Just thought that I would pass this info along, granted our structures don’t normally reside outdoors but they sometimes do get dropped/bumped/run into. [B)]
Before bonding, washing plastic pieces should be standard operating procedure. Ordinary liquid dish soap and water will get rid of any residual mold release and will not harm the plastic.
Liquid plastic cements melt the plastic surfaces together forming a solid bond. There are various brands of liquid plastic cement that work better on some plastics than others. Also make sure your glue is fresh. Old glue will not bond well.
Super glue forms an instant bond and in some cases will allow you to snap the pieces apart. While you can’t pull them apart, super glued pieces don’t have any shear strength.