Notes kept while cleaning, adjusting and occasionally ruining old mechanical clocks. Written slowly, published rarely, indexed for nobody in particular.
Regulating a Vienna regulator that refuses to keep time
Bench log · pendulum, suspension spring, beat
Half the complaints that arrive as "it loses ten minutes a day" turn out to be a suspension spring with a hairline crack. The pendulum still swings, the clock still ticks, and the amplitude quietly collapses over an afternoon. Before touching the rating nut, hang the movement, listen for an even beat, and look at the spring against a bright window. A crack shows as a dark thread across the steel.
If the beat is uneven, the crutch is bent, not the escapement. Bend it in tiny increments with the pendulum removed, and check by ear rather than by eye. A clock in beat sounds like a metronome; a clock out of beat sounds like a limp.
Cleaning solutions and the myth of the ultrasonic bath
Bench log · cleaning, pivots, shellac
An ultrasonic bath removes dirt from places a brush will never reach, and it also removes shellac from pallet stones if the solution is warm and the cycle is long. Both facts are true at once, which is why timing matters more than chemistry. Three minutes in a mild ammoniated solution, a rinse, then alcohol, then air.
Pivots deserve separate attention. Dirt on a pivot is not really dirt but polished-in metal dust, and no bath dissolves it. Burnish it, measure it, and if the shoulder has worn into a step, accept that the bushing is next.
On buying broken clocks by post
Notes · sourcing, shipping, disappointment
Everything arrives with the pendulum still attached, swinging freely inside the case, having spent two days hammering the suspension. Ask the seller to remove it. They will forget. Ask anyway, because the request occasionally produces a photograph of the movement, and the photograph is worth more than the answer.
A case with water damage is a case, not a clock. A movement with a broken mainspring is a repair. A movement with a replaced platform escapement from an unrelated maker is a puzzle, and puzzles are what this bench is for.
Lubrication, in the smallest possible quantity
Bench log · oil, capillary action, patience
Oil belongs in the jewel or the oil sink and nowhere else. The usual failure is generosity: a drop that spreads along the arbor, collects dust, and turns into grinding paste within a year. Use a fine oiler, touch the sink, and stop when the surface tension pulls the oil into a bead.
Mainsprings take grease, not oil. Escapements take almost nothing. The strike train forgives more than the going train, which forgives nothing at all.