FHF 351

 
FHF 351

FHF 351

Description

One of the most popular caliber series of the FHF was the series 32, to which the caliber FHF 351 belongs, too. With a beating frequency of 21600 A/h, it is one of the most recent versions.

It has got a diameter of only 7 3/4 lignes (17.3mm), which it the same of all movements of that series and fits perfectly into small ladies’ watches.

base plate

base plate

Of course, all bearings contain rubies, even the minute wheel on the movement side. On the dial side however, the escape wheel has got a cap jewel on its bearing.

gear train

gear train

The gear train with its all silver colored gears is very classical: The mainspring barrel drives the center minute wheel, followed by third wheel, fourth wheel and escape wheel.

side view of the gear train

side view of the gear train

The FHF 351 uses a modern, screw-less, three-leg anular balance, which is of course shock protected by two Incabloc bearings. It beats semi-fast with 21600 A/h and uses a swiss pallet lever escapement.

FHF 351: Dial side

FHF 351: Dial side

The first thing, you’ll recognize on the dial side, is the pretty crude finish. Such slurred surfaces are normally only known from cheapest asia movements, and a indication, that this movement was released in a time, when the traditional watchmaking business was in big trouble because of the upcoming quarz watches.

Of course, the FHF 351 uses a yoke winding system, and the Incabloc shock protection was pretty standard that time, even on cheaper watches.

In the lab

The specimen shown here lacks the case, it most probably comes from a gold slaughter and certainly wasn't treated very carefully. It got a simple service and was adjusted on the timegrapher.

Timegrapher result

Hard to believe, what a good performance this tiny movement shows on the timegrapher. The low amplitude in vertical positions give an impression, how precise it tells the time, when it is in good condition. I’d see the rates within the chronometer range then.

horizontal positions
dial up 0 s/d 273° 0.3ms
dial down +4 s/d 287° 0.1ms
vertical positions
crown right (12 up) +5 s/d 228° 0.1ms
crown up (3 up) -7 s/d 218° 0.0ms
crown left (6 up) -13 s/d 219° 0.4ms
crown down (9 up) +1 s/d 232° 0.4ms

Technical data

Manufacturer:FHF
Caliber:351
Caliber base:FHF 32
Size:7 3/4''' (measured: 17,3mm)
A/h:21600
Number of jewels:17
Escapement:Pallet lever
Balance types: Nickel anular balance (three legs)
Shock protection(s): Incabloc
Balance bearing / direction hairspring:Clockwise
Moveable stud:yes
Adjust mechanism:Hairspring key
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:3 hole(s)
References: Flume: K3 N1 -
Inventory number:20057

Usage gallery

anonymous ladies' watch  (case missing)

anonymous ladies' watch (case missing)

This movement is a kind donation from Philipp Porter. Thank you very much for your great support of the movement archive!