Description
In the early 1960s, Felsa released their series of tiny, 7 3/4 ladies’ watch calibers, the caliber series 21600, to which the caliber Felsa 4122 shown here belongs. It has got a screw-less balance and beats already semi-fast with 21600 A/h.
The quality is good, as always on Felsa movements. Thanks an (only on the movement side) ruby beared minute wheel and a cap jewel for the escapement wheel bearing (also only on the movement side), it could be advertized with 17 jewels.
The Felsa 4122 uses the traditional gear train, consisting of mainspring barrel, center minute wheel, third wheel, decentral seconds wheel at 6 o’clock and the escapement wheel which is controlled by a swiss pallet lever.
On the specimen shown here, the prolonged seconds wheel was shortened in a crude way.
If there also exists a version without prolonged seconds wheel is not yet known.
The modern anular balance with three legs and without screws is not yet shock protected, but already works with 21600 A/h.
Only directly at the hairspring key, the effective length of the hairspring is adjusted.
The bevel on the edge (both on the dial and on the movement side) means that a little height can be saved on the already quite flat movement, which is only 2.9 mm, because at the time there was a great demand for particularly flat watches.
In the lab
Timegrapher result
Despite the small size and obviously not always good treatment (visible, among other things, in a slightly wobbly balance wheel and an amateurishly shortened seconds hand axle), the timegrapher rates are very decent, but at the same time show the potential that this movement would have in really good condition.horizontal positions | |||
---|---|---|---|
dial up | -30 s/d | 229° | 0.5ms |
dial down | -4 s/d | 224° | 0.2ms |
vertical positions | |||
crown right (12 up) | +1 s/d | 185° | 0.2ms |
crown up (3 up) | -11 s/d | 179° | 0.0ms |
crown left (6 up) | -5 s/d | 193° | 0.3ms |
crown down (9 up) | +30 s/d | 196° | 0.7ms |
Technical data
Manufacturer: | Felsa |
Caliber: | 4122 |
Caliber base: | Felsa 4020 |
Size: | 7 3/4''' (measured: 17,25mm) |
Height: | 2,9mm |
A/h: | 21600 |
lift angle: | 52° |
Number of jewels: | 17 |
Escapement: | Pallet lever |
Balance types: |
monometallic anular balance (three legs) |
Shock protection(s): |
none |
Balance bearing / direction hairspring: | Clockwise |
Moveable stud: | no |
Adjust mechanism: | Hairspring key |
Construction: |
|
Construction type: | solid construction |
Winding mechanism: | yoke winding system |
Setting lever spring: | 2 hole(s) |
Attachment of setting lever: | screwed |
Features: |
|
References: |
Flume: K2 2 |
Inventory number: | 23062 |