Lubrication and assembly of MST 372 shock system

[tonydagee]

Hi all,

any ideas please on the correct way to service this arrangement?The circular spring seats first and I assume deals with lateral shock?The retaining spring of the Jewell is I think rubbed in, there doesn’t appear to be an end stone and a chaton that could be separated…

Any help or advice much appreciated!

 

 

[AndyGSi]

How did is disassemble?

I've never worked on one of these before but from the parts list I'd presume they were held in by the clip.

[nickelsilver]

The hole jewel in the spiral spring drops in, convex side up. Oil the cap jewel (flat side, it needs cleaning in the pic). Set it in place, getting one of the tabs in the recess, with the other lined up with the opening. Press it down, gently, until you can rotate it 90 degrees. The springiness of the ears holds it in place. The hole jewel is quite small, so don't put too much on the cap jewel, which is quite large in comparison.

 

If the cap jewel setting is loose when installed, you might have to flex the tabs up a little bit. The caps are often different movement side and cock side, the hole jewels should be the same.

[Nucejoe]

 I always detach the balance complete from the cock, and do the rest as Nickelsilver explained above.

Advantages of detaching the balance, specially if impulse jewel is shellaced. 

1- Lets you inspect both sides of the hole jewel of the cock , clean and even peg the hole from underside of the hole jewel.

2- Keep the balance complete  out of harms way as you press down on ear.

3-You have a chance to soak the hairspring side of balance in cleaning fluid for minutes.

Be careful to keep the impulse jewel above the fluid level. 

4- Easy to check pivot ( worn , bent ,  etc)  & take pics for closer look under high magnification. 

Rgds