Preparing an instax 210 to use as a camera back

This video shows the process of stripping down an Instax 210 so that it can be used as a camera back. I use the result to convert Polaroid cameras to instax wide.
This involves taking out the electronics, taking off the lens, modifying the cycle gear, and wiring it so it will eject one picture at a time.
Since the making of this video, I'm using a relay to control motor run-on. This means that the cycle gear does not need any modification, making it much easier to prepare this camera to use as a back. Instructions on my website.

[@JeromeBocconGibod]

Tank you for this tutorial, very helpful ! Have you found a solution with a relay so we don't have to drill the gear ?

[@hackaninstant]

Yes, the relay stops the motor quickly so the timing switch doesn't have to activate early. The relay type and wiring diagram are on my website under the instax conversion.

[@mikamo]

So how long did the slot need to be on the final gear in the end?

[@hackaninstant]

The slot needed to be lengthened by around 3-4mm. This method does work, but I'm looking into another method which uses a relay to short out the motor when powered off to reduce run-on.