screws … do a little wiggling and pull off shutter.

DSC00720The back side of the shutter housing plate is held on by a couple of screws.DSC00721Then slide off.





More layers, more screws.

Make note of the tiny springs that are attached to both of the shutter blade sets.


You can now remove both sets of shutters.


So here is the second curtain. One of the blades actually snapped the metal into two … well that is not something you repair, just replace.

Putting the camera back together was not all that difficult either.

This one is now relegated to the parts bin … just to wait for another FM2 or an FE2 to land in my lap.

Hmm, I just realized I didn’t even check if the light meter was working …

… every act has a closing curtain.

Shutter curtains … hmm. I like leaf shutters cause they are easy to restore. Focal plane shutters, well that is a different story.

Leaf shutter

Leaf shutters have blades (though sometimes there is only one) that opens and then closes to expose the film.

Easy peasy. Kinda like taking off the lens cap and then putting it back on.

When you encounter these that don’t work, it usually just takes a cleaning of the blades to get them back in working condition.

Sometime in 1883, a guy named Ottomar Anschütz invented the rouleau shutter in order to take high speed images, as the leaf shutter was not fast enough. This roller shutter became the focal plane shutter that we know today.

Horizontal focal plane shutter

One shutter opens and the other follows it … this is like have two lens caps, one you take off the lens with one hand and then with the other hand you put the other cap on.

The timing of the two creates a slit that passes in front of the film to expose it for x number of seconds. The early focal plane shutters were horizontally traveling … and eventually became vertical using metal blades that could move faster.

Each curtain is connected to two rollers, one to set the shutter and the other attached by ribbons that are pulled by a spring loaded roller when the shutter mechanism is released.

Leica started using rubberized cloth focal plane shutters to achieve higher speeds in their infamous Barnack cameras, this was very helpful for an interchangeable lens systems as it didn’t require every lens to have a shutter built into it. Now of course everybody else had to copy this.

Over time, problems appeared with cloth shutters on old Barnack type cameras … or in many old cameras that used rubberized cloth … the type of problem that I have encountered most commonly is a deteriorated rubber on the shutter curtain(s). The Minolta-35 is famous for it. Another is the glue holding the ribbons has let go of the cloth or from the rollers … then there is the issue of degraded rubber causing light to leak through …

In the image below,  it is one of the ribbon tapes (top left) that pull the second shutter curtain that has come off of the spring loaded roller.

s-l1600_1Here is the crooked shutter … telltale angled wrinkles. The top is leaning because the curtain ribbon tape is no longer pulling the curtain.

In my case the ribbon was torn just after the point where it was glued to the roller, so it needed to be replaced. So I would need to get inside this thing to replace it.

You might want to read over Rick Oleson’s doc on a Leica shutter repair first … just to give you an idea. You can even watch Nobbysparrow do a replacement.

DSC00680Now wait till you get a hold of a multi-bladed vertical focal plane shutter !!

That’s another story to tell …