magnetism

[ramrod]

i've got a question about magnetisn in watch movements. if a watch movement is magnetized, is it most likely the hairspring assembly that is affected? the reason i ask is that i have a seiko 7s26-7020 diver that i suspect has been magnetized. it runs like a house afire! i have several used 7s26 movements coming to me in the mail, and i was gonna swap out the escape. i do not have a demagnetizer. i DO plan on getting one, but i wanted to try this fix to see if it would work.

actually now that i'm thinking about it, i might just swap in one of the movements that i'll be getting this week. but i will try swapping in a newer escape for now.

[jdm]

Despite what is often repeated like a mantra, do not count too much on magnetism to severely accelerate a modern Seiko movement. More likely an hairspring issue, however to tell more you would need to share timergrapher pictures here .

[oldhippy]

Any foreign body on or in the hairspring can cause irregular time in any watch movement, it isn't just magnetism. Invest in a  demagnetizer there not very expensive. This bit I've said many times on here (demagnetize the movement to repair first)  

[rogart63]

Just now done some tinkering with a 7S26 movement. It was running very good but didn't have a great amplitud? But couldn't get it to run better? So  sent it to the owner? That wore it for a day. He said it suddenly runs several minutes to fast. So took it back. Demagnitized it and it runs good for a few minutes and snowstorm and then runs good again. But all it needed was a little push on the hairspring between regulator and the movable stud . And it runs like a star? Wrong lift angle maybe. Should be 53 i think . 

They sure are tricky to adjust the Seiko movements? 

Edited July 18, 2016 by rogart63

[jdm]

14 minutes ago, rogart63 said:

Wrong lift angle maybe. Should be 53 i think .

No problem, in practice lift angle does not affect timegrapher readings.

[ramrod]

i guess it's the first thing i assume. i will get a demagnetizer. when i get the new movements i will switch out the balance to see if it works. this watch runs beautifully despite it's speed.

Edited July 19, 2016 by ramrod

[jdm]

6 hours ago, ramrod said:

i guess it's the first thing i assume. i will get a demagnetizer. when i get the new movements i will switch out the balance to see if it works. this watch runs beautifully despite it's speed.

In reality you can't know how it runs without looking to the timegrapher or equivalent application.