Thanks so much – I looked for those videos but didn’t find them. But I did find a number of other example videos that were fun to watch.
I’m about half way through piercing out the settings on a first pass for a ring with 5 mm stones. I’ll post some progress in a bit here. The first setting I broke about six saw blades, but it’s getting easier.
Tim, the fabrication advice above is better than anything I could add, so here’s the stone side, which is where I spend my days.
A full eternity is the one piece where stone tolerance stops being theoretical. In a halo an oversize stone can hide at the back; in a line every stone has two neighbours and a 0.1 mm step shows. Two things that save the layout:
Count from the pitch, not the stone. Stones ≈ (finger circumference + 3 mm) ÷ (stone diameter + 0.4 mm). The +3 mm is because the stones ride on the outer face of the band; the 0.4 mm is the metal between seats (about 0.3 in tight shared-prong work, 0.5 in a heavier four-prong). A US 6 in 2 mm comes out around 22 stones, in 2.5 mm around 19. Round down — a line one stone short gets a slightly wider bridge, a line one stone over can’t be finished at all.
Buy the whole row as one parcel, plus 10–15%. Most melee, natural or lab, is pulled from mixed batches, so “2.0 mm” can run 1.9–2.1. Ask the seller for a stated tolerance (±0.1 mm is a reasonable ask) and for the parcel to be filmed before it ships. For emerald cuts add: same length-to-width ratio across the parcel, or the step lines won’t run through.
I sell moissanite melee, so discount accordingly — but the arithmetic is the same whatever the stone is.