RE: [textualcriticism] KANTHAROS and the Great Magical Papyrus in Paris
As "a stone" [אֶבֶן] is a component of a wall [קִּיר] or λίθος a component of τοίχου, so כָפִיס / κανθαρος must be a component of עֵץ / ξύλου. I would therefore propose a more traditional reading of "knot" for the Greek and "rafter" for the Hebrew.
Whenever I’d read the LXX to this verse, I had always imagined a beetle hiding in the wood. I found the image of the insect crying out rather humorous.