Problems with rattle cans is that they spew out the paint and its impossible to control the flow. Because the arc of paint is so wide its tempting to get closer to the PF in order to stop overspray.. this is when the paint becomes too thick.
its better to mask of everywhere that doesn't require the touch up and hold the can quite far back so a fine mist can be achieved.
You might be doing this already so I apologise if im teaching you to suck eggs... if not then youll get much better results this way.
if you haven't got an airbrush ( dual action) then rattle cans are your only option, but they can be quite troublesome
