Swapping Movements

[cskent69]

Ok experts - some help please. I bought a watch with the "Asian 21J" in it. Is it generally possible to swap this with an appropriate ETA movement if one could be sourced? I guess another way of asking is - when our dealers sell us the watches with various possible movements, are the cases simply the same (perhaps with different holders on the inside?)

[Bignasty]

Ok experts - some help please. I bought a watch with the "Asian 21J" in it. Is it generally possible to swap this with an appropriate ETA movement if one could be sourced? I guess another way of asking is - when our dealers sell us the watches with various possible movements, are the cases simply the same (perhaps with different holders on the inside?)

Only issue should be whether or not the old hands will fit the new movement. As far as actually holding the movement in the case, it should mount the same as the Asian 21j. I also imagine the dial might need to be reworked a little, but these are all unknown until you have personally tried the swap.

I'm guessing your referring to a R0lex rep? If so you'll also need to have the date overlay removed from the asian movement and reapplied to the ETA.

Jon

[ubiquitous]

I did this swap on a watch that I gave to a friend a couple of months ago. I ordered TWG's 21j Asian Auto Sub, and had an ETA laying around that fit perfectly. The only items I changed on the watch were the movement, the movement ring (got rid of the plastic one and used a metal one I had with the screws and clamps), the hands (appropriate 90/150/25 for ETA), and I changed out the bezel insert for a genuine. As for actual modifications that need to take place in order for this swap to work-

1) The dial feet need to be cut off, and the dial needs to be fixed to the movement spacer ring as the dial feet locations are completely different between the two movements.

2) The datewheel overlay from the 21j has to be swapped to the ETA (unless your ETA already has the appropriate overlay on it; in my case, I had to do the swap, as the ETA was new).

Here's what I started with...

21j Asian Auto is uncased, and here I've made the datewheel overlay swap.

Dial and hands installed, ready to go back into the case.

Finished up...

Final product.

Hope this helps!

[cskent69]

Ubi,

That is crazy outstanding. Important lesson - though - if I attempt the same thing - I have to make sure to get appropriate hands for the movement and of course the watch. That could pose a problem. I will do more research and post some more questions.

I am very interested in getting some Asian 21J GMT and replacing it with a 2893 GMT. I think that the end product will more more to reality. Looking to do this on some Omega model......

Thanks for the great post.

[ubiquitous]

cskent- It's really not a difficult swap at all- The most challenging part in the project was lining up the new overlay to be straight and even while keeping the numbers properly aligned. Other than that, it's a pretty simple job (provided you have all the parts and tools needed to do the work). If you're going to be doing this swap in an Omega, you may not have to deal with an overlay at all.

Best of luck in your project!