Hi There so, following on from previous, i thought id give an update. I had an old sprue that was sprayed with Humbrol acrylic aerosol paint, left for around 2 weeks. I sprayed one section with the aerosol varnish the other was painted using liquid satin varnish. The spray reacted the same as before, but the liquid didn't. so it looks like peebeep is correct about the 'hot' stuff in the aerosol, good on ya. now I have to practice with my new airbrush. PS, the shine on the circle is from the light