Tall 'Presley' perches for hawks

Some photos of the tall rotating 'Presley' type perches. The older, rust colored one is the template design for the others which are stainless. The inside of this one has a ball bearing (packed with axle grease) at the top of the post where the top of the perch meets the rod. Note the welded pipe washer that locks the separate 'ring' to the top of the post. These perches all spin. Although I told the welder to put a ball bearing at at the inside top of the stainless perches, I don't think he did. They do not spin as freely, but are sufficient. The rope length is this (a stiff rope 3/8", changed annually). I use a stiffer roper rather than the previous para-cord to keep the swivel from flipping through itself.  Bring the rope to the top and over the top of the ring, then have the knotted length touch the ground. That way if the rope gets over the top, the hawk is not dangling beside the perch. The swivel is a size 8 Coast lock Sampo. Again, changed annually. The distance of the bath pans from the perches is important. Have the well away from the perches, to keep the leashes from becoming wrapped around, yet the hawks can fly down and reach them easily. Also keeps mutes out of the bath pans as well. The plastic soda crates serve two purposes, one is to let the hawk have a safe alternative perch on the ground after a bate, also to place food upon. That way they can feed off the ground, away from insects, and when we travel, lawn chemicals in an unknown area. They are trained and encouraged to NOT feed on the ground, to prevent this. I've had birds become ill and lost a Barbary falcon due to lawn chemicals poisoning. The house where I was weathering the birds did not use lawn chemicals, but their neighbor did (using a commercial lawn care company).
So, the training to feed on a perch, or on the crate is essential.