Paint reduction?



Wasnt sure if i should post here or in paints... I'ts a noob ? so......

I am using Autoair transparent and autoborne paints.... I have been reducing black by just making it a milky thickness. Is there a point that the paint will become useless if reduced to much?

I'm also going to change to grey.. Immortal's advice for better colour control. So how dark do I mix the grey for working in greyscale?
Black and white have to be reduced more than other colors because of the pigments. I've pushed past 400% reducing with no issues but don't recommend going past that until you really understand your paint
so is there a chart of sorts that lists colours in a 'pigment value'. i know it vary's depending on the actual colour & type but just a rough guide.
If you mean how fine the pigments are ground and what colors need more reduction than others, white, black, blue and some reds are the "thickest"
But also remember if you reached the oh crap moment of over reduction you can salvage it with transparent base.
It's not just about reducing the paint of pigment breakdown, it's also about how you intend to use the paint. If you're layering gradients, you can thin out a bunch and be okay. This allows you to get great gradients at lower psi, but you have to apply multiple layers. If you need coverage in one or two passes, you can't reduce as much because you need the color applied in a couple of passes working at higher psi. Also, the substrate limits how much you can reduce before spidering becomes an issue.

I used to paint motorcycle helmets with auto air and the surface doesn't absorb the paint, so if it's too thin, the paint will spider out. You have to have a balance between psi, paint viscosity, and how fast you move your airbrush across the surface. Keeping those things in mind determines how thin your paint should be. Painting on a forgivable substrate allows you to go higher with psi. If you're just filing in color from masking, you can do whatever you want since everything is masked. If you need to freehand, then more things need to be considered. Hope that helps.