Someone recently called and asked about the metal ladders on parrot cages & playstands. We feel designers make the decision to keep the ladder rungs on many models 3-1/2 inches apart for the safety of the birds (so their heads couldn't get caught).  We think the trade off here is the narrow steel rungs do not provide enough surface for the birds feet to grip comfortably. We remedy this by simply weaving cotton rope through the rungs. We used 1/2" cotton rope in the image below but you can use any size appropriate for your bird.