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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Longines A-7 Avigation Hack Watch
From: Bill Lionheart
Date: 2017 Sep 29, 21:36 +0100
From: Bill Lionheart
Date: 2017 Sep 29, 21:36 +0100
Hack was the term for something to do routine work, especially a horse, but my father born in 1927 would apply it anything such as a vehicle used for routine rather than special purposes. It was also used for a writer or journalist who similarly did routine work. So it is entirely consistent that a hack watch was just that, the watch for routine use while the chronometer was more special. Bill On 22 September 2017 at 19:43, Peter Montawrote: > In watchmaking I believe "hack" means to stop the balance (the > hairspring-and-wheel resonator that keeps time in mechanical watches) by > some external means. A watch with a hack feature might include a small > button on the case which, when pressed, would (gently!) force a braking pad > against the balance wheel, stopping it. Releasing the button and giving the > watch a flick (imparting some rotation to the balance to get it running > again) can start the watch with sub-second precision. Care must be taken > not to flick too hard to avoid damaging parts of the escapement. > > I don't know how the hack feature is implemented on a wristwatch when > pulling out the stem. Does the balance actually stop, or is the seconds > hand merely decoupled from the still-running train? > > It sounds to me like the navigational use of "hack" in "hack watch" is > unrelated. In particular, you probably don't want to hack a hack watch. > Hacking is crude---generally you want the watch to run continuously for best > performance. Chronometers would never be hacked, and even hacking a deck > watch strikes me as poor practice. > > Cheers, > Peter > > -- Professor of Applied Mathematics University of Manchester http://www.maths.manchester.ac.uk/bl