So I bought another Wooden Books - this one on ‘Celtic Patterns’ (by Adam Tetlow, 1904263704) - which let me try out some spiral paterns. This one is a ‘triskelion’ pattern:
It’s just a triple spiral, really. Making it with compasses is a real pain, but doable.
Connecting the spirals up into a tiling was a little tricky, but some minor erasing got me to this:
Coloured in various greens and blues.