confession: lower shock spring abuse

[gaber]

Happy Holidays everyone!

Nearing the finish line, servicing an AS 1803 movement, I decided to clean and oil the lower shock jewel.  Laziness (or ambition?) caused me to attempt this while keeping the date wheel installed.  Approaching the spring from an awkward angle with my tweezers, I squeezed, and the spring broke.  Am I to blame?  I think so.  I didn't know these were so delicate.

This will be an expensive mistake, I think, and I should take the chance to add a 2021 resolution to my list.  Cost of correct incabloc springs.  Seems I will need to buy a jeweling tool to push on the shock setting from the movement?  Probably cheaper to buy a whole donor movement...:)

Sad:

 

Edited December 30, 2020 by gaber
picture of setting, my own solution

[watchweasol]

Hi the listed articles below available from cousins uk   no more than £5  so not too bad a cost.

[Nucejoe]

All you need is a spring,  housing for jewel setting can be pushed out with a wooden stick( inner side of mainplate)  slide the spring in and lock it, replace ** , finally put the jewels back in.

4 hours ago, gaber said:

 Approaching the spring from an awkward angle with my tweezers, I squeezed, and the spring broke.  Am I to blame?  I think so.  I didn't know these were so delicate.

Sounds like you simulatanously squeeze both prongs of the lyre spring in tweezers, slide each prong into the groove one at a time.

Replace**,   Use a FLAT end staking punch to push the housing back in or any  flat surface metal stick would work as long as its diameter is larger than that of the housing.

[Klassiker]

I would buy a set of five of the spring you need. The packs cost 5.50 GBP. If you can steal one from a donor, that's even cheaper. Not sure if you have to move the setting to fit it though. In the past I've been able to do without.

Edited December 30, 2020 by Klassiker

[gaber]

 

58 minutes ago, Klassiker said:

I would buy a set of five of the spring you need.

According to ofrei.com incabloc 975.03 is the correct part for this movement, and I do see that Cousins carries it, but I might just buy a donor as it is not so expensive.

1 hour ago, Nucejoe said:

 housing for jewel setting can be pushed out with a wooden stick( inner side of mainplate)  slide the spring in and lock it, replace ** , finally put the jewels back in.

Thanks, Joe, I'll give this a try.  To clarify, are you saying that the stick is applied on the inner side, so that the housing comes out on the dial side?  If this is the case, I suppose it needs only to be pushed a bit out to access the groove to install the replacement spring.  Also, I assume the housing needs to be replaced very closely to its original depth, so as not to affect the end shake of the balance, correct?

[Nucejoe]

26 minutes ago, gaber said:

the stick is applied on the inner side, so that the housing comes out on the dial side?  If this is the case, I suppose it needs only to be pushed a bit out to access the groove to install the replacement spring.  Also, I assume the housing needs to be replaced very closely to its original depth, so as not to affect the end shake of the balance, correct?

You have correctly understood my broken English on all counts.

Yes the housing is to be pushed out as you say above and as much as you say, it poping out would not trigger world war three either.

You are very correct that you can move the jewel for correct end shake so far as the staff length is concerned( not to compensate for worn short pivot)  ideally you want the housing positioned  to cover the groove inside the hole in mainplate, so as to prevernt the lyre spring from sliding out of the groove.

Wooden stick so not to scartch the housing, flat end so not to bend concave the falt face of the housing. Push on the outer edge of the housing at multiple points, not the middle.

When the housing is inserted , it might sit flush level with the mainplate, or stand proud a little, in case it is to be pushed in deep in the hole, I use a punch of smaller diameter or stick and push on the rim of the housing only, so to avoid pushing on the spring.

I think you got the picture right and will have success.

Good luck.