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Roamer MST 478


Luci

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Hi, I am working on a Roamer Mustang Indianapolis cal. MST 478, actually I have to replace the ball-bearing wheel for the oscillating weight. I have ordered it on CousinsUK but it was unavailable at that moment so they put my order pending into "My Quotes" section. Later I have bought it, on the bag is written ETA 2620 but I know that MST 478 = ETA 2638 and if you look at the technical sheet of the MST 478 there is also written whit a blue marker ETA 2638.

Question: does anyone know if the ball-bearing wheel for the oscillating weight from an ETA 2620 matches to ETA 2638 (MST 478)? I just don't want to open the pack if it doesn't.

I have attached some pics and the Roamer MST478 technical sheet.

Thank you,

Lucian.

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2342_MST 478 Roamer.pdf

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Hi  I have attached the 2620/2638 ETA service sheet for comparison.   

the MST   parts index quotes  bearing as 1497. brearing and rotor  1143.

The ETA   parts index quotes ball bearing wheel as 1497 and  ball bearing wheel  as 1498 so ther seems to be two numbers for the ETA   and one for the MST.     Therefore one may assume that part 1497 fits both movements....     Not very conclusive

2011_eta 2620 .pdf

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9 minutes ago, AndyHull said:

I couldn't say for certain, but they are the same family and probably interchangeable.

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&ETA_2620

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&ETA_2638

I think you would be best to ask CousinsUK, but my gut feeling is that they use the same bearing.

 

7 minutes ago, watchweasol said:

Hi  I have attached the 2620/2638 ETA service sheet for comparison.   

the MST   parts index quotes  bearing as 1497. brearing and rotor  1143.

The ETA   parts index quotes ball bearing wheel as 1497 and  ball bearing wheel  as 1498 so ther seems to be two numbers for the ETA   and one for the MST.     Therefore one may assume that part 1497 fits both movements....     Not very conclusive

2011_eta 2620 .pdf 2.84 MB · 0 downloads

Thank you both, now it is pretty clear to me that it should match. The bag will be opened ...

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