Well….. a quick google search and I landed on a WUS thread where someone removed the divers extension and solved their fit issue. It makes sense because we’ve long read about modern Sea-Dweller & Deepsea owners removing the divers extension and finding a better fit.
Since I’m heavy on watches for nato straps, I wanted to wear my U50P on bracelet. Removing the dive extension did the trick.
While my size spring bar is for the U50, the same concept should work on the U1 sized bracket, likely using a 20mm bar at the clasp.
Here’s what I posted in that clasp thread on WUS:
………I found myself between link-clasp fit settings: in one configuration I had the clasp adjustment as tight as possible and still it was too loose. With a link removed I was on the most loose clasp setting, but it was too tight.
Removing the divers extension, which I never use, solved the problem. Now I’m on the most loose clasp setting and the fit is ideal, no longer too tight. If my wrist shrinks in the winter, a simple pin move to the center hole will keep it just right.
While it’s true, the stock Sinn spring bar that attaches the divers extension to the clasp is too thin; there are many other types and sizes of spring bars available.
I had a bulk spring bar pack that was
originally intended for Rolex. In my case, the 17mm clasp spbar was a great fit. It appears to be 1.8 mm diameter, with a tip that is .08. I tested and found a 1.0mm tip will also fit through the hole in the clasp.
If anyone comes back to this thread, consider picking up a 17mm-18mm spring bar from Ofrei, 1.8mm diameter and with a .09 or 1.0 tip. That should be the sweet spot.
Even if you have slight play in the spring bar hole, these Sinn clasps are so heavy duty I doubt you’d ever experience a wear issue. It’s simply not the same as using a thin tipped bar in a fat hole, like Seiko or Rolex.…..
Here is the link to the thread:
https://www.watchuseek.com/threads/sinn ... s.5319540/
Edit: photos


