Baumgartner 800

Description

The Baumgartner 800 is a Roskopf-type pin lever movement with 5 jewels, an indirectly driven center second and a balance with lookalike screw imitations. Unlike later pin lever movements of Baumgartner, a lot of attention was put onto the looks.

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This pin lever movement was released before 1950 and is a Roskopf construction. This means, that the minute wheel is driven only on the dial side, indirectly by a coupled gear on top of the mainspring barrel. This construction allows a large mainspring barrel (even covering the center of the movement and more) and a large second wheel, thus eliminating one transmission step.

The speciality of this movemen is its indirectly driven center second, which is connected by the outer gears of the third wheel with a transmission of almost one-to-one.

Pretty funny is the balance wheel, which should look like a screw balance (at the time, screw balances were an indicator of a “better” watch): The “screws” are nothing but half-circles on the outer side of the balance ring:

The technical use is zero, but its optical effect is great.

Much more useful is a detail on the bottom of the balance: The ellipse is made of a synthetic ruby. This guarantees best possible force transmission to the pin lever and lowest possible friction - for a pin lever movement.

You can spot the ruby balance bearing (top and bottom use two jewels each: One for the bearing and one for the cap) and the yoke winding system. This is all a good indicator of a “better” (and mostly older) pin lever movement.

On the dial side, there’s the yoke winding system and the bearing of the lever with a U-shaped cutout. This cutout allowes the adjustment of the depthing of the pin lever - typical for a Roskopf movement.

Lab details

The movement shown here was resinified, when it entered the lab. It got a full revision with cleaning, oiling and regulating.

Timegrapher result

In the laying positions, the Baumgartner 800 performs very well, but in the hanging positions, it loses any precision, which indicates a now well balanced balance - probably the ruby ellipse is the cause here.

Technical data

Usage gallery

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