Bifora 910/1A
Description
Bidlingmaier in Schwäbisch Gmünd in Germany was one of the first manufacturers of selfwinding wristwatches after WW II. The caliber Bifora 910/1 shown here was launched in 1964 and already belonged to the last but one series of selfwindig movements and shows clear sign of cost-cutting fabrication.
Video on YouTubeWith a diameter of 11 1/2 lignes this movement has got the “full” size, the base movement, the Bifora 91, only uses 9 3/4 lignes, the rest is used by the oscillating weight.
main plate
At the main plate, you can see two things: First, that this movement uses plenty of bearing jewels, including the minute wheel, and second, that it is a pillar construction, which was cheaper to produce.
Detail: Minute wheel cock
The minute wheel cock of course houses the minute wheel. On top of it, there’s the friction spring for the indirect center second.
gear train
The gear train is common for most Bifora movements with the indirectly driven cender second hand and the two leg annular balance, which beats slowly with 18000 A/h and is beared in two inhouse Bishock shock protection bearings.
side view of the gear train
The mainspring barrel with open top side is odd, but often seen on Bifora movements. Even more unusual is the fact, that all gears, including the mainspring barrel(!) are housed under one single plate. But it seems, that there exists a second version of this movement, where the mainspring barrel is located under an own bridge.
base movement without selfwinding mechanism
Without the selfwinding mechanism, the Bifora 910/1A would be more or less a Bifora 910/1 or even a Bifora 91/1.
selfwinding mechanism
The selfwindig mechanism with two ratchet wheel changers (at 6 and 7 o’clock) allows a bidirectional winding and decouples the oscillating weight on manual winding.
Detail ratchet wheel changer
The ratchet wheel changer is equipped with a kind of seesaw, which enables free spinning in one direction.
movement without oscillating weight
Not only the base movement, but also the selfwinding mechanism is equipped with lots of jewels.
inner side of the oscillating weight
The oscillating weight is axle beared.
Bifora 910/1A dial side
The dial side is identical to the Bifora 91. With a yoke winding system, this movements is one of the best Bifora movements, despite the pillar construction.
In the lab
Timegrapher result
crown right (12 up)
crown up (3 up)
crown left (6 up)
crown down (9 up)
dial up
dial down
| horizontal positions | |
|---|---|
| dial up | -30 s/d |
| dial down | +30 s/d |
| vertical positions | |
| crown right (12 up) | -105 s/d |
| crown up (3 up) | -120 s/d |
| crown left (6 up) | -140 s/d |
| crown down (9 up) | -? s/d |
Technical data
| Manufacturer: | Bifora |
| Caliber: | 910/1A |
| Caliber base: | Bifora 91 |
| Size: | 11 1/2''' (measured: 25,6mm) |
| Height: | 5,3mm |
| A/h: | 18000 |
| Number of jewels: | 23 |
| Escapement: | Pallet lever |
| Balance types: |
Nickel anular balance |
| Shock protection(s): |
Bidlingmaier (Bifora) |
| Balance bearing / direction hairspring: | Clockwise |
| Moveable stud: | yes |
| Adjust mechanism: | Hairspring key |
| Construction: |
|
| Construction type: | pillar construction |
| Winding mechanism: | yoke winding system |
| Setting lever spring: | 3 hole(s) |
| Features: |
|
| References: |
Flume: K3 207 |
| Production years: | 1964-1980 |
Usage gallery
Bifora mens' watch