Things You'll Need
Reusable spray can
A spray paint can, also called an aerosol can, cannot be reused. They are made to be used until the paint inside is gone, at which time they are thrown away or recycled. However that does not mean paint cannot be put into some spray cans. The secret is to find a reusable one. These cans work the same way that one-use spray cans do, yet they can be refilled with paint once they are empty.
Get a reusable spray can. They can be found at automotive stores, hobby shops or online.
Unscrew the top of the spray can. Some types have a hand screw, while others will have a bolt head that unscrews with a correctly sized wrench.
Pour in the paint. How much you add will depend on the type of spray can. For first-time use, fill the can halfway to judge how long the paint lasts.
Replace the screw-on cover.
Attach an air compressor to the air compressor nozzle on the spray can. Most cans are pressurized to about 100 pounds per square inch, but this varies depending upon the make and manufacturer.
Spray the paint from the can just like you would any spray can. Many reusable spray cans come with different nozzle heads to give different spray patterns. Choose the one that is right for your application. When adding paint, first release the inner pressure with a bleed valve on the top of the spray can. Then unscrew the top and add more paint.
Virtually all spray cans are rated at 200 pounds per square inch of pressure maximum, but to be on the safe side, never add more than 150 pounds per square inch into any reusable spray can. Each spray can will have a maximum pressure rating per manufacturers recommendations. Never exceed that rating under any circumstance.