movement rotors

[db1]

Hi,

i noticed most of the lower-end (cheap) movement rotors are fixed with a screw and no ball bearing,

while the higher-end movements (such as eta, and the "35" jewels sea-gull and etc), does have ball bearing on the rotor.

whats the difference?

could a non ball-bearing rotor be replaced with a ball-bearing rotor ? (e.g. on the cheap mvoements) or it is a complete mechanism?

any information is welcome

[freddy333]

Unless both rotors are fixed to their respective movement's auto-wind modules by way of the same screw & the size/shape of both rotors (including the gearing on their undersides) are exactly the same, no. If there is a problem with the auto-wind function, replace the movement (or watch). If not, like they say........if it ain't broke, don't fix it.

And for whatever it is worth, I think it is a mistake to automatically dismiss a POS (piece of s-h-i-t) movement just because it was made in Asia or does not have ball bearings in the rotor. Some of my best friends lack ball-bearings (or have POS movements in them). For example, I was able to adjust this non-ball-bearing rotor watch (which was described in a recent tip on demagnetizing) to within +/-1 secs/day, which is well within COSC specs (many ETAs (with ball-bearing rotors) cannot do that)

Similar case with this old friend (which was described in my 1st diy He valve post) -- POS movement timed not quite to +/-1 sec/day, but definitely within COSC specs & it has maintained that for several years of beater use (prior to my DRSD taking over that job a year ago)

In fact & I will probably get flamed for saying this, but I have had more problems with ETAs (with ball-bearing rotors) in reps than any other movement (though most of the problems can be sourced back to the fact that rep factories tend to use (unserviced) 2nd hand movements). The biggest problem with POS movements is getting parts for them.