I own an IWC Portugieser Perpetual Calendar IW503702, and I would greatly appreciate advice on the best way to store it during an upcoming one-and-a-half-month period of travel, while the watch remains safely at home.
I am currently considering two options:
1) Leaving the watch on a watch winder for the entire period
The winder is set to 600 TPD (the lowest available setting). However, in practice I observe that the power reserve gradually increases, suggesting that over time the watch may remain at or near full power reserve for extended periods, with the mainspring’s slipping bridle engaging repeatedly. I would like to avoid a situation where the movement remains continuously in this fully wound state for several weeks, if this is not optimal for long-term preservation.
2) Leaving the watch unwound / not on a watch winder, so that it stops during my absence
In this case, I would wind and reset the watch upon my return after approximately six weeks. My concern is whether leaving a perpetual calendar watch stopped for this duration, and then restarting and resetting it, is the preferable approach from a long-term care perspective.
As this is a perpetual calendar model, I would be very grateful for a recommendation on which of these two approaches is preferable for the movement’s longevity and reliability.
Thank you
