My instinct would be a constrictor or double constrictor (for extra security). ...
If you try the constrictor knot, bear in mind that it is difficult to untie (by design!) but if you tie it near the end of the boards you could slip it off and then the knot will fall apart.
1) Knots such as the
constrictor that require pressure
against the bound object for security are NOT what should
be used here --the flat boards won't give much of that (to
a likely not-so-large-diameter binding rope).
2) And the difficulty of untying the
c. is overstated,
too much parroting of Ashley's "... have to cut it off"
nonsense (esp. for some users who might be in other
instances employing a marlinespike!).
3) Now, one can form a sort of
Gleipnir'd constrictor/
by making a
clove hitch in hand such that one casts
each *half* past the other (i.e., oriented so that one is
looking at the cross section of a cylinder onto which the
formed knot is to be placed, with ends coming from left
& right, the loop formed from left would be thrust
rightwards past the opposite (left end's loop) loop/half,
AND THEN
rotate one or other (or both halfway) around the central
crossing "bar" of the hitch and bring loops back into
ready-to-place-over-object position.
.:. The above turn puts a "
turNip/nipping turn" into
the crossing part, and thereby gives nipping independent
of the object.
(And the crossing of ends that makes this a version of
constrictor is IMO gratuitous --one would prefer the
basic
Gleipnir, but that knot isn't tiable in the bight.)
--dl*
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