Removing A Hairspring Stud

[DouglasSkinner]

I recently encountered a balance assembly in which the hairspring appears to be cemented into a grove in the stud.  (Actually, I have several watch movements of this type.)  There doesn't appear to be any way to unscrew the stud; nor is there any room to pry it off.  This is on an inexpensive EB movement.  How does one remove the hairspring from the balance cock in these cases?  Is a special tool required?

 

Thanks!

[bobm12]

I would venture the cemented portion can actually be removed using heat. It should be a red (dish) kind of color ... i.e. Shellac. But don't take my word for it, let's see what others opinions are...I may still learn something here by being corrected!

 

Cheers,

 

Bob

[clockboy]

The stud is a push fit and when you purchase a new hairspring they come with the stud fitted. A poor design but the EB,s I have worked on all had this set up.

[Geo]

Could you post a closeup picture to let folk see exactly what you're talking about please?

[Blacklab]

The stud is a push fit and when you purchase a new hairspring they come with the stud fitted. A poor design but the EB,s I have worked on all had this set up.

Just had the same problem on a Smiths TY, managed to remove the old one with a pair of needle pliers and tapped the new one in supported by rodico and a suitable anvil. Brutal but seems OK. Need to get a staking set really, but when I tell the boss how much they cost I am offered the choice of having my head tapped with a rolling pin or the frying pan.

[anilv]

Hi Lab,

The best time to bring up this subject is right after your partner has splurged on a new dress /kitchenware/kitchen etc.

Another good tactic is if you know people with bad (and expensive) habits...like drinking/drugs/crack (the drug, not the other type)... And compare this to your relatively harmless hobby. (This will obviously not work if you indulge in said bad and expensive habits yourself!).

Anil

[jnash]

ive actually re-cemented before on the 8420's