[fireant911]

This may be old news but I just recently came across this one night when I could not sleep and had a broken plastic cooling fan for my generator in hand. Granted, there are many materials (JBWeld Plastic Weld is one of the more popular methods) out there that bond to plastic when some sort of repair/fabrication is required but this one is quick and amazing simple: super glue and baking soda!

I have used this approach twice with great results. Simply add baking soda to the area needing material (I used duct tape to close off the bottom and sides). Next, saturate the baking soda with super glue. This almost immediately forms a hard plastic surface that can be drilled, machined, and/or sanded.

There are numerous videos on youtube demonstrating this simple, yet effective technique.