How much of a dial is covered by the case in a sub (vintage and modern)?

[watchguy51]

The dial sizes on subs has been 26-28mm in the various eras. I was wondering how big the dial opening is vs how much of the dial gets covered. Anyone measure?

[automatico]

This is a good question.

Back when I worked on genuine rolex watches a lot more than today, I never measured the dial and compared it with the dial opening in the case on 5513, 1680 etc. Now that I do not have acess to genuine vintage sporty watches as much (except for a 1675 that I still have) I wonder because of my 5513 and 1680 projects. My genuine common rolex watches (1601/3 etc) seem to have about .5mm or so purchase on the dial all the way around and I did not look at this detail on the 1675 when I had it apart. It's probably about the same.

 

The reason I wonder about it this is that I have read that genuine 5512/13 dials are 26.0mm plus or minus a few hundredths mm and 1680 dials are 26.5mm plus/minus. I have a genuine 1680 dial but did not write down the dial diameter when I mounted it in a DW 1680 case but iirc it was about 26.5mm. I might have posted the od on the forum but do not know where or when. I do remember that it had about .5mm of the dial under the dial seat all the way around though.

 

I have a 5513 project watch with a DW case, rolex 1520 and a 26.0mm Yuki dial and the dial is a hair smaller than the dial opening in the case...I have posted about this a number of times.

What is weird is that the dial is about .5 or .6mm lower than the bottom of the dial seat and if the movement was not mounted solid...the dial would probably come all the way through the opening in the case. The dial stays in place Ok and it is held in place only by the dial screws and this is not a whole lot of comfort as dial screws are famous for coming loose. The movement is solidly mounted in place because the shoulder on the movement (just under the dial) mounts against a ridge in the case and the two case screws hold it all in place. When you look closely at the dial in bright light you can see a space between the case and dial. 

 

I also remember a year or two back when someone posted pictures of a genuine 5512 or 5513 case with a caliper showing the dial window measurement...iirc it was 26.0mm plus or minus...now I can not find the thread.

 

Sorry for posting this a dozen times but this question still comes up now and then. If anyone has a genuine 5512/13 case and a 1680 case along with genuine dials, please post the measurements.