Help with Main Barrel Bushing/Jewel Replacement

[mzinski]

I have a UG218.2 with WAY too much sideshake in the main barrel. I have all ready replaced the arbor and will be moving on to dealing with the bushings. 

I'd like to try my hand at replacing the bushings with jewels. I'm going this route because 1. watch supply stores don't seem to sell the bushing and 2. I don't have a lathe. I'm basically at the point that I can try this because the next option is replacing the main plate and barrel bridge. So if I mess up the jewel replacement, I'm where I would be anyways. 

I measured the arbor: 

Top Pinion is 0.70mm

Bottom Pinion is 0.80mm

The bushings are still installed but measuring them on the main plate and barrel bridge comes up with: 

Barrel Bridge Bushing: ID: 0.80mm OD: 1.20mm

Main Plate Bushing: ID 0.90mm OD 1.80mm

It looks like I can get Seitz Center Jewels 30714 in sizes that will fit these measurements. Question is, how much space should I have for the arbor? For example, if the measurement is 0.70mm, do I get 76, 78, 80? 

Please let me know if you have any recommendations on this. TIA! 

[nickelsilver]

0.01mm is a usual oversize for pivot clearance, on pivots that size 0.02mm is fine. So you want 0.72mm and 0.92mm. Which works out great as Seitz jewels move in 0.02mm increments at that size as I recall.

[mzinski]

7 hours ago, nickelsilver said:

0.01mm is a usual oversize for pivot clearance, on pivots that size 0.02mm is fine. So you want 0.72mm and 0.92mm. Which works out great as Seitz jewels move in 0.02mm increments at that size as I recall.

Thank you! That's what I'll order and give a try.