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How to replace a Novodiac spring without a tool?


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I've seen some genuine ETA 6497-1's that use Novodiac type springs instead of a standard Incabloc. There are special tools made for Novodiac springs for various ETA movements but there is no such a tool available for 6497.

So, I would like to know how difficult would it be to handle the replacement in absence of the tool?

How do you push it down simultaneously in 3 places so it can be rotated to enter under the lips?

What technique brings best results?

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It is possible to remove the Novodiac with a toothpick that has the point cut off, You oce the blunt end over the spring and apply slight pressure downward while turning. ...but you may have trouble replacing it with that technique because you won't be able to see it when it locks in place.  I wasn't able to do it without  damaging it. I would suggest you save yourself the grief and buy  KIF or Novodiac tool. I bought mine from J Borel when you could buy a single tool (they come on three sizes) but now you have to get the set.

KIF tools_J Borel

NOvodiac_KIF tools_O_FREI

Joe

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OFrei and Borel both offer tools for Novodiac springs, and a set of these comes with 3 sizes. Neither of the sizes list 6487 as a caliber that would specifically fit any of the tools from the set.

It would be great to know whether someone used one of these tools, presumably the largest size, successfully on 6497/6498.

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Clarifying: 

OFrei and Borel both offer tool sets for Kif Trior springs, and a set of these comes with 3 sizes. The first question for me would be whether these tools for Kif Trior would work OK with Novodiac springs, since the springs are not exactly the same. If the answer is yes this would probably solve this problem. Also, Horotec makes a couple of tools specifically for Novodiac springs, and specifically for some ETA calibers (2801, 2824, 2834, 2836, 2660, 2671, and 2688). Neither one list 6487 as a caliber that would fit any of these tools.

It would be great to know whether someone used any of these tools successfully on 6497/6498 Novodiac spring.

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