A bit of a story here…
This Citizen Promaster is an aviator watch, it came to me with the 2 bezel slide rule chapter rings missing, looked like crap without them.
I looked high and low for replacements……none to be found.
But I measured it up and found that the inside diameter required was the same as the divers ring on some Rolex and the outside diameter required was slightly larger than the Rolex ring.
So I got one of those aftermarket ceramic rings for a Rolex from eBay.
I was lucky enough to find a blue that is very close to that of the dial.
Now I had to figure out how to decrease the outer diameter…..being ceramic it would need to be carefully ground or it would shatter.
This ring isn’t flat it’s has a conical cross section, this was a mixed blessing in that the conical taper allowed the outer edge of the ring to be attached to the rotating bezel while the inside had the required clearance to not interfere with the static inner ring of the slide rule bezel.
On the downside was the fact that the conical shape was going to be a bastard to hold in the lathe inorder to grind it properly round. Both of my lathes are too big to hold something as delicate as this.
As luck would have it, to see which would be best to use, I was trying out different grinding stones in the Dremel whilst holding the ceramic ring with two fingers in the middle, I found that it turned quite well on my fingers, powered by the Dremel.
I could control the speed by spreading my fingers to act as a brake. In no time at all I had it ground down to snap fit the rotating bezel perfectly with touch of adhesive to retain it there.
So now l guess I’ve converted an aviator’s watch into a mariners watch!