You can also take the Aztec tips apart to clean them. I do it often, and have had no problems in doing so. With Future, I would use alcohol to clean the tips, as ammonia might attack the plastic that the tips are made of. Just be very careful with the metal needle that is in the tip: it's EXTREMELY sharp, very small, and easily lost. You can also buy new tips at any store that sells Testors airbrushes. They cost, on average, about $10 US. Hope this helps you out.