I ask because it seems to me, that a quartz analog watch needs bo jewels-the movement sends a pulse (once per second), to a stepping motor, so no friction. The rest of the gear wheels move so slowly, that friction is not important.
In contrast, a spring powered mechanical watch has most of the gear train under tension, so jeweled bearings are needed to reduce the friction (although why a watch would “need” 32 jewels is beyond me).
According to what I read, a mechanical watch needs 8 jewels-all others are superfluous.
You’re right about those superfluous jewels in mechanical watches. This was a result of a sort of arms race in the timepiece world many years ago.
Watch manufacturers would add extra jewels so that they could advertise that their watches were more better, and they clearly must have been because they had more jewels than the competition. Kind of like the amps that go up to 11.
Jewels in mechanical watches reduce the overall friction in the mechanism, hopefully improving accuracy. It is not far fetched to imagine that varying friction further down the gear train might affect the beat of the balance wheel to some infintesimal degree.
Considering that a Swiss chronometer certificate means that the watch keeps time to -4/+6 seconds per day, that’s an error of around -.005%/+007%. That’s pretty tight tolerance for a mechanical device. They need every edge that they can get.
Quartz watches, on the other hand, march to an almost perfect beat that has no dependency on mechanical friction. Hence, you could make one with no jewels at all and it could easily be more accurate than the best Swiss mechanical movement.