Impressed but not surprised

[acce1999]

Being the WIS I am, I always check accuracy when I get a new (for me) watch, and this time it is a Tudor 79090 from the very early 1990's. It has a Rolex specified ETA 2824-2 movement, expected to run within COSC and this one certainly do. Currently it is running within half a second per day. To be fair it speeds up a second or so one day, and slows down the next day. It is quite obvious how position and mainspring tension have an influence on the consistency, but since it constantly deviates equally on the plus and minus side from zero it is almost spot on at all times.

It is impressive to get this accuracy from a flat balance spring with a fairly simple solution for regulation. Interesting enough I have another equally accurate watch with a flat spring; my Explorer 14270 with it's caliber 3000. It has been running pretty much spot on since I got it in the mid 90's.

Both watches have recently been serviced so I expect many more accurate years from them.

Here they are, and I enjoy them very much:





Best,

A

[padi56]

Well Anders
IMHO the Breguet over coiled spring is more of a sign of the manufacturer's sticking to tradition and showman craftsmanship rather than a technical must have with todays modern movements.In the real world in terms of accuracy and reliability movements like the Cal 3000 and many others from say ETA with flat self-compensating hairspring are not inferior to the over coiled spring found in say the Cal 3135.Today the modern movements uses metals that are made from temperature compensating materials like Glucydur for the balance wheels,and in most Swiss watches for the last 4 decades Nivarox for the hairsprings including the over-coil ones, all very very anti magnetic materials,and mainly Nivaflex for the mainsprings .So today the need for other mechanical type compensator's are seldom needed in a well made mechanical movement.The ETA 2824 -2T and its clones is in its own right a fantastic well proved movement. And in its chronometer form is very hard to beat by any brand at any price for accuracy and longevity of life great pictures and watches.

[Dan Pierce]

Doesn't surprise me a bit, Anders as mine are well within COSC specs.
Gotta love that kind of accuracy.
dP