Now the ring is made it needs to be made perfectly round with flat front and back. So it gets put into the lathe.
In this case I'm cutting the inside of the ring first, to get this fully concentric, and clamping the outside. There is no particular preference or benefit of doing the inside or outside first since both should be near circular from the hammering.
Then I cut the front face,
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and, I can't remember but, I'm assuming I raised the piece off the back clamps a little bit otherwise the cutting graver may crash into the hardened steel clamps.
I then re-position the piece with the clamping on the inside, then cut the outside and other face giving this:
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The ring has been cut to the correct diameter and is now ready to fit into the recess of the middle watch section,
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