When they're close to empty, the cans of Rustoleum enamel spray paint I typically use tends to fling large droplets of paint as Funkworks describes. Useless. But if well-shaken and sprayed into a cup, these near-empty cans provide a great source of liquid touch-up paint that can be applied by a small brush to the inevitable scrapes and chips my rockets accumulate with every launch.
When we moved a few years ago, I had about dozen half full spray cans that I no longer wanted. After my wife hauled them to the local hazardous waste disposal site and paid a large fee for this service - I learned this method of disposal - Just get an empty cardboard box, cut a 1” hole in the side, spray the contents of the can into the box. Put the empty spray can in the trash.
When the can is empty of paint but still pressurized, I flip it over, hold a nail against the bottom, then cover the nail and can with a cloth or some such before driving the nail through. The cover keeps the last little "death throws" of paint contained. Then the depressurized can goes into the trash.
I remember at summer camp, we al got a good talking to. Its seems that at one of the group / cabin's outdoor excursion, a near accident was narrowly averted. Someone had tossed an empty can of Off into the fire pit. I cant' remember if it was while teh fire was going, or before it was lit. But a spray can in a fire pit does have some 'explosive' results..
another suggestions for old paint:
(works better on FG rockets. Carboard tends to... well..)
Hydro Dip Painting: Hydro Dipping is where paint resting on the surface of water is then transferred onto an object through dipping. It produces some psychedelic effects, is incredibly simple, and no two dips will ever look alike! To hydro dip at home, all you need is …
and yes, I have a 2.6" FG V2 from WM that I've been meaning to do this to for .....
funny you guys brought this up. I went through my garage and collected all the old paint cans, spray cans, weed killer (expired) flammable fluids that have been laying around etc. I just boxed them up and put them in the back of truck and took them down to the hazardous waste facility and dropped them off. It's like a drive through where you stay in your vehicle and they will unload everything for you. Pretty simple. I feel a lot I don't have all that stuff laying around that has been in the garage for way too many years.