Making enamel dials at A. Lange & Söhne

First of all, the basic raw material, a special kind of glass, is reduced to microscopic fragments by rubbing and crushing in a mortar, so that it can then be sieved or applied wet with a brush.

Treatment of the Back

Counter-enamel is applied to the back of the dial. This is necessary to prevent distortion of the enamel on the dial side through excessive stresses.

Filling Interstices

Small interstices between letters and figures are filled using a fine brush.

Sieving

The fine enamel powder is spread evenly over the dial with a sieve. The piece is then fired briefly at a temperature of several hundred degrees in a special kiln. These steps may be repeated several times.

Enamel Dust

During sieving, the fine enamel dust is collected on a piece of aluminium foil.

Slow Cooling

After each firing, the dial is cooled slowly on a fireproof support. Only when the dial has been completely dried and cleaned can the sieving operation be repeated. This process takes several days.

Treatment of the Dial

On the finished black enamelled dial, the contour of the aperture for the tourbillon is carefully hollowed out and finished with a luxurious polished chamfer.