Description
One of the first Osco-movements, which Osco, born in 1948, shortly after the end of WW II, launched, was the form movement Osco 42 with a size of 8 3/4 x 12 lignes.
A characteristical feature of this pillar-constructed movement is its single bridge construction, which bears all gears, starting with the mainspring barrel, and finishing with the escapement wheel.
Escapement wheel, fourth- and third wheel have get bearing jewels, 1948 this was an indicator for better movements.
The gear train has got a classical linear (one-storey) construction, at that time, this was standard. You can see, how much space was unused.
A speciality of the specimen shown here is the gold-toned Glucydur screw balance. It doesn’t neccessiarily fit the rather simple pillar construction and the lack of a shock protection. To find such a movement in running condition (more or less, as the timegrapher will tell later), is not easy.
The dial side mets the expectations - for the winding system, a rocking bar mechanism has to be sufficient, and the click is nothing but a simple wire spring. Somewhere costs had to be reduced in 1948.
In the lab
Timegrapher result
The visually very pleasing Glucydur screw balance deceives a bit about the bad timegrapher results. For fairness one must say, that the rates would have been much better after a real service. Without that, the specimen tell about long and hard use:The rates nearly showed the limits of the timegrapher and the movement cries for a service!
horizontal positions | |||
---|---|---|---|
dial up | +-450 s/d | 126° | 2.6ms |
dial down | +24 s/d | 230° | 0.6ms |
vertical positions | |||
crown right (12 up) | +250 s/d | 154° | 2.6ms |
crown up (3 up) | +600 s/d | 150° | 2.6ms |
crown left (6 up) | -400 s/d | 125° | 2.1ms |
crown down (9 up) | -550 s/d | 147° | 2.0ms |
Technical data
Manufacturer: | Osco |
Caliber: | 42 |
Size: | 8 3/4 x 12''' (measured: 19.9 x 26.4mm) |
A/h: | 18000 |
Number of jewels: | 15 |
Escapement: | Pallet lever |
Balance types: |
Glucydur screw balance |
Shock protection(s): |
none |
Balance bearing / direction hairspring: | Clockwise |
Moveable stud: | no |
Adjust mechanism: | Long regulator arm |
Construction: |
|
Construction type: | pillar construction |
Winding mechanism: | rocking bar winding system |
Setting lever spring: | 3 hole(s) |
Features: |
|
References: |
Flume: 1952 36 |
Inventory number: | 17003 |