Handling and Hygiene

Before any tool touches a movement, handling discipline is already doing work to protect it. Bare fingers deposit skin oils and salts onto polished steel and brass, and those deposits can promote corrosion or contaminate a freshly cleaned and lubricated surface; watchmakers habitually handle plates, wheels and screws with tweezers or clean cotton gloves or finger cots rather than bare fingers, and they avoid breathing or talking directly over an open movement, since even fine airborne droplets and dust can settle into open jewel holes and among the wheels.

Dust and airborne debris are treated with similar seriousness, because a movement is, in effect, a collection of fine bearings and meshing teeth that a single stray fibre or grain of grit can foul. Work is done over a clean, lint-free surface, movements are kept covered with a dust cover or glass dome whenever they are not being actively handled, and a bench is kept clear of unrelated materials that could shed fibres or particles, such as tissues or fabric, near open work.

Static electricity is a specific, less obvious hazard: a statically charged tool or surface can attract and fling extremely small parts, and can also disturb a hairspring's coils, which are light enough to respond to a static field. Anti-static mats, wrist straps and anti-magnetic or anti-static tweezers are used in professional settings for this reason, alongside general awareness of dry-air conditions (such as low-humidity winter environments) that make static problems worse.

Correct handling technique for individual parts follows directly from their fragility: a hairspring is handled only by its outer terminal or by the balance it is attached to, never gripped along its coils; a jewel is handled by its setting rather than the stone face where possible, to avoid finger oils on the bearing surface; screws are picked up by the head, never gripped at the thread, which can burr threads that are already extremely fine.

These habits may look like minor fastidiousness, but they compound directly into the outcome of a service: a movement cleaned meticulously and then handled carelessly during reassembly can end up more contaminated than one handled with care throughout, and this is one of the quieter reasons a professional watchmaker's service differs so much in outcome from casual home intervention, even when the same nominal steps are followed.