Watch Winder Restoration
Recently, I’ve was requested to repair a watch winder which the owner had attempted to do so himself but failed. My immediate thoughts were, to repair it and at the same time give an honest opinion about the winder.
The first thing I noticed when I opened the unit was the sheet metal that the manufacturer has placed on the reclined board. In my opinion, since this is where the motors are mounted, the reclined board is crucial in absorbing noise generated by the motor gears as it rotates. So why did they use this material which will somehow sustain or maybe reverberates on its own? I guess the manufacturer wants to have a stereo effect when both sides vibrate.
The second surprise was that the viewing window was made from clear mica instead of the usual acrylic (or Plexiglass) which was rather disappointing.
As you may already noticed, each rotor winds two watch simultaneously on a winding cup. The cups or bowls, whatever you call it, has the same glossy lacquer as the exterior. Incidentally, they are made from wood. The ultra-suede was a fine touch to make it luxurious.
Overall, the housing construction was good but I’m no wood expert and therefore can’t tell what kind of wood was used. The base and interior, I know, is made with MDF.
There are four screws that secure the base. Opening it up, I found that the owner has thrown away the gear-head of one motor assembly leaving just the motor itself. The chalk marks, I think, is some kind of signature of the person assembling the unit.
Placed directly on the battery compartment, I saw a tiny circuit board which has a flash PROM and interestingly, there was a socket for LEDs but the manufacturer didn’t have any on the unit. My guess is they wanted to save a few cents.
Replacing the motor assembly had to be done in pairs for this unit as both were totally DOA.
To release the winding cup from the motor, I had to peel open the watch slots compartment to access beneath the cups. There were two screws underneath holding the motor shaft. Once I’ve unscrewed the cups, removing the motor was a breeze.
By the way, the watch slots were also well lacquered.
Picture shows a close up of the interior.
Next thing I had to do was to desolder the motors and replace it with two new ones. I have three Mabuchi samples on hand, so two would go into this unit.
Plugging all wires into the connectors, it’s time for a test run. It runs smoothly with no noise.
So its time to re-assemble the unit and go for a “weighted test”.
I have a new problem now.
1) The new motors rotate at 8RPM but I’m not sure of the winding cycles.
2) The slide switch at the rear shows 3 settings: – Automatic, Long-run Automatic and Continuous.
The owner seems to have misplaced the manual. So I had to figure out the winding sequence and the TPD settings.
At Automatic, the unit turns CW for about 1.5 minutes and stops for about 5 minutes, then continues in a CCW direction for 1.5 minutes and stops for 5 minutes. With an 8rpm rotation, this gives about 2659tpd both ways in 24 hours. That is, about 1329.5tpd in each direction.
At Long-run Automatic, the unit turns for 30 minutes, the stops for 120 minutes before repeating in the CCW direction. This mode gives about 1152tpd in each the CW and CCW direction.
In the Continuous mode, the unit turns CW for 60 minutes, the stops for about 10 seconds then CCW for another 60 minutes and stops for 10 seconds. In a day, this mode provides in excess of 11,520tpd in both combined directions. Way too high.
I have to disable the “Continuous Mode” because it provides far too much TPD than the watch needs. De-soldering the wires was the quickest (and neatest) way.
The owner needs to know about this issue.
1) The construction of the housing was excellent and the glossy exterior makes it look expensive on the outside.
2) The inclined plane holding the motors/winding cups should be made from full MDF so that noises generated by the gears can easily be absorbed by it.
3) The lowest TPD provided by this unit is 720 turns per direction and the highest being 3600 in each direction, assuming the original motor was at 5rpm.
4) The watch slots on the winding cups are too small to fit large bands and buckles, so owners of PAM watches should stay away from this one.
5) The controller board has an LED output but no LEDs were provided to indicate the winding status.
6) The viewing window was made from clear mica sheet and not acrylic or glass which was a real let down. Mica sheet is the cheap, thin cover found on a shirt packaging box or at the confectionary.
7) The motors were cheap toy motors with a plastic gearbox that wouldn’t last a few months.
I wouldn’t recommend this model even to my closest friend.