Sigma 65

 
Sigma 65

Sigma 65

Description

Identifying cylinder movements is often very complicated, since, when these movements were most popular, only a few of them were marked, probably, since there was no professional supply chain with spare parts.

Fortunately, this 11 ligne movement is an exception, since below its mainspring barrel bridge, it has got a hallmark, which lets it identify as a movement from the manufacturer Sigma (Pèry Watch Co.). Due to the marking “065” on the dial side, it itentifies as Sigma 65.

base place

base place

As common on these kind of movements, the cannon pinion cannot be safely removed, since the axle, which goes through it and acts as slipping clutch, sits very strong.

But even with an only partially tore down movement, you can see that with its 10 bearing rubies, it belongs to the better cylinder movements.

gear train

gear train

The gear train is the common one for a cylinder movement: The mainspring barrel drives the center minute wheel, followed by third wheel, fourth wheel and cylinder wheel. As usual the cylinder wheel is beared below an own cock.

side view of the gear train

side view of the gear train

The three leg anular balance with its steel cylinder is not yet shock protected. It beats with 18000 A/h, which can be roughly adjusted with the help of a long regulator arm.

Sigma_65: Dial side

Sigma_65: Dial side

On the dial side, you see the yoke winding system with a pusher at four o’clock. On the lower half, you see the block consisting of dial side balance wheel bearing and cylinder wheel bearing. Both bearings have to be matched optimally to ensure a proper functionality, probably this was easier outside the movement.

Technical data

Manufacturer:Sigma
Caliber:65
Number of jewels:10
Escapement:Cylinder
Balance types: Nickel anular balance
Shock protection(s): none
Balance bearing / direction hairspring:Counterclockwise
Moveable stud:no
Adjust mechanism:Long regulator arm
Construction:
  • cylinder wheel
  • third wheel, large driving wheel, center minute wheel
  • mainspring barrel
Winding mechanism:yoke winding system
Functions:hour, minute
A/h:18000
Size:11''' (measured: 25,0mm)
Inventory number:20016

Usage gallery

anonymous ladies' watch

anonymous ladies' watch

This movement and watch is a kind donation from Mario. Thank you very much for your great support!