UMF 24-32

Description

The UMF caliber 24-32 adds an indirectly driven center second hand to the base caliber UMF 24-30.

This zero-jewel pin lever movement with the standard diameter of 10 1/2 lignes was produced between 1963 and 1991 more than 100 million times over all versions.

In the old construction of 1973 (week 50), you can see, that this movement did not yet have a moveable hairspring stud, since that was released in 1975.

The stamped base plate (here from february 1987) of the high building pillar construction uses only drilled metal bearings, and, as you can see, they are not exactly centered, or the “decoration” of the base plate is shifted a bit.

All geares are located under the large three-quarter plate.

The construction of the gear train is the usual standard with mainspring barrel, center minute wheel, third wheel, seconds wheel at 6 o’clock and escape wheel.

The sub version “-32” uses a center seconds indication, which is indirectly driven by the double third wheel.

On the side view, you can see, how high this movement builds.

It uses a pin lever escapement (under an own cock, but with full height) and a three-leg anular balance with a simple metal bearing and no shock protection.

Hairspring stud and hairspring key are concentric and difficult to adjust seperately.

The probably most interesting detail on the dial side is the height-adjustable (as a screw) balance wheel bearing.

On the dial side, you can easily spot the differences between the old (pre 1975) construction and the newer one: On the old construction, the rocking bar winding mechanism is made of metal, on the newer one, it is made of plastic.

The UMF 24-32 uses a rocking bar winding mechanism with ratchet on the inner side of the base plate.

Technical data

Usage gallery

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