zOwie Omega Discussion Forum

: Could holding a cassette/tape
: eraser/demagnetizer to the case back do the
: trick, or is demagnetizing a watch more
: complicated than this?

Essentially, that is what they do to demagnetise a watch. But since that device itself is a big electromagnet, you have to know what you are doing to eliminate, not increase, the magnetism in the watch. Watch shops have specialized versions of that same basic principle device that take most of the guesswork out of getting it right.

: Does this happen often in watches?

No. Modern mechanicals are pretty well shielded. Few people are ever around a strong enough magnet or electromagentic field. And these days, hardly anybody (as a percentage of the population) wear mechanical watches anyway.

In the past, there were some mechanical watches made for the few people who worked in environments where magnetism might be a problem for a watch. The original 1957 OMEGA Railmaster, the ROLEX Oyster Milgauss and ROLEX Submariner Millgauss are good examples of those watches with above normal magnetic shielding. Typically, they had not only extra magnetic shields in the back, but also used dials that were 2-3 times thicker than normal for the extra protection.