still to be verified
In one line
Universal Genève's second-generation microrotor: the winding mass shrunk and dropped into the plane of the movement so the watch could be made flat. The Polerouter, though, did not launch with it.
Start here: not every Polerouter has a microrotor
Polerouter and microrotor are treated as one and the same thing. They are not, and the gap between them is eighteen months of history.
Spring 1955 — the watch is renamed Polerouter and gains the microrotor: calibre 215.
Around 1959-1960 — the 218 arrives, adding a ball bearing to the microrotor so that it winds better.
Which means the first-batch Polarouter, the one collectors chase precisely because it came first, is the one without the component the watch is famous for. The spelling on the dial is the quickest tell: Polarouter with an A, Polerouter with an E.
And a warning about the numbers: 218 is not a calibre, it is a family, and the suffix decides everything. The 218-2 has a date and runs at 18,000 vph; the 218-9 goes up to 21,600; there are 28-jewel versions and 17-jewel versions. When two spec sheets for the 218 disagree, they are almost always describing two different suffixes.
Out of a polar flight
On 15 November 1954 a Scandinavian Airlines DC-6 made the first commercial flight over the North Pole, Copenhagen to Los Angeles. Crews passed through the airline's own Arctic flying school and were issued a watch built to cope with the magnetic field at those latitudes. Universal Genève made it and Gérald Genta drew it — born in Geneva in May 1931, so twenty-three years old at the time. Eighteen years before the Royal Oak.
The microrotor came afterwards. Universal introduced the calibre 215 in the spring of 1955: 28 mm across, 4.1 mm tall, 18,000 vph and around 48 hours of power reserve, with the winding mass sunk into the plane of the movement instead of turning above it. The company registered the name Microtor, which is why the word appears on so many dials — it is a trademark, not a generic term.
The 218 is the development, and it fixes the weak point. A small mass has little inertia and therefore winds poorly, so anything that cuts friction shows up in the result: the 218 runs its microrotor on a ball bearing. Out of it came the calibres 68 and 69, which carried the family through to the end of the company.
Why it matters
It is one of the most rewarding ways into microrotor collecting: technically significant, wrapped in a recognisable Genta design, and still within reach on the vintage market next to other microrotors of the period.
Two things that rarely get mentioned
- They were not first, and it cost them. Hans Kocher, chief engineer at Buren, filed the Swiss microrotor patent in 1954 (CH329804). Universal filed its own on 27 May 1955, and it was not published until 30 June 1958 (CH329805). Buren won the case and Universal had to pay a royalty on every movement — the figure usually quoted is four Swiss francs a piece. Neither firm copied the other; this was simultaneous invention, which is what happens when half of Switzerland attacks the same problem at once.
- Microtor was a line of watches, not just a word on the dial. For a short period Universal sold its microrotor watches as a separate range, kept apart from the Polerouters running the bumper calibre 138. That is where the dials marked Microtor but not Polerouter come from: they are not strange hybrids or swapped dials, they belong to that line.
Technical data
| Type | Microrotor automatic (Microtor) |
|---|---|
| Family | 215 (1955) → 218 (c. 1959-60) → 68 and 69 |
| Frequency | 18,000 vph in the 218 and 218-2 · 21,600 in the 218-9 |
| Jewels | 28 in the -2 and -9 versions · 17-jewel variants exist |
| Diameter | 28 mm |
| Thickness | 4.1 mm |
| Power reserve | ~48 hours |
| Date | Yes on the -2 suffix references |
| Shock protection | Incabloc |
| New over the 215 | Ball bearing on the microrotor |
What a watchmaker looks at first
The microrotor, every time. It is the part that defines the calibre and the part that wears: a small mass, a great deal of spinning, sixty-odd years of service. The test is easy — wear it for a full day and see whether it is still wound by the evening — and the ugly symptom is vertical play. If the mass rubs or moves up and down, the arbor or the bearing is due for replacement.
The second point is that Universal Genève stopped making anything decades ago, so there is no factory spare to fall back on. Everything comes from donor movements, which puts a price on parts and narrows the list of people who can do the work. Before buying a cheap one to restore, ask what the restoration costs.
And check which suffix you actually have before arguing with anyone about frequency. A 218-9 runs at 21,600 vph and there is nothing wrong with it.
Watches that used it
- Polerouter — the series that made the microrotor famous
- Polerouter Date — the date references, calibre suffix -2
- Polerouter Sub — with a dive bezel under the crystal
- Polerouter Genève and Polerouter NS — the 1960s series
- Universal dress watches signed Microtor on the dial
The calibre that launched the microrotor in 1955 has a page of its own: calibre 215. And the family ended with the calibre 69.