It was in a burst of innocent ignorance that I said OK to a member who asked if I'd be willing to give one of his favourite Submariners a service. "Sure, no probs mate, just send it down!" I said, and a day or so later a nice vintage Subbie arrived. I had a quick look, took down the model and serial numbers for my records and put it in the safe as I was still working on the Seiko. Anyway, I finished the Seiko a few days ago and set it aside to keep an eye on time keeping and do occasional chrono testing. That's when I decided to do some research on the movement in the 7928 and found out it was a Tudor 390. A Tudor 390! Apparently just the mention of the caliber is enough to make seasoned watchmakers go "Oh! What's that behind you?", and then when you turn back, POOF!. They've vanished as if they were never there. That's when I figured I'd got in over my head, some of the comments on the interwebs pointed to the problems with getting parts, problems with the COST of parts if you did get lucky, problems with the lack of information on the caliber etc etc etc etc. I couldn't actually find anyone who had a single nice thing to say about the poor 390. I thought long and hard about it, read up as much as I could, and as most of the information I could find suggested that I had just stepped on something that went "click............", I decided to consult "A Wise One". The Wise One (actually @Archer ) got back to me with some excellent support material, a good discussion on lubrication and servicing, and ominously, some wise words. His wise words did not quite fill my cup of confidence: "The Tudor 390 is widely known to be a problematic movement to service, even for trained watchmakers" "the best comparison I can see is the old Rolex Cal. 1030, and having done some of those if it's in any way similar, these are not for the faint of heart" "Knowing what not to take on is one of the most important things you can learn in this business..." So, a sensible adult, who happens to be an expert in this field, had given me a very good idea of what was ahead. Hmmmmmmm, what next? I PM'd the owner and gave him the good news, and like a man who has great trust in his proctologist, his response was, to quote: "If you can fix bombs and stuff this is a walk in the park.......seriously, I have faith in you mate, give it a go" And that's how we got to be where we are at the moment. You're all probably bored shiftless by now, so time for some pics.