I plan to build a playgym for my birds. I have a basic idea that would result in something a bit like a rope ladder: stacked sticks joined and held in place by two parallel ropes. The sticks/perches need to be easily removable and replaceable for cleaning, so my thought was to tie semipermanent loops into the ropes and then pull the section of rope immediately above the loop through the loop to make a slipknot, then put the end of the stick through that. The slipknot would be held tight by gravity as long as the stick is there to keep it from pulling free entirely. It would be also be easy to loosen, which is important, because the sticks are natural manzanita branches, so the loop needs to be able to expand to allow irregular twiggy bits through and then tighten to hold securely.
The rope will most likely be polypropylene cord because it's durable and doesn't fray easily, which makes it safe for birds as long as they don't eat it.
I don't know anything about ropes or knots except what I can read in books or on the internet. Is there any reason an alpine butterfly loop wouldn't work for this? Would pulling the adjacent bit of rope through to make another loop mess with the tension or something?
(My birds are budgies, so their weight is negligible and they're not very destructive.)
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