I have two black cages, both are black premium plastic. I notice that both of them are changing color to a more blueish hue. Has anyone seen that as well?
My black premium plastic components are taking on a slight blue tint as well. The ring is worse than the cage, but I had sanded it and figured that has something to do with it. I've also wondered if the cleaning routine could be causing it. Loss of pink or other colors on the basic processed plastic makes sense, since those colors are dyed. The premium plastic are supposedly not dyed, although there has been some recent discussion in another thread on whether the black is actually dyed onto a gray print. The shapeways info is conflicting on that.
I have had mine for well over a year now. other than just a bit of fading, its still black. I got the pa12 versions
If I understand correctly, the Premium finish does start as white and gets dyed black, so as it fades, changing to a deep blue or purple would not be surprising. PA12 starts black and is not dyed as far as I can see - I haven't cut one open to verify that, but I expect to find it black all the way through. For black, I really do recommend the MJF PA12 black, even over the premium, due to the finer layer height it prints at, and finally, now because you can get it in "smooth" finish (yay, Shapeways for making that happen!)