Castor bracket

thingiverse

Attach a standard office chair castor onto 1/2" (12mm) plywood for creating a portable, cat-resistant barrier. Note that the castor's shaft is angled due to it being bent by the TSA. Assemble using M4x50 bolts, nuts, and washers; insert the castor's shaft through the large hole on the blunt end. I later enhanced the design to maintain similar strength and shape while reducing plastic usage.