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Oliver Friedman posted a message to the mailing list explaining how to repair an FR1's exposure counter, the only weak part of the camera.

FIXING THE EXPOSURE COUNTER PROBLEM OF THE YASHICA FR 1

A common problem with the Yashica FR 1 is that the exposure counter doesn't work any more. This is usually caused by a small sprocket-wheel, which is part of the gear drive of the counter, being broken. At least Yashica in Germany doesn't have that part on stock any more. There are probably no fitting sprocket-wheels one could find in watches or toys.

The sprocket-wheel is pierced onto one end of a thin brass rod, and if the wheel breaks it will fall off that rod sooner or later. This can cause further damage to the film advance transport mechanism.

I have fixed that problem 24 hrs ago and do not yet know how long the fix will last. But I'm quite confident :)

Cees de Groot helped me to figure out how to open up the camera, and he will probably put a picture on his web-site which I shot while the camera was open. Please have a look at this picture as I will repeatedly refer to that picture when mentioning parts and motional directions.

DISCLAIMER

Proceed with the following at your own risk! I will not be liable for any damage you cause!

I strongly recommend that you have a qualified camera service technician do the job!

However, if you want to do it yourself for any reason though:

OPENING UP THE CAMERA

ATTENTION: FOR GODS SAKE REMOVE THE BATTERY FIRST BEFORE YOU OPEN UP THE CAMERA!!! Otherwise you will probably cause a short circuit and your beloved camera will be gone forever!

Open up the camera back. Put a wood-stick having a diameter of app. 4mm into the film rewind stub. (1 inch = 25.4 mm) Such sticks are available for making wood dowels in home improvement centers. While you keep the film rewind stub from moving by means of the stick, turn the film rewind knob to the left. This will require some force, but DO NOT use the film rewind CRANK for that purpose, as it may bend or break! Unscrew the knob.

Unscrew the metal part which holds the ASA speed ring. (I don't know how to call that beast in English.) Professionals probably use a tool which is called a 'Spanner' for that purpose, but I managed to unscrew that part with an ordinary screwdriver without much effort or any damage.

Unscrew the small black screw.

These parts belong together. Put them into a 35mm film container and don't put any further parts into that particular container. This will help you to find the correct screw for a particular screw hole as soon as you will reassemble the camera. Keep the other parts separate the same way.

Pull off round the plate in the center of shutter control dial. It is glued to the knob by means of contact cement. I lifted it by poking a needle below it from the side where the adjustment mark is. Unscrew the screw you find below that plate and remove the parts. Put them into a separate container.

Uncrew the rim around the release button. It turns counterclockwise, like an ordinary screw. Unscrew the release button. Again, it turns counterclockwise. You are confronted with that damn kind of screw again you wish you had a spanner for in order to remove it. But it can be turned with an ordinary screw driver as well. Put all parts belonging to the release button and the film advance lever into a separate container.

Remove the two black screws to the left and right of the YASHICA logo at the front of the camera. Put them into a separate container.

SLOWLY AND VERY CAREFULLY lift off the top cover of the camera. Watch out: The direct X contact is connected to the printed circuit board by means of a wire. If you are looking at the front of the camera (where the lens is) you will see four solder joints in front of the film rewind unit. The X contact wire is soldered to the second pad from the right.

I suggest to desolder that wire from this pad now, as we will have to insert the battery for testing purposes later on, and the metal of the camera top could cause a short circuit if it touches the circuit board while we perform our tests. Use a 15 to 30 Watts soldering iron. If you have a temperature controlled soldering station, adjust it to 290 deg C (554 deg F).

The picture at Cees' web site shows what has happened. To the left you see the counter assy, and a blow up of a small white sprocket-wheel belonging to it. This wheel, which is made of (white) Polyamide (Nylon), is broken. Possibly it already fell off the brass bolt it was mounted to.

Carefully pull it out using tweezers. Don't bend anything within the camera in order to perform this!

Put it into a can and pour gasoline into that can until the part is covered with gasoline. I haven't tried ordinary gasoline used for driving cars, but the pure stuff one gets in pharmacies and drugstores for the purpose of cleaning fabrics. Move the wheel within the gasoline with your tweezers or shake the can for at least 15 minutes. This will dissolve the oil and grease covering the wheel. Even if you don't see such grease or oil, go ahead as even very small amounts can lead to a poor glue joint. DON'T heat up the gasoline, DON't smoke, etc.! You know why! If you don't, consult Alfed Hitchcock's movie 'The Birds' first!

Put the wheel onto a clean piece of paper and wait at least 30 minutes to be absolutely sure that all the gasoline has evaporated.

Using your tweezers put the wheel into a vise with the crack facing upward. Adjust the vise to just hold the wheel in that position. The vise must not put much pressure onto the wheel as we want the crack to remain as wide open as possible.

Apply a tiny amount of Cyanoacrylate glue (I used 'Power Glue' by Tusker, but most other brands should perform as good as well. BUT: the glue has to be fresh! It deteriorates if stored for a long time. Buy a fresh package for this camera repair, and don't buy it from a store which probably put it into the shelf 5 years ago) onto the crack of the wheel. Just enough to fill the crack, not more. Don't worry about glue running into the hole of the wheel, we'll drill a new hole anyway. But no glue must run onto the teeths of the wheel! The smaller the diameter of the glue's nozzle is the better.

Immediately turn the knob of the vise to close the crack. This is tricky as:

  • 1.: Cyanoacrylate's bonding properties are the better, the thinner the glue film is. In other words: the more pressure we apply.
  • But 2.: the plastics of the wheel are flexible and if we apply too much pressure onto the wheel, it will bend, leading to a broader gap again.

Thus, just apply as much pressure as needed in order to close the gap. The sooner you are finished with that operation the better; Cyanoacrylate hardens very fast! Better you perform a rehearsal before you actually apply the glue.

Done? Great!

Leave the wheel clamped in the vise for at least three hours. We want to have the glue to be totally cured, before we go ahead.

I measured the diameter of the rod the wheel was pierced onto: 1.6 millimeters. Now guess what the diameter of the hole within the wheel was! 1.5 millimeters. Of course, it will stay in place if pierced onto that rod... But it turned out that it will break as well!

Let's widen up that hole in order to put the least amount of stress on our glue bond, and to avoid that the wheel will break again. I used an ordinary drill bit, having a diameter of 1.6 millimeters, and made for drilling wood, plastics, and non-ferrous metal, for that purpose. I didn't use a power drill, as the heat caused by the high rotational speeds of power drills (friction!) leads to deforming the plastics. Instead I simply rotated the drill bit with my fingers. The drill bit has to be sharp for that purpose; buy a new one, they are cheap. You will probably be astonished that with a few rotations and not much force the bit bites its way through the plastics.

Very, very carefully push the wheel onto the brass rod. Have a look at the blow up on my picture: the chamfered side of the wheel has to point towards the exposure counter. Apply counter-pressure from the other end of the rod to avoid bending/deforming the filigrane assy. I used a second tweezer for that purpose.

In my case the black plastics screw, which turns the wheel, applied a huge amount of pressure onto the wheel. We don't need any pressure. All we need is the plastics screw biting into the teeth of the wheel, not more. Any pressure can lead to the wheel breaking again. If there is pressure, then loosen the two black screws which hold the rod assy. One of them is shown on the picture just above the rod's spiral spring. The other, smaller one is located to the left of that screw and is hidden. Just loosen the screws, don't dismount them!

Now assemble the advance lever and the release button, and insert the battery. Put the rod belonging to the release button into it's hole in order to be able to trigger the shutter.

DON'T TOUCH ANY PART OF THE CIRCUIT BOARD OR OF THE SEVERAL SWITCHES WITH YOUR TOOLS WHILE THE BATTERY IS LOADED!!! THIS WILL PROBABLY CAUSE A SHORT CIRCUIT AND WILL BE THE DEATH OF YOUR CAMERA!!!

SLOWLY and CAREFULLY turning the advance lever again and again watch the motion of the bolt and the sprocket-wheels.

Open up the camera's back by pulling the bolt which usually holds the film rewind crank. As soon as you open up the back, the small white sprocket-wheel at the left moves to the right and releases the counter wheel (the part with the numbers printed on it). As this counter wheel is mounted to a spring, it will reset to the 'S' position. If you close the camera's back, the sprocket-wheels return to their original position at the left.

Play this game until every part moves virtually without any effort. The parts shall fit, but there should be no pressure between them. Then tighten the screws. Apply a small amount of nail polish onto the heads of the screws using a toothpick in order to avoid that they can move due to vibration.

Apply a tiny amount of the grease watchmakers use onto the two sprocket wheels. I used a grease containing Teflon (tm by DuPont), but traditional stuff will be sufficient. Under no circumstances use ordinary household or car-greases. They will harden very soon and/or become liquid at quite low temperatures and wander through your camera! They can cause corrosion, and and, and. Just visit your local watch-repair shop and ask for a tiny bit of grease.

Remove the battery again to avoid short-circuits during assembly.

Reassemble the camera.

Load the battery and a film and have fun!

Regards,

Oliver


 
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