It shouldn't hurt them laying on their side as long they are properly shaken before use.



on the side or upside down,i have like 2000 cans strored on the side,make sure that you shake each can after every 6 months.
So you keep track of which of the 2000 cans you have were used in the last six months and shake those not used?

Probably the best way to store spray cans is upside down. The feed hose goes to the bottom of the can and if the can is upside down and the paint thickens it will not foul the hose.
Twarren..........
Toss 'em when their used. Buy them fresh when you need them.
It's one of those things where you'll save a bunch of partial cans and ten years later when you need them they'll be dried out or a crappy spray pattern that'll screw up your project.

This thing is kind of cool for shaking the cans. I have never used it though.
http://mixkwik.com/
BTW, I see no problem storing them on their side.
