Waltham Grade 220

Description

The small American pocket watch caliber Waltham Grade 220 with a diameter of 38.7mm (12s in American measurements) was produced in large numbers at the beginning of the 20th century.

The execution is of very high quality; the mainplate is fully perlage-finished at the factory, the bridges are richly decorated, and of course all important bearings are jeweled, with three of them on the train bridges with double-screwed chatons!

As is often the case with American movements, a negative yoke winding mechanism is used, in which the winding mechanism is located on the movement side, not the dial side.

The gear train is constructed as usual: Mainspring barrel, large central and directly driven minute wheel, third wheel, decentral seconds wheel at 6 o’clock, and escape wheel. The latter is gold-colored.

Typical of American movements are the two banking pins of the pallet lever escapement, which are eccentrically mounted and adjust the engagement depth of the pallets.

A bimetallic screw balance is used, which features a fine adjustment of the regulator index. The hairspring itself has a Breguet terminal curve, meaning the escapement section is equipped with the best possible design.

Since the winding mechanism is located on the movement side, as described above, the dial side is quite empty and tidy; only the two Phillips head screws of the banking pins really catch the eye.

Technical data

Usage gallery