TH, i usually put up a shed trap every year... I use 3 steel fenceposts like you do, but i use wire they use to reinforce concrete i believe. heavy steel wire with big openings. The wire does not bend and the deer can not get their horns tangled in it like they can flimsy chicken wire. I'll also use bungee cords on the back corners stretched across the back of the trap. Just a thought for your next design...