Reddit Member DrannorR posted his custom painted Galvatronus.

Taking 4 copies of Skydive and using “Folk-Art MultiSurface Purple/Metallic from Michaels.”

He did mention that the final out come is a bit sticky and not as smooth as normal Transformers.

In these situations I do recommend starting with a nice base coat of plastic/all purpose spray paint & primer. Taping off areas that will be painted later or even re-using sections that are within the color range you want. “Grays/Blacks etc…” In some situations even starting with a base coat of spray paint will even help the other paints not be as tacky after drying.