I have gone back to always using a light colored primer (gray or white) on brass simply because I have found -convincingly so- that the utterly flat finish offers an opportunity to see clearly, iron out, sand out, and eliminate blemishes that are so often impossible to perceive until you see them on the terminal finish coat. I do the same on resin, styrene and wood. Like others reporting this change back has been eased by Tamiya after studying the raving reports of its use coming from the military and car modelers. If it interferes with detail, it is detail that -thankfully- I do not perceive.
Scalecoat I sticks to well prepared brass like no other, and wears like iron. It is expensive to use, and its long ambient air-time dry-time may not be for those expecting to quickly handle, mask, or move on to other work on the model. i have thrown out more Scalecoat I over the years than I have used- by far, the latest just an hour ago (grainy and clumpy). Its shelf life is distinctly erratic. Ditto with Scalecoat II, but not to the same extent.
As has been amply reported here and elsewhere, TruColor has many reported and personally-experienced issues adhering directly to brass, resin, and styrene. It is a fine paint and I find that the solution is to only apply it over a primer coat. Not a big deal. Most applications of model primers have been over-thick IMHO. All one needs is a light sweep that barely covers. The cost of the Tamiya primer is such that it alone offers sufficient motivation to be careful.
Denny
Denny S. Anspach, MD
Sacramento, CA 95864
