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ETA 735 mainspring ZF873

rogart63

By rogart63
in Watch Repairs Help & Advice

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rogart63 Distinguished Member

rogart63

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Not that i am stingy?  But wonder if it would make a big difference? I look at  Ranfft at ETA 735 and it says that i should have a mainsping with number ZF873 . 

I then google that and then i find that ETA 2390 has the same mainspring. Look at cousinsuk . They say 735  mainspring cost £12,95  and the mainspring for ETA 2390 cost  £8 . 2390 is a little longer but has the same other sizes.  Why  does  the 735 cost more then the 2390  .  When ranfft says they are the same  but cousinsuk have 2 different mainsprings. 

 

 

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jdm Distinguished Member

jdm

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I don't know if these MS are the same or different but I can tell you that spare part prices have little to with the part itself. They can depend by unfathomable reasons, can be stale hence cheap, or driven by demand or rarity, so very expensive. The thing one can do is decide if worth the price for the project a hand.

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rogart63 Distinguished Member

rogart63

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Wonder what the ZF873 means on Ranfft ? Is that a special code for mainspring . can't find anything about it on google. 

Manage to find a spare 2390 movement from a friend. Trying to install that MS and see what happens. As the should be the same. 

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