84 Curtain Rod Without Center Support . These rods each come in minimum and maximum length sizes, meaning they are extensible. Creep will occur over over time, and how long depends on the material, shape and load applied. Hart & Harlow 13/16in 48in To 84in Cocoa Steel Triple Curtain Rod in from www.lowes.com Also, i used a 2 wooden cabinet knob for the finials. Creep will occur over over time, and how long depends on the material, shape and load applied. Here we will be creating a simple support with a u shaped end to hold the rod.