Hi Steve,
Firstly, congratulations on the new clock design. Looks great. I am about 25% of the way through printing all of the parts.
Now that I have seen how your are doing the Coup Perdu rewind, I cannot get out of trying to think how to "electrify" my 32 day pendulum clock. I was thinking about getting rid of gear 7 (Rachet), Gear 8 (Winding Drum) and Gear 9 and replacing this with you motor winding system. I was thinking about connecting the winding system to gear 4 printed with the 4 day option. Obviously the gears would have to be designed to properly mesh.
Do you think that the weight that is currently being used for the Coup Perdu clock would be sufficient to run the pendulum clock or would this have to be increased. If it would require an increase, do you think the N20 motor would have to be replaced with something bigger (something like Clayton Boyer's motor for the Swing time)??
How doable do you think this would be?
Cheers
Krys S
Great question.
The 32 day clock is a good starting point since the entire left side is dedicated to winding the clock. Gear 7 rotates the correct direction for a weight hanging off the left side.
The Coup Perdu hangs the drive weight on a gear with a 24 minute rotation. It rewinds every 3-4 minutes.
The 32 day clock has a 7 day mode with the ratchet slowed down by a 28 tooth gear driving the 38 tooth ratchet. This gives it an 81.4 minute rotation. Theoretically it would need 3.4 times as much drive weight. This is still a manageable amount of weight.
The Coup Perdu motor has a 20 tooth pinion. This could be reduced to an 8 or 12 tooth pinion to lessen the load on the motor.
Alternatively, are there other motors that might work:
Clayton Boyer's motor is physically a lot larger than the N20 motor. The no load current is about the same at 30mA. The loaded current is about double (80mA vs 40mA), but still within the safe range of the reed switch with a 500mA rating. It is a 12V motor that seems to require at least 5V to operate, so the clock would need 4 batteries.
This motor https://www.ebay.com/itm/322698617243 falls between Clayton Boyer's motor and the N20 motor. It is a good size. The current is only 15mA no load and 30mA loaded, so it is lower than the N20. It also needs at least 5V to operate. Total power would be about the same as using the N20. I am a bit concerned about availability. The N20 motors are really popular. This motor might only have one good source with limited supply. They get really expensive if you have to buy them new.
Steve