The Panerai Radiomir

Although it doesn’t much look like the type we are now used to, there is a definite case for calling Panerai’s Radiomir one of the world’s first dive watches.

It may be missing familiar elements like a rotating bezel or helium escape valve, but seeing as it was built specifically for military frogmen in the 1930s and was known to have a water resistance of around 10 Atm., it is not an outrageous claim.

Today, more than 80-years later, the Radiomir is still one of the most popular lines from a manufacture that sits at horology’s top table; an incredible achievement considering their products have only been available commercially since 1993.

Below, we look at the history of the Panerai Radiomir, as well as the current collection.

The Panerai Radiomir: Origins

As with so many brands which are now household names, Panerai stemmed from humble beginnings.

Set up as a combined repair workshop, sales showroom and the city’s first watchmaking school, the company was founded in 1860 by Giovanni Panerai in the capital of Italy’s Tuscany region, Florence.

The modest concern became a family business soon after when Giovanni’s son, Leon Francesco joined the firm, and expanded once again around the turn of the century when Leon’s own son, Guido came along.

By that time, the premises had moved from its original location to the Palazzo Arcivescovile in Piazza San Giovanni, opposite the Duomo, and the Panerai store is still situated there today.

The name had changed too, from G. Panerai & Figlio to Orologeria Svizzwera, to reflect the fact that the men were now fabricating parts for watchmakers in Switzerland—as sure a sign of quality as this industry offers.

Guido Panerai had actually been head of a mechanical engineering company which built equipment for the Regia Marina, the Italian Navy. And it was his invention of a luminescent material to coat the hands and dials of the navy’s underwater depth gauges and compasses which would lead to the creation of Panerai’s biggest triumph to date.

In 1916, he filed the patent for a self-illuminating paste containing zinc sulphide, mesothorium and the era’s wonder constituent, radium.

The element, discovered in 1898 by Pierre and Marie Curie, was prized for its many ‘valuable’ properties. As well as being touted as a miraculous panacea, reported to cure everything from blindness to cancer, its strong, lasting glow saw it added to lipsticks, toothpaste, chocolate and even chicken feed, with the hope that hen’s eggs would somehow cook themselves.

But the radiance was especially beneficial to watchmakers, allowing

timepiece dials to be read in the darkest conditions, even underwater. That made it, in Guido’s eyes, perfect for his military customers and so, on the 23^rd March 1916, Panerai registered their trademark for their luminescent paint, and called it Radiomir.

The Panerai Radiomir: The Invention

As important as the advent of Radiomir was, Panerai was still lagging behind others as far as actually creating watches went.

This was especially evident in the interwar years, which saw Rolex busy transforming the entire image of the wristwatch with their Oyster case, the first usable waterproof housing.

Happily however, Rolex and Panerai were manufacturing partners and so, in the 1930s, when the Regia Marina came looking for a solid, tough and, most importantly, water resistant timepiece for their recently founded unit of undersea demolition specialists, or frogmen, the two houses were able to come together to meet the demand.

The First World War had witnessed Italy’s platoon of combat swimmers score a number of vital successes and now, with hostilities once again on the horizon, the Italian Navy formed the First Submariner Group Command. This special forces detachment would, among other missions, pilot SLCs (Siluro a Lavita Corsa). Basically a 23ft-long torpedo, with two seats on top for the frogmen and carrying a devastating 300kg explosive payload, these Maiali (known as ‘Pigs’ by the crew because of the difficulty in steering them) had a maximum speed of just four knots. Even so, they were shatteringly effective, launched from submarines on daring raids into occupied harbors and targeting enemy warships. Moreover, the commandoes guiding them were amongst the bravest of the brave, and it was for these men that the Navy required a dive watch.

The Panerai Radiomir: The First

In truth, the very first Radiomir watch, the ref. 2533, owed more to Rolex than Panerai.

It was the Swiss manufacture who provided both the movement; the Cal. 618—a hand wound pocket watch caliber made exclusively for them by Cortebert, as well as the case, expanding one of their Staybrite steel cushion-shaped Oyster cases from the standard 26mm up to an enormous 47mm. Rolex also welded wire lugs top and bottom to hold the strap, made long enough to fit over a diving suit.

The dial, however, was all Panerai. Taking minimalism to the extreme, the brand eschewed numerals in any form and instead simply cut elongated baton slits for the 3, 6 and 9 o’clock markers, a double baton at the 12 o’clock and small dots for the remainder. But of course, the presence of their own proprietary lume made the whole thing perfectly legible.

The ref. 2533 had everything the Navy needed, but there was still plenty of refining to do.

Rolex and Panerai would continue to work together up to and throughout the war, with the Swiss brand assembling all the watches and Panerai’s Italian office performing any necessary modifications for the military.

The follow-up reference, the ref. 3646, is the model which set in place many of the distinctive aspects we associate with the Radiomir today, most notably, the dial construction. The face now consisted of two discs, one on top of the other. The lower disc was coated with the luminescent Radiomir paint, while the upper was matte black with the indexes (now large batons, with Arabic numerals at the cardinal points) stenciled out so the lume shone through. Still very much in use today, this was the first example of Panerai’s famed sandwich dial technique.

The Radiomir Through The Years

The Radiomir got a major redesign in 1940 when, concerned about the relative flimsiness of the watch’s soldered lugs, Rolex produced new cases machined out of a single block of steel, lugs and all.

The watch proved itself more than capable throughout WWII and the two manufactures continued to collaborate successfully on into the 1950s. But it wasn’t to last.

Somehow, it came to Rolex’s attention that a large number of Radiomir models had ended up in the hands of German divers (Kampfschwimmers) during the war. No one is sure how it happened, as Rolex was not shy about its anti-Nazi stance despite its vulnerable location in the heart of Switzerland and had refused to supply the German army on principle. But in 1954, instructions came through from Geneva that Rolex cases and movements were not to be used for watches destined for any military forces whatsoever, effectively ending the partnership.

The directive coincided with an order to Panerai from the Egyptian Navy for an even larger version of the Radiomir, and so they were forced to modify their own underwater compass and depth gauge housing to do the job. The result was the enormous 60mm ref. GPF 2/56, the first from the brand to have a rotating bezel. It is known as the Egiziano Grosso, or the Big Egyptian.

Panerai (Finally) Goes Commercial

Panerai was still first choice for a number of international forces for many years. However, in 1972, with the death of the last family member to head the brand, Giuseppe, a new CEO was appointed. Dino Zei, a former Italian naval officer, took over and shut down the watchmaking branch entirely to devote all his resources to aerospace instruments and navy diving kit.

But, as the 1990s arrived, and with them a refreshed appetite among the public for not only mechanical watches but those with a real military story to them, the renamed Officine Panerai spotted a gap in the market.

For the first time in its history, the brand began selling their products to the general public.

The earliest offerings, the Luminor, Luminor Marina (each with their iconic crown guards) and the Mare Nostrum chronograph, were met with crashing apathy. No one had even heard of Panerai at this point, and the style of these new pieces was unorthodox to say the least.

It would take the patronage of Sylvester Stallone, who was instantly smitten with the Luminor (and would wear one conspicuously in his move Daylight) who saved the manufacture from an ignominious failure.

Panerai’s fortunes transformed overnight, gaining a cult-like following almost immediately, dubbed the Paneristi, and opened the floodgates for more and more creations to make it out of the barracks and into the stores.

A limited edition of the Radiomir appeared soon after, numbering just 60 pieces and cast in platinum. Arriving at the same time as the trend for oversize watches, the 47mm models proved highly popular.

Many others would follow, with a variety of case sizes and all powered by in-house movements. The Black Seal collection from 2004 was especially well-received, with a design harking back to the 1930s originals, and that was followed up in 2012 by the Radiomir 1940, a neat recreation of the ref. 3646.

Today, Panerai, and the Radiomir, are still hugely sought after and only getting more so each year. The Italian maison has retained many of the watch’s most striking elements—the huge numerals, the cushion-shaped case, the signature handset—and added a number of varieties.

You can take your pick now from the simplest two-handers, to time-and-date and GMT models. Each brings a wonderfully modern take on a vintage classic; the dive watch that beat them all.

— Featured Photo: BeckerTime’s Archive.