thanks for the replies! I'll at least try it for situations where I'm not going to blend with ppg base coat.
I know that many times when you dissolve two polymers (plastics, high molecular component of resins, etc...) together in a solvent and then let the solvent evaporate, the majority of combinations will not be completely misciible once the solvent evaporates -this would be especially true in non catalyzed systrems where you don't have chemical crosslinks to keep the different components from phase separating.
Note that some degree of phase separation is normal and even desirable - it is one of the factors behind the incredible performance of todays clear coats - but if the size of the different regions gets near the wavelength of visible light, thenj it gets cloudy... Many resins would phase separate on a much larger scale than that.
from what I read above, spi's interecoat and dbc500 miust be close enough in composition to be miscilbe / compatible even when mixed together. I'll probably give it a try and report back down the road.
the specific applications I'm thinking of are mixing bdc 9700 (black) 1:4 with bdc 500 or spi intercoat and including some large grain silver pearl and shooting a few coats of that over black. It works great with dbc5oo and gives a deep, deep looking black with some subtle sparkle in it. The other would be to add a little dbc9700 1:10 or so with intercoat and use it to tint tail light and marker light lenses... that also works great with dbc500.
If I wanted to give the intercoat a little more strength and adhesion, would I add a small amount of activator to it? if so, which one, how much, etc... Thanks!