Movement Disassembly and Lubrication
Disassembling a mechanical clock movement for cleaning and re-oiling follows a predictable order: document the strike and chime levers, remove power from the mainspring or weight line, strip the dial side, then the back plate train. Brass American mantel movements — widely imported into Poland in the late nineteenth century — and European longcase calibres share the same plate-and-spacer architecture even when pillar shapes differ.
Power down and workspace
Before removing wheels, let down spring-driven trains with a let-down key in a controlled manner, or lower weight-driven lines onto soft cloth. A bench with a movement holder prevents plate flex when arbors are pressed out. In Polish workshops, winter static from dry heating air can attract brass dust; grounding the bench or using ionized air blowers is common practice described in open BHI technical notes.
Disassembly order
Work from the motion work outward: minute and hour wheels, then the centre wheel and escapement on the dial side, then back-plate wheels starting from the great wheel. Label each arbor position with tape flags or a photographed layout — reassembly errors at the strike levers cause silent hours or repeating strikes.
Inspection points at each arbor
- Pivot polish under magnification: scoring indicates worn holes or dried oil varnish.
- Pinion leaves: bent or closed leaves change depthing and produce uneven power.
- Plate holes: oval wear may require a new bushing rather than oil alone.
- Pallet stones: chips or improper lock cause recoil faults visible only after cleaning.
Published guidance from the Federation of the Swiss Watch Industry distinguishes watch-grade synthetic oils from thicker greases used on clock barrel arbors. Mixing grades — applying clock grease to a pallet jewel — can stop a small escapement entirely.
Cleaning
Movements are cleaned in solvent baths or ultrasonic tanks with clock-specific detergents, then dried completely before oiling. Wooden longcase movements with pinned frames require gentler handling; brass mantel plates tolerate standard aqueous cycles when pivots are not pressed into porous wood plates.
Oil placement
Oil belongs on pivot shoulders where rotating arbors pass through plates, on pallet impulse faces according to escapement type, and sparingly on the barrel arbor cap where manufacturer data specifies grease. Escape wheel teeth and pinion leaves run dry — oil there attracts dust and accelerates wear.
| Location | Typical lubricant class | Notes |
|---|---|---|
| Train pivot shoulders | High-viscosity clock oil | Small drop per pivot |
| Pallet jewels (lever escapement) | Watch-grade synthetic | Minimal quantity |
| Mainspring barrel arbor | Grease per calibre sheet | Not on the spring itself |
| Strike levers and cams | Dry or micro-oil only | Prevents dust adhesion |
Reassembly and testing
After reassembly, run the movement on a test stand without case cushions that might tilt the plates. Listen for rubbing at the warning wheel and confirm the strike count matches the hour selected on the rack. Only after strike and time trains run independently should the pendulum or balance be fitted for regulation.
