Cleaning of Watch Parts

Mechanical watch movements require periodic cleaning. Cleaning can be done manually in cleaning benzine using brushes, or mechanically in special machines. To clean watch parts effectively and without damage, the correct method and chemical solution must be selected for each type of contamination.

Cleaning a watch movement with a simple brush is not very effective, which is why I primarily use an ultrasonic bath and a mechanical chemical cleaning machine for watch parts.

Before cleaning, the movement is removed from the case, and the hands and dial are taken off. It is recommended to store all cleaned parts under a glass dome.

Equipment

Elma Mechanical Chemical Cleaning Machine for Watch Parts

Elma watch parts cleaning machine for mechanized chemical cleaning. General view.

Method of Use:

Before starting the chemical cleaning process, the movement is completely disassembled. The mechanical cleaning unit has several jars, which should preferably be numbered. In addition to special chemical solutions, acetone, benzine, alcohol, or distilled water may be used depending on the type of contamination.

The parts are washed step by step, starting with solution No. 1 and so on. During operation, the basket containing the parts moves from container No. 1 to container No. 2, contaminating the liquid in it. All solutions must be replaced periodically. When solution No. 1 becomes contaminated, it is discarded and can be replaced with filtered solution No. 2, while solution No. 3 becomes solution No. 2. A fresh solution is then used as No. 3.

The usual washing time is about half a minute. After rinsing the parts in solution No. 1, the basket is removed from the liquid and, without taking it out of the jar, spun in the air at high speed for a short time. The basket is then immersed in solution No. 2, where the operation is repeated, and the same procedure follows in solution No. 3. Finally, the basket is placed in a heating chamber, where it rotates slowly for about one minute.

Tips:

Large watch components such as the main plate, bridges, barrel, etc., are placed at the bottom of the basket. It is very important to arrange them so that they do not overlap.

Small parts are placed in one of the recessed sections of the basket tray together with screws and click springs. The mainspring should not be passed through chemical solutions, as they may cause corrosion.

Since some types of shellac and coatings do not tolerate chemical solutions well, the pallet fork and balance should preferably be cleaned with tested solutions or benzine.

About Cleaning Solutions:

Cleaning agents purchased from specialized stores can usually be used for only a few dozen cycles. In addition, if a solution is not used for a long time, it deteriorates and must be renewed.

Cleaning benzine is not always perfectly pure and may leave streaks. There are highly purified types of benzine, such as medical-grade benzine, but they are more expensive.

Ultrasonic Bath Bandelin Sonorex Super RK 514

Bandelin Sonorex Super RK 514 ultrasonic cleaner for non-contact chemical cleaning of watch parts. General view.

Ultrasonic cleaning is more effective than all types of manual cleaning. In addition, ultrasonic treatment ensures gentle handling and prevents mechanical damage, such as scratches.