DuRoWe 55

Description

The form movement caliber DuRoWe 55 from Pforzheim, Germany, is noted in caliber lists as a 5 1/4 ligne movement, but that’s a bit off, since its real size is 5 2/3 x 8 2/3 lignes…

It is from the early 1950s and so has got the old, a little more long shape, which was replaced since the 1960s by more compact tonneau shaped movements.

Technically, it represents the state of the art of the 1950s and is well made. All important bearings contain rubies, so in total, this movement has got 15 jewels.

Other versions of this movement add two cap jewels for the escape wheel bearing and so, they can write “17 Rubis” on the dial.

The DuRoWe 55 uses the common gear train for these kind of form movements: Mainspring barrel, center minute wheel, tiny third and seconds wheels and a large escape wheel.

The lack of space leads to the detail, that the lower second wheel bearing is located above the escape wheel, so, here, we have got a two-storey construction.

The monometallic screw balance is not yet shock protected. It beats with 18000 A/h and can be adjusted at the hairspring key only.

As escapement, a swiss pallet lever is used.

On the dial side, you see the elaborate setting lever spring of the yoke winding system.

In the lab

Timegrapher result

Probably due to its age, this movement performs poor on the timegrapher. Only the very low beat error is very remarkable!