My new FOIS, that I have worn maybe a dozen times, has developed an odd time-keeping problem: the last three or four times I have fully wound and set it (after not wearing it for a while), it will lose about four to five minutes within the first hour, and then if I re-set it after that, it runs close to accurately for the rest of the day. What could that be? It hasn't suffered any hard knocks or other abuse. I would guess if it were magnitized, it would be running fast. Any insights would be most appreciated.
I had a Hamilton that did that.... cannon pinion was loose. that's the thingy that allows the hands to slip so they can be set. once disturbed by setting it slipped a bit, allowing the hands to lag, losing time. once it grabbed again it was fine, keeping time well. once tightened up by my watchmaker it was fine..... or it could be the battery. then again, I fix motorbikes and robots, ask @Archer he fixes little things like watches and thermo nuclear devices.
You might be right, but still have it de magnetised before having it pulled apart. Wouldn't a loose pinion mean the hand/s wouldn't move? Or it could be that special FOIS battery
Depends on how loose it is I guess.... I've actually had it happen twice, both times the hands would "engage" 10 to 20 minutes after setting the time. I gather the pinion rotated till it hit a piece of dirt or rough spot and then dragged enough to move the hands. Both watches were on the high side of 100 years old and had a questionable service history so I can't say I was surprised at some strange action from them. Once cleaned and adjusted both were fine. One was Grand dad Olaf's 1905 Longines which he routinely "cleaned" himself by pulling the movement and soaking it in lamp oil. It would then sit on the porch in the sun for a day to "dry" the excess lubricant and be ready for service again. Actually.... its a miracle that the damn thing ever ran again but I've still got the watch and it currently keeps good time. On slightly more modern oils that is.
Your Omega needs the attention of a watchmaker who is familiar with Omega, and with chronographs. You say it is "new". Warranty?
