I have a JMB v2 case/bezel that fit the Clark 25-22 crystal. I'd always preferred the full dome 25-21 vs the top hat 25-22. After cracking a few 25-22's, I'm pretty sure because I rounded down the top hat to a smooth radius, I finally made the change up and went with the suggestions here and got the WSO bezel and Clark 25-21 crystal. Thank you all that answered questions so readily and those that post their progress and process.
I do prefer the overall slimness of the JMB bezel vs the WSO so I took jewelers files to it and thinned the profile, both top and bottom. Measured the newly installed 25-21 crystal at 30.52-55mm. Opening the I.D. from the delivered 30.4mm to 30.49-50mm was easier than I expected. I marked the bezel at 12,3,6,9, with a sharpie marker for visual reference and mounted a dremel sideways in a vise with a new 10mm x 16mm stone wheel, slowest rpm. Holding bezel lightly, but orientation securely, hand flexed, in one hand with 2 fingers and lower the inner surface to the wheel and rotating with the other hands 2 fingers. Check every 3-5 rotations until acceptable. Chamfered the inner 90 degree corner to ease onto crystal. Finally, rolled up tube of wet/dry 320 then 600 grit and done. It slid on with a bit more pressure than the JMB which I hope is fine.
One note about the crystal differences. The domed Clark 25-21 has an inner shoulder around the perimeter that rides slightly above the rehaut and the top hat Clark 25-22 does not. The "wall" thickness of the 25-22 crystal opening is the same whereas the 25-21 has a step around the inner perimeter that is thicker overall acrylic.
Thanks again to all here. This place is dangerous though. Now I'm trying to figure out how to make a real gilt dial with out my own printer. Decals, I can do but I can't justify buying a printer for a handful of future dials. Hmmmm.
Left- new WSO bezel Right- JMB bezel for 25-21 top hat crystal
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