We sell solid and hollow shafts as well as couplers for torsion spring systems. The solid shaft (pictured to the right of the hollow shaft) comes in 1" and 1-1/4" diameters and is equipped with a fully keyed slot. Key stock should be used when connecting couplers and cable drums to the shaft. When joining two shafts together, you will need to use a coupler. Adjustable cast iron couplers, pictured back center, can make door repair much easier than if you use a non-adjustable coupler.
Hollow shafts are also available in 11 and 14 gauge for residential and lighter commercial applications.