TPD. A short guide.
Turns Per Day. The single number behind every watch winder setting. A practical reading on what your automatic actually asks for.
Six things worth understanding.
What is TPD?
Turns Per Day. The number of rotations a watch winder completes around the watch in twenty-four hours. Different automatic movements need different TPD values to stay accurately wound without over-stressing the mainspring.
Why does direction matter?
Some movements wind in one direction only (clockwise or counter-clockwise). Others wind in both. The wrong direction will let a watch run down even on a high TPD setting.
How do I find the right setting?
Movement specifications are usually published by the manufacturer. As a starting point, most modern automatics fall between 650 and 1 200 TPD with bi-directional rotation. Use the table below as a reference and adjust to taste.
Can the wrong TPD damage my watch?
Excessive over-winding day after day can put unnecessary load on the mainspring and slip clutch. Robert Taylor cabinets use Mabuchi Silent System™ modules with conservative rest cycles to avoid continuous winding.
Does the cabinet adjust automatically?
No. TPD and direction are set per module — the cabinet does not change settings on its own. This is intentional: it lets a vintage and a modern automatic sit side by side, each on its own rhythm.
What if my watch isn't in your reference table?
Write to your Customer Success contact with the calibre name. We maintain an internal reference broader than the published table and will send the correct starting point.
Movement to TPD. At a glance.
A working reference for the most common automatic movements. Manufacturer specifications take precedence — adjust to suit.
Values are typical for the listed reference movement family. Robert Taylor cabinets are designed to accommodate a wide range of automatic mechanisms.
If you don't know where to begin.
Three sensible defaults based on the kind of movement you own.
- Modern automatic
650 – 1 200 TPD · Bi-directional
Covers the vast majority of contemporary calibres. Start here if you don't have manufacturer data to hand.
- Vintage / Manual
Manual wind only · Off
Manual-wind watches do not benefit from a winder. Let them rest until you wear them, then wind by hand.
- Complicated chronograph
Manufacturer spec only
Some chronograph movements have specific direction requirements. Use the calibre name to find published specifications before configuring.
Most TPD anxiety dissolves at 800 turns per day, bi-directional. Start there. Adjust toward your spec sheet from there.
Six terms defined.
- TPD
Turns Per Day.
Number of full rotations the cradle completes in 24 hours, counting both winding cycles and rest cycles.
- Direction
CW · CCW · Bi.
Clockwise, counter-clockwise, or bi-directional. Determined by the rotor design of your specific automatic movement.
- Rest cycle
Pause between sessions.
Robert Taylor modules wind for a short period, then rest. This avoids continuous load on the mainspring and slip clutch.
- Calibre
The movement reference.
Manufacturer code for the specific movement inside your watch — e.g. Rolex 3135, Omega 8500. The starting point for finding your TPD.
- Under-plate
Cabinet reference.
Each Robert Taylor cabinet carries an under-plate reference stamp. This is how Customer Success identifies the cabinet for service.
- Reference rig
The Mabuchi test bench.
The London bench's regulation test stand. Every cabinet is set against it before despatch.