I would like to perform the same feat on a watch that has a very cheap movement but a nice case and dial.
Here is my approach: (I'm still formulating)
layout:
I would search for a movement that has the same layout of sub-dials as your watch. Assuming you can find one, I would search the web for automatic movements that have the same subdial layout. You will need to search for the mechanical drawings for a given movement. Also, if the watch has a day-of-the-week or date window, this has to be at the proper radius from the dial center.
spacing:
Assuming you can find candidate movements that have the proper layout, you will need to determine if the sub-dial spacing of a given movement is identical to your watch dial.
size:
To determine if a given movement will fit in the watch case you will need to take the movement in the watch out and measure the inner diameter and depth of the case. Ofrei sells ETA movements (and many others) and lists the sizes and dimensions:
http://www.ofrei.com/page_183.html
hands:
Lastly, the hands of the watch need to have the same sizes as the new movement. The sizes for the hands are shown for the movements on Ofrei's pages. You will have to measure the sizes of the posts on the existing watch. You can buy hands that will fit - but it might be difficult to find ones that fit and are the correct length, shape and color.
For all the reasons above, I was planning to attempt this project on a watch that has no sub-dials. The multiple sub-dials really complicates things - especially with regard to the layout issue.
Issues:
If the spacing of the dial layout doesn't exactly match the new movement, how far off can it be and still have a properly operating watch?
If the new movement is smaller than the case, how should it be secured?
Are there problems mating the dial to the new movement?
I wish someone who has done this would chime in.
