Hi there ! Here's a fix I just completed on a Yashica Half 17 Rapid
Background
I recently bought an old lot of cameras and I've been falling in love with the Half 17 Rapid for some reason. The lens seems better than the minister and it's got so many nice features for a small package. I wasn't familiar with the half frames so I decided to bring it back to life. Searched around, and seems the sticky shutter is quite common and during this rebuild you will understand why. I love that almost everything in this camera is mechanic with linear speed/aperture between 30 and 800 and 1.7 and 16!
I didn't take pictures of the teardown but I took pictures from the rebuild, so I guess in reverse that would be the proper teardown sequence.
Also it's my very first camera teardown and repair so pls. bear with me and the layman's terms.
The mechanism as I found it
At this point I had removed the top rings of the lens, and de-soldered the red and black wires of the photocell.
Immediately you can tell Japanese ingenuity and simplicity. Basically this is mostly the camera, self-contained in the lens!
These are the main components from the front. These are probably not the technical terms, feel free to correct my layman's language:
Why the shutter was stuck
The shutter is sandwiched in between two plates. The front plate holds the mechanisms shown above which are basically most of the trigger, timings and flash sync. The back plate holds the iris control/limiter or f-stop, and the shutter blades are sandwiched in between. By turning the iris control (not seen here but you will see in the rebuild pics), the shutter is forced to stop opening at a given setting. Maybe all early cameras worked this way and it's the origin of the term f-stop - please comment if you know more.
The blades rest on a brass plate, whilst the top plate is some kind of tin alloy, which seems to be coated with something that degraded over time, OR by some liquid used to try to un-stick the shutter. It may also be leftovers of some light lubricant coating, who knows. Comments welcome.
The Fix
I polished the brass and the allow plates with fine-grain car-paint rubbing compound used to remove light scratches. I figured it would leave a smoother finish than an aggressive metal polish compound like Brasso, etc. After that I washed both plates with dish soap and warm running water to make sure to remove all the rubbing compound that will find it's way everywhere, especially the iris control mechanism which I did not remove for this. Then I blow-dried both plates to make sure no water was left anywhere.
After that, I carefully cleaned every surface and the shutter blades with lighter fluid and a lens microfibre cloth. I also cut the deformed light seal and mended with some red putty used for crafts, for exterior use, which is very stable at wide temperature differences. It's the type of white putty you would use to stick paper or photo to a wall and then remove without damage, but for exterior use which is red.
The rebuild
Ok, so now I will post the rebuild steps, and some comments along the way...
Step 1: Shutter Blade Assembly
1a: Attach Shutter Lever and Spring
You need to re-attach the shutter lever in order to re-assemble the shutter blades.
NOTE: I made a mistake here which I later corrected. Note that the spring has a long leg and a shorter leg. The longer leg is the one that should lean agains the lens mount.
WARNING: Also, note that the black steel screws are VERY fragile, only tighten 1/16 of a turn after it stops! I actually broke this one and another black one which you will see a non-critical part I had to glue with resin. In this case I was lucky and I was able to remove the stub. You have been warned.
1b: Shutter Leaf Assembly Order
1c: Completed Shutter - Ready to Close
Here is the shutter assembly ready to be closed. Note the polished surfaces, the repaired and repositioned light seal, and most especially the position of the flash wire.
This is the back side showing the iris control / f-stop and clicker. Light coating of silicon grease on the clicker.
Step 2: Main Mechanism Reassembly
2a: Attach First Level Parts
Re-attach the first level parts as shown below. Namely: bulb lock ("B" pos), trigger reset arms and the flash contact. Take special care to place the nylon isolators in the flash contact shoe.
2b: Attach Rest of the Parts
This step is pretty straight forward. Install the flash sync arm first. Then the winding and trigger arm and the flash stop. Place the flywheel last and make sure you align the teeth in the position shown below. You will notice the black screw hitting the brass arm as shown. You will also note a small marker mark I made to remember where the flywheel is tangent to the lens mount. It's not as hard as it sounds as it can only go in this position or you will notice right away. One thing to note is the exact position of every spring, including the long and short arms of each one. The only spring that requires more than a few degrees of winding is the trigger arm spring (lower left) which you will need to wind about 270 degrees to make it fit.
Step 3: Reassemble the Lens
3a: Attach Spring to Self Timer Trigger Assembly
The spring goes in a very specific way, pls. take note of the exact position:
3b: Position the Trigger and Self Timer Assembly and Re-Attach Mechanism to Lens
Continued on a reply because of the 15 image limit....
Background
I recently bought an old lot of cameras and I've been falling in love with the Half 17 Rapid for some reason. The lens seems better than the minister and it's got so many nice features for a small package. I wasn't familiar with the half frames so I decided to bring it back to life. Searched around, and seems the sticky shutter is quite common and during this rebuild you will understand why. I love that almost everything in this camera is mechanic with linear speed/aperture between 30 and 800 and 1.7 and 16!
I didn't take pictures of the teardown but I took pictures from the rebuild, so I guess in reverse that would be the proper teardown sequence.
Also it's my very first camera teardown and repair so pls. bear with me and the layman's terms.
The mechanism as I found it
At this point I had removed the top rings of the lens, and de-soldered the red and black wires of the photocell.
Immediately you can tell Japanese ingenuity and simplicity. Basically this is mostly the camera, self-contained in the lens!
These are the main components from the front. These are probably not the technical terms, feel free to correct my layman's language:
Why the shutter was stuck
The shutter is sandwiched in between two plates. The front plate holds the mechanisms shown above which are basically most of the trigger, timings and flash sync. The back plate holds the iris control/limiter or f-stop, and the shutter blades are sandwiched in between. By turning the iris control (not seen here but you will see in the rebuild pics), the shutter is forced to stop opening at a given setting. Maybe all early cameras worked this way and it's the origin of the term f-stop - please comment if you know more.
The blades rest on a brass plate, whilst the top plate is some kind of tin alloy, which seems to be coated with something that degraded over time, OR by some liquid used to try to un-stick the shutter. It may also be leftovers of some light lubricant coating, who knows. Comments welcome.
The Fix
I polished the brass and the allow plates with fine-grain car-paint rubbing compound used to remove light scratches. I figured it would leave a smoother finish than an aggressive metal polish compound like Brasso, etc. After that I washed both plates with dish soap and warm running water to make sure to remove all the rubbing compound that will find it's way everywhere, especially the iris control mechanism which I did not remove for this. Then I blow-dried both plates to make sure no water was left anywhere.
After that, I carefully cleaned every surface and the shutter blades with lighter fluid and a lens microfibre cloth. I also cut the deformed light seal and mended with some red putty used for crafts, for exterior use, which is very stable at wide temperature differences. It's the type of white putty you would use to stick paper or photo to a wall and then remove without damage, but for exterior use which is red.
The rebuild
Ok, so now I will post the rebuild steps, and some comments along the way...
Step 1: Shutter Blade Assembly
1a: Attach Shutter Lever and Spring
You need to re-attach the shutter lever in order to re-assemble the shutter blades.
NOTE: I made a mistake here which I later corrected. Note that the spring has a long leg and a shorter leg. The longer leg is the one that should lean agains the lens mount.
WARNING: Also, note that the black steel screws are VERY fragile, only tighten 1/16 of a turn after it stops! I actually broke this one and another black one which you will see a non-critical part I had to glue with resin. In this case I was lucky and I was able to remove the stub. You have been warned.
1b: Shutter Leaf Assembly Order
1c: Completed Shutter - Ready to Close
Here is the shutter assembly ready to be closed. Note the polished surfaces, the repaired and repositioned light seal, and most especially the position of the flash wire.
This is the back side showing the iris control / f-stop and clicker. Light coating of silicon grease on the clicker.
Step 2: Main Mechanism Reassembly
2a: Attach First Level Parts
Re-attach the first level parts as shown below. Namely: bulb lock ("B" pos), trigger reset arms and the flash contact. Take special care to place the nylon isolators in the flash contact shoe.
2b: Attach Rest of the Parts
This step is pretty straight forward. Install the flash sync arm first. Then the winding and trigger arm and the flash stop. Place the flywheel last and make sure you align the teeth in the position shown below. You will notice the black screw hitting the brass arm as shown. You will also note a small marker mark I made to remember where the flywheel is tangent to the lens mount. It's not as hard as it sounds as it can only go in this position or you will notice right away. One thing to note is the exact position of every spring, including the long and short arms of each one. The only spring that requires more than a few degrees of winding is the trigger arm spring (lower left) which you will need to wind about 270 degrees to make it fit.
Step 3: Reassemble the Lens
3a: Attach Spring to Self Timer Trigger Assembly
The spring goes in a very specific way, pls. take note of the exact position:
3b: Position the Trigger and Self Timer Assembly and Re-Attach Mechanism to Lens
Continued on a reply because of the 15 image limit....
