One-Press Wide 300 Ejection Cycle

One of the most requested features of any Instax Wide 300 mod has been to keep the stock ejection cycle, or “one-press” ejection. While may have accomplished it, there was always a need for extra circuitry and some advanced electronics skills.

Thanks to an amazing and highly skilled customer, Nathan Duncan, we now have a relatively easy DIY solution! Also please keep an eye on Nathan’s page, he is working on an epic Wide 300 mod. There’s leather involved… that’s all I will say.

On to this modification.

Figure A

See Figure A above. Circled in red are the screws you will need to remove so that this battery/motor cradle can be removed. Make sure to keep it in this orientation facing UP, or you will drop all the gears underneath. One of the gears will fall out, but it’s ok. It has a long post and will be easy to put back in place.

Figure B

Once removed, you will see all the gears and a switch with orange wires. In Figure B, circled in red are gears that can be removed and set to the side. We will be working in the area within the blue circle. This image already shows the modification made, but before this you will need to trim away plastic that is obstructing that large gear. Cutting a V into it with flush cutters or a razor blade is how I do it, but you can also use any more sophisticated cutting tools like a Dremel.

Once you have access to the gear, you will see a small channel in it. We need to elongate this channel counter-clockwise. The original length of the channel is approximately 4mm, so we will need to double that to start and make it 8mm. In my experience, not all cameras are the same so on some I have now taken it up to 9mm. Start at 8 and perform trial and error until you reach an ejection cycle that sounds good to your ears and doesn’t advance with impulse or a slight shaking of the camera.

Now to the wiring. If you have already done the previous mod method, you probably removed the orange wires as I instructed. Doh! Well, now that this is accessible it will be a good idea to solder some wires back to that switch. During this wiring, be sure to keep the gears upright. If desired, you can install/uninstall the motor/battery cradle as needed during testing to minimize risk of dropping all the gears. Worse case scenario, just follow the images to put the gears back in their proper place.

In Figure C below, these are the only wires needed from the front. The thin pink wire is no longer there, and should have been removed with the original mod. All you will need is the thin blue wire (ejection positive), thin black wire (ejection negative), and thick black wire (battery negative).

Figure C

Figure D below shows the final wiring configuration to achieve a one-press ejection cycle. From top, to bottom:
– Thick black wire (battery negative) goes to the motor negative.
– Thin black wire (ejection negative) goes to the motor positive, combined with one of the orange wires from the switch in Figure B above.
– Thin blue wire (ejection positive) goes to the battery positive along with the other orange wire from the switch in Figure B above.

Figure D

All that remains is to dress the wires as needed to prevent interference with the gears, and securely install the motor/battery cradle back in place. With some cameras, there will be some trimming required of the film lifter bar if it ends up resting too high and interferes with the image. This is 50/50 with the cameras I’ve modified so far.

Hope that has been very helpful. If you have any further questions or suggestions, do not hesitate to contact me!