Wolfgang recommends:
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If it moves.....AT ALL.... cinch it down a bit
tighter.....and repeat.
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Hmmm.... do you all concur?

(1) At NO movement, would I not risk twisting my plastic boat (almost
18') out of shape?

(2) If I use a foundation of foam, should I not expect to get movement?
(In my case I've got a Queen size mattress worth of fairly high density
foam -- for a mattress that is -- to play around with and cut into
whatever shapes I need). How do I not get movement if I'm using foam?

Cheers,
Wilf
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