
but many vintage watches could still be made water resistant to original specs. Ive got a 1972 Tissot T12 chrono that passed the pressure text after servicing. I actualy went scuba diving (accidently) with a late 60s Seamaster with not ill effects whatever. I agree that you should consider them non-water resistant as a principle and don't actively try to test their water resistance but there is no particular need to molly-coddle a well maintained vintage watch, particularly if it was designed to be water resistant.
Check that the case back is firmyl closed, replace the seals, and if you live in a hot and humid country, it will be ok.
Best,
Nicolas
