Reducing the link bars to 4×4 threads produced a diminutive patch:
Most of the dark smudges come from optical effects in the natural PLA filament, but the second-from-upper-left armor button contains a dollop of black PLA left in the nozzle from the end of that spool; running meters and meters of filament through the extruder isn’t enough to clean the interior. I now have some filament intended to clean the extruder, but it arrived after the black ran out.
Comparing the patch with the original buttons shows the size difference:
A trial fit suggested a 5×5 patch would fit better, so …
The whip stitching accentuates the jacket’s style. We I think a glittery piping cord square around the armor links would spiff it up enormously and hide the open links, but that’s in the nature of fine tuning.
I’ll eventually see what happens with 3×3 thread = 1.2×0.6 mm links, which may be too small for reliable bridging and too delicate for anything other the finest evening wear.