After attempting to make do with too-big inherited thimbles, I finally have one that fits. 13 mm was harder to find than medium sizes, so I bought online. (For anyone else in need of a small tailor’s thimble, there’s also an Osborne #5 that’s 13 mm. I haven’t seen smaller.)
Lacis thimble sizes are listed by the diameter of the inside at the base. I wrapped a strip of paper around my middlefinger where the base of the thimble will sit, just above the top joint, then measured the paper and divided the 41 mm circumference by π to get the 13 mm diameter.
For something cheap, it makes a huge difference to my speed and comfort, and now that I have one that fits, it doesn’t feel clunky to use. The trick now is not to lose it.
I’m still working on men’s coat V8940. And I recently hand sewed the buttonholes on a blouse as practice for when I get to that part of the coat. I really enjoyed it.