PUW 500
Description
In the 1930s, maybe around 1933, the german PUW launched their first 8 3/4 x 12 ligne caliber, known as caliber PUW 500.
Pretty soon, it got an overhaul on the setting lever spring and was offered as caliber PUW 500 neu (PUW 500 new) until the late 1950s.
base plate
The execution of this pallet lever movement is contemporarily well, it is a massive construction and all important bearings contain rubies.
gear train
Thanks to its tonneau shape, a large mainspring barrel could be used.
It drives the center minute wheel, followed by third wheel, seconds wheel (at 6 o’clock, suitable for a decentral seconds indication) and the escape wheel.
gear train bridge
On most versions, an own cock is used for the escape wheel bearing, but on the version shown here, the movement side escape wheel bearing is part of the gear train bridge.
inside the gear train bridge
To make it look better, a visual trick was used: For the escape wheel bearing, the gear train bridge was sawed out to such an extent that it gave the impression of a real, even screwed-on cock. Only upon closer inspection can one recognize this deception, and even the screw of the fake cock serves no function at all, serving purely as a visual aid.
side view of the gear train
Of course, on such an old movement, its screw balance is not yet shock protected. It beats contemporarily slow with 18,000 A/h and can be regulated with the help of a long regulator arm.
PUW 500: Dial side
On the dial side, you can clearly see the old setting lever spring, which is positioned high up and angled downwards at a steep angle.
The old PUW hallmark is also visible in the upper third.
In the lab
Timegrapher result
The tested specimen had many broken jewels, which led to a poor performance on the timegrapher.| horizontal positions | |||
|---|---|---|---|
| dial up | -52 s/d | 184° | 2.8ms |
| dial down | -22 s/d | 227° | 2.6ms |
| vertical positions | |||
| crown right (12 up) | -70 s/d | 190° | 2.1ms |
| crown up (3 up) | -113 s/d | 157° | 1.6ms |
| crown left (6 up) | +50 s/d | 139° | 4.5ms |
| crown down (9 up) | +130 s/d | 157° | 4.3ms |
Technical data
| Manufacturer: | PUW |
| Caliber: | 500 |
| Size: | 8 3/4 x 12''' (measured: 19,6 x 26,3mm) |
| A/h: | 18000 |
| Number of jewels: | 15 |
| Escapement: | Pallet lever |
| Balance types: | monometallic screw balance (two legs) |
| Shock protection(s): | none |
| Balance bearing / direction hairspring: | Clockwise |
| Moveable stud: | no |
| Adjust mechanism: | Long regulator arm |
| Construction: |
|
| Construction type: | solid construction |
| Winding mechanism: | yoke winding system |
| Setting lever spring: | 3 holes |
| Attachment of setting lever: | screwed |
| References: | Feilner: Bl. 14 555 Flume: 1942 S.38 319 524 Jacob: 1942 15 061 |
| Mentioning in literature (years): | 1950 |
| Inventory number: | 24013 |
Usage gallery
Ormo gents watch (marked on the movement)