Novodiac is a shock absorber made by Incabloc. It is a Swiss made, removable anti-shock system found in a wide range of watches.
Incabloc currently dedicates most of their site to their lyre-spring style shock absorber, with almost no information about the Novodiac style.
In Incabloc’s own words:
“Novodiac is a geometrical alternative for a functional and economical spring system. Free, detachable spring. Bayonet-type attachment; no untimely unhooking. Novodiac is competitively price to meet your customers’ needs.”
Incabloc refers to Novodiac as a shock absorber for economical calibres. If a caliber comes in various grades (such as Sellita grades or ETA grades), Novodiac is typically found in the lower grades.
A complete Novodiac anti-shock system consists of several parts that are available in 3 sizes:
3 Prong spring
Cap jewel /end stones
Shock-absorbing lower block
Shock-absorbing upper block
Novodiac VS Etachoc:
You may have seen mentions of an an anti-shock device produced by ETA called Etachoc. Etachoc is basically the ETA (SWATCH Group) in-house produced version of the Incabloc Novodiac shock absorber. Novodiac springs can come in ETA packaging with a part number 289852. You can still find some of these on eBay and from some parts sellers.
Novodiac costs about half the price of Incabloc’s popular Double-Cone system. At the time of this post, a price for the complete upper setting with jewels and spring was found online for $8.00 USD. For just the shock spring, the price is around $2.50 USD.
Different Sizes of Novodiac:
Novodiac comes in different size options depending on the caliber it is being used in. The measurements are from the widest points. If you know the correct size of a specific caliber that you have worked on, please add it in the comments below.
231 – 1.7mm (some list as 1.65mm)
232 – 1.5mm (some list as 1.45mm)
240 – 1.25mm
How to remove Novodiac?
The three prong Novodiac spring is held in place at three points. Using a tool or other device, one must rotate the three prongs (sliding under the restraining tabs) until the three prongs reach the three openings in the setting. Be careful that it doesn’t fly away!