I've just posted my SP8 build at https://youtu.be/K6esLtZtmhQ. I can't really call it "the coup perdu" clock as I went with the deadbeat design. This was an easy one to get going. Apologies for the poor quality video and pictures - my phone wouldn't focus very well.
A few notes:
- the arbors were tight in the frame until I drilled them out with a 1.7mm drill. It wouldn't work reliably until I did this.
- the motor has the opposite connections to the one described in the instructions. It might be useful to add a note saying that it should rotate clockwise when the shaft is viewed end on, so you can check this before soldering it all up.
- I used a plastic encapsulated reed switch. This is a little larger than the glass ones: 3mm square cross section, instead of 2mm circular. I modified the switch cover to allow for this. Without doing this, the switch stood proud of the surface it is mounted on, and the magnet could never get far enough away to turn it off. Also I used a 6mm magnet, as I had some of these already, and opened up the hole in the flipper to fit it.
- it might be nice to have levelling screws in the base. It doesn't make much difference to the time keeping, but it is easier to adjust using the Cuckoo Calibration App when it is level.
Thanks for posting the video and adding the notes.
Small hole sizes are hard to design. Every machine has different tolerances and hole sizes seem to be the most affected. It seems best to let them end up undersized so they can be drilled to fit. Most arbors only need to be drilled about 1cm into each end before opening up to a much larger opening.
I am still planning to finish a video on the motor and trigger switch assembly. I will add comments about the proper rotational direction. I should modify the reed switch holder to account for the larger plastic switch. It seems less fragile than the glass ones. Positioning the magnet was a balancing act in this design. The magnet needs to be low so the lever arm has enough leverage to pull away and shut off. However, the low position does not move as far away from the reed switch. A 6mm magnet is probably much stronger than the small magnets that come with the reed switches. I experimented with placing two magnets on the "back" side of the lever arm to gain some distance and still be strong enough to trigger the switch.
Leveling switches are a good idea.