• See Also IWC Ingenieur

The Ingenieur SL (Called “Jumbo” and officially Ref. 1832 and 9232) was a major redesign to the IWC Ingenieur family in 1976.

Both Rolex and IWC saw the need for a watch for engineers and scientists in the 1950s, combining rugged automatic movements, water-resistant cases, and anti-magnetic concepts in the Rolex Milgauss and this IWC Ingenieur. The concept has remained for over 50 years, with the IWC Ingenieur family spawning many models, including an iconic redesign by famed designer Gerald Genta, a pivot to motor racing, and the use of exotic materials like titanium and ceramic.

The Ingenieur had become somewhat stale by the mid 1970s but famed designer Gerald Genta had shown a stylistic path forward with his groundbreaking Audemars Piguet Royal Oak in 1972. Genta designed three “SL” or “Steel Line” watches for IWC, of which only the Ingenieur was presented for sale. The production “Ingenieur SL”, introduced in 1976. Like the Royal Oak, Patek Philippe Nautilus, and Vacheron Constantin 222, the new Ingenieur SL had a “sandwich” case, with both the caseback and bezel being removable. But unlike those others, the Ingenieur used a novel approach The Bezel and crystal were screwed in place like a screwed caseback using five “bores” spaced around the circular bezel. This resembles the Royal Oak's screws but is significantly different technically.

The new case was much larger than previous watches, with an integrated bracelet and tonneau shape. Measuring 40 mm by 38 mm around a 30 mm dial, the “Jumbo” nickname seemed appropriate for the time. Some even called it “Fat” thanks to the 14 mm depth of the case.

The lumed sword hands remained, but the dial was updated with simpler bar markers on the hours and tiny bars on the minutes between. The dial gained a checkerboard guilloché pattern said to resemble graph paper. All models feature a date window at 3 00 and the “INGENIEUR” logo above 6 00 gained the initials “SL”.

The Ingenieur SL was available with both automatic and quartz movements but attracted few buyers. Just 978 examples of the model were sold between 1976 and 1984, never attracting the attention of the Royal Oak. This included 598 automatic models (532 Ref. 1832 and 55 Ref. 9232) and 380 quartz models (335 Ref. 3003 and 45 Ref. 9503). A thinner Ingenieur SL, Ref. 3303 was introduced in 1980 as a replacement, though the remaining Jumbo models languished in shops for a few more years.

The Ingenieur SL was again available with a steel or gold filled case as Ref. 1832 (automatic) or Ref. 3003 (quartz). A 18 karat yellow gold model with steel caseback was Ref. 9232 (automatic) or Ref. 9503 (quartz). All models came with a matching bracelet. The steel models were water resistant to 12 ATM while the gold models were only good to 6 ATM. Some examples were converted to quartz or automatic during production or after sale.

A "Skinny" Quartz Ingenieur SL, Ref. 3303 was introduced in 1980 to replace the quartz Ref. 3003. The Ref. 1832 Ingenieur SL Automatic remained on sale through 1985 but was not truly replaced until the 2005 introduction of the 42.5 mm Ref. 3227. Buyers looking for an automatic Ingenieur in the 1980s were instead steered to the 34 mm "Skinny" Ref. 3505 Ingenieur SL Automatic and its successors, which appeared alongside the “Jumbo” in 1983.

• 1976-1984: The «Jumbo» Ingenieur SL