Golfnbrew

Mick Jagger has entered the chat.

I agree, although the plastic will crack /split along one of the folds eventually, rendering it unusable

Still, that style is my goto

That’s a toilet plunger. Exactly. Sink plungers have no flange. :)

Salt, as it dissolves into the glue. But I imagine a couple of sand grains would be fine, as long as you keep it away from the visual area, since sanding might bring it out and scratch the surface

Wood species and joinery would be critical. A through tenon and an oak might be enough. Middle would likely be a bit “soft” , support would be coming from the three ends.

I lean towards two finishes. Wipe-on poly, about 6 coats, then sanded back down to smooth with 320-400 after hard dry, or Briwax, for a quick wax coating.

I am that way. I use Keeper

Yeah, back in the day of dial-up connections, we used to insert two commas