Filmwasters
Which Board? => Articles => Topic started by: cs1 on December 15, 2018, 09:55:57 PM
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Today I had the "pleasure" of disassembling my Zenza Bronica SQ-A because the mechanism that moves the mirror and the flap behind it to the upright position stopped working in the cold. Since there's nothing about disassembling the SQ-A on the net, I'll quickly write up a few hints. I'm no expert and this is very likely not "by the book" (I don't have a service/repair manual). But maybe it helps others to avoid mistakes that I made.
Tools:
- JIS screwdrivers sizes J000 and J00 (I wouldn't use phillips screwdrivers because they don't seem to fit properly),
- very thin but broad flathead screwdriver,
- spanner wrench (used for the multi exposure lever),
- a plastic spatula to remove the leatherette,
- contact cement to glue back two leatherette pieces.
Warnings:
- Do not unscrew anything anything at the back where the film back attaches unless you know exactly what you're doing! Many of the screws hold pieces inside the case in place (e. g. parts of the film back release mechanism). If you randomly unscrew them, things will fall into the case and mechanism. I know what I'm talking about, stupid me did it and it took me more than an hour to undo the damage.
- Whatever you do, make absolutely sure that you're using the correct size of your JIS screwdrivers. All screws seem to be made of quite a soft material and you will damage the head if you don't use the right size. Some of the screws on my copy of the Bronica were really tight. I'd recommend to place the properly sized screwdriver precisely and use a controlled but strong amount of pressure when unscrewing a screw so that the initial momentum is strong enough to losen the screw properly. Dripping some alcohol on the screw to remove residue of any glue is helpful as well.
- The screw of the multi exposure lever is very delicate. Be careful not to damage it when screwing it back on with the spanner wrench.
The disassembly:
- Remove the film back.
- Remove the lens (this can only be done if the shutter is cocked).
- Remove the viewfinder.
- Remove the battery and the battery lid (if that's possible on your copy).
- I'd recommend to remove the ground glass as well (please refer to the SQ-A's manual how to do this). The screen is very delicate and can be damaged easily.
- Normally the Bronica SQ-A will not fire its shutter without a film back. However, you can still fire the shutter by moving the multi exposure lever to the multi exposure position. If you cock the shutter now it'll fire. It'll even fire without a lens and without a battery (the mirror will simply be released).
- (Note: it's necessary to remove all pieces of leatherette of both sides and of the bottom because most of the screws are covered by leatherette. Luckily enough all pieces of leatherette except for the one where the film back release is and the corresponding piece on the other side can be re-attached without glue. The remaining glue still works if you clean the surface properly.)
- Start on the side with the speed dial. Remove all leatherettes. Try to pull up a corner with the spatula and carefully pull it off. Make sure not to let dirt get onto the glued on side. Caution: the bottom leatherette only detaches easily at the upper part. The lower part that wraps around the rounded part of the case is attached with very strong glue. You can try to only peel away the upper part which probably can be re-attached without additional glue (there're no screws for the side piece at the bottom of the camera). Remember to peel away the two small pieces of leatherette attached to the speed dial.
- Unscrew the speed dial. Make sure to observe how it is attached (make note of the little notch that corresponds to a whole on the camera side).
- Remove all screws. Caution: do not immediately remove the side piece now! In the socket for the cable release there's a pin on the inside which will fall into the inside of the camera if you simply remove the side. Turn the camera so that the side that you're going to remove points down. Now remove the side piece and make sure not to lose the pin in the cable release socket.
- Remove all leatherettes on the side with the advance lever. It's easier if you remove the crank by pulling the silver pin out at the thicker end. Push it back in after removing the crank so that you don't lose it. Don't forget to remove the leatherettes on the mirror lock-up lever and on the advance knob. All of the leatherettes can be re-attached without additional glue. All the things that I said about the bottom leatherette on the other side apply to the bottom leatherette of this side, too.
- Put the multi exposure lever into the multi exposure position. That way you can test the mechanism of the camera later without having to adjust the setting with pliers. Use a spanner wrench to remove the screw. Carefully observe how the lever is attached and make a note of it so that you can re-assemble it properly.
- Now remove the mirror lock-up lever. Caution: on my copy this crew was very hard to remove. Furthermore it's made from a very soft material. Make sure to use a screwdriver that fits really well. It's a very thin but broad flathead screwdriver. Use enough pressure if you're absolutely sure that the screwdriver fits properly and is properly placed on the screw. Make sure that there's no residue of the glue on the screw. (Removing this screw went utterly wrong on my copy. I had to cut a new slit into the screw's head. It was a very discomforting phase of the disassembly...) The lever is attached with quite a number of parts. Make sure to note how it's attached.
- Unscrew the advance knob.
- Remove all screws. You can now remove the side.
- Remove the leatherette of the bottom side.
- Remove all screws. Caution: do not immediately remove the bottom plate! There's a spring that's part of the battery chamber's opening mechanism. It can fall into the camera if you aren't careful. Turn the camera so that the bottom side points down and then remove the bottom piece. Make sure not to lose the spring and the little piece that it's attached to.
You can now access the left, right and bottom side of the camera.
Please not: I have no idea how to remove the front plate where the lens mounts. The four screws that hold it in place can be remove easily, however, I didn't manage to remove the shutter release button so I couldn't remove it. If anybody knows how to do remove it, please let me know (it's not enough to remove the snap ring and the screw at the bottom of the shutter release).
Re-assembly (it's basically disassembly in reverse except for the following):
- When attaching the sides, make sure to push the levers for the viewfinder release and the lens release into the upper position.
- Attach the side with the cable release socket and the battery chamber with the side facing down (so that neither the pin nor the spring fall into the case).
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Wise decision to use Japanese Industry Standard screwdrivers. They look just like Phillips heads but have no pointy end.
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Unfortunately, I learned today that the whole disassembly adventure didn't do anything useful. I suspect that there's some sort of oil on the mirror and film chamber flap mechanism that freezes below 0 °C (or at least loses viscosity so that everything gets stuck). Cleaning the mechanism didn't do anything. The camera works without any problems at room temperature but doesn't below zero. I could disassemble it again but the main problem is that I have no idea how to properly reach the mechanism of the mirror. It's not accessible from the sides as far as I can tell.
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And using spray anything is definitely not recommended...
Since it sticks in the cold... have you thought of taping a hand warmer on the side of the camera?
That's my go to trick for cameras that need a lot of power, I tape one to the grip (or at least I used to... I tend to not go out that much when it's really cold) :(
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Yes, I was a good boy and didn't spray anything. I used some alcohol here and there to clean some obvious parts. But that was it. Unless a former Bronica service person lets me in on the secret how to fix this, I'll have to stick to summer outings with the Bronica. A handwarmer might work but that seems like a lot of hassle. I'll use my Canon F-1 during the winter. It's a very reliable workhorse even in very cold environments if you believe what they say about that camera.