Bifora 52/2

 
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Bifora 52/2

Description

Bifora’s range of 5 1/2 ligne tonneau movements was very limited: The caliber 51 debuted in 1964 and was four years later replaced by the Bifora 52. The latter got during its short production period of four years, a change on the mainspring barrel and became the one presented here, Bifora 55/2, the final caliber in this tiny size.

One can only speculate as to why it was already over in 1974, perhaps watches, which needed such tiny works were no longer in demand, and maybe, these movements were too expensive to produce compared to the perennial favorites Bifora 91.

Bifora 52/2: base plate

base plate

Quality-wise, this movement is very well made, all important bearings, including those of the minute wheel, contain rubies. Thanks to the both side ruby bearings of the minute wheel, this movement counts its 17 jewels even without any cap jewels.

Bifora 52/2: gear train

gear train

Characteristically for the gear train is the tiny triange, which third wheel, seconds wheel and escape wheel reseble. The first two ones are really small, the escape wheel large in comparison.

Bifora 52/2: side view of the gear train

side view of the gear train

The tiny size requires a multi-storey construction, in which the bearings of seconds and third wheel are located above the escape wheel.

The balance wheel is a golden tones, two leg anular balance, which is beared in two inhouse Bishock-shock protections, and which already beats with 21600 A/h.

Its frequency is adjusted with a very small regulator arm or directly at the hairspring key.

Of course, a swiss pallet lever escapement is used.

Bifora 52/2: Bifora 52/2: Dial side

Bifora 52/2: Dial side

The dial side also offers a very neat and tidy picture, and of course a yoke winding system is also used here.

In the lab

The specimen on the timegrapher got a simple service and showed afterwards really well results, which should be even better after a “real” service.
For a movement of this tiny size, pretty amazing!"

Timegrapher result



horizontal positions
dial up +-0 s/d 257° 0.2ms
dial down +1 s/d 279° 0.0ms
vertical positions
crown right (12 up) -2 s/d 251° 0.6ms
crown up (3 up) -17 s/d 241° 0.1ms
crown left (6 up) -15 s/d 229° 0.0ms
crown down (9 up) -7 s/d 231° 0.4ms

Technical data

Manufacturer:Bifora
Caliber:52/2
Caliber base:Bifora 52
Size:5 1/2 x 6 3/4''' (measured: 13,0 x 15,0mm)
A/h:21600
Number of jewels:17
Escapement:Pallet lever
Balance types: monometallic anular balance (two legs)
Shock protection(s): Bidlingmaier (Bifora)
Balance bearing / direction hairspring:Counterclockwise
Moveable stud:yes
Adjust mechanism:Short regulator arm
Construction:
  • lever
  • escape wheel, seconds wheel, third wheel, center minute wheel
  • mainspring barrel
Construction type:solid construction
Winding mechanism:yoke winding system
Setting lever spring:4 hole(s)
References: Flume: K3 77
Production years:1968-1974
Inventory number:22019

Usage gallery

Bifora 52/2: Bifora ladies' watch

Bifora ladies' watch

Bifora 52/2: Bifora ladies' watch

Bifora ladies' watch