Seiko 7025 Balence Spring

[Elton]

I,m looking for a spare 7025 balance spring. I was informed that the 7S26 one can be used.  Can someone reaffirm it is possible. 

[JohnR725]

11 hours ago, Elton said:

balance spring

I assume you want the balance complete not the balance spring?

I have a link below to your watch you can click on the part And then you get across reference listing which does look like the 7S26 is the same balance complete. Then just in case you really think you want the hairspring they're not considered replaceable components so you really want to get a balance complete.

http://cgi.julesborel.com/cgi-bin/matcgi2?ref=SEK_7025A

[jdm]

5 hours ago, JohnR725 said:

you really want to get a balance complete.

http://cgi.julesborel.com/cgi-bin/matcgi2?ref=SEK_7025A

At $14.50 plus shipping it may be more conveniente to get a complete SII NH35 for few dollars more, then resell, give away, or just play with the extra parts.

[Elton]

Thanks for the info. NH 35 is a good option if it is interchangeable. 

[Nucejoe]

On 2/5/2021 at 2:24 AM, Elton said:

I,m looking for a spare 7025 balance spring. I was informed that the 7S26 one can be used.  Can someone reaffirm it is possible. 

Hairsprings off of all members of seiko 7025 family/ generation are of same CGS (strength).

Dr ranfft's site lists such entire families, however, the length of hairspring (as well as its CGS) is a parameter in compatibilty of hairspring with balance wheel , not to mention that some modern collets are made to be non-removable( laser welded I think).

All this in practical terms mean,  if you safe keep all your damaged balance completes, you are very likely to have in your aresenal hairspring which will vibrate with a wheel in need of hairspring, yet even a H/S off of a 7025 might not vibrate with another 7025 wheel.

An experience repairman doesn't discard damaged balance completes.

Regs

Joe

 

 

[VWatchie]

On 2/5/2021 at 4:16 PM, jdm said:

At $14.50 plus shipping it may be more conveniente to get a complete SII NH35 for few dollars more

Cousins have it for £28.95 (Excl. tax and shipping). Haven't checked with eBay and others.