I decided to give Stewart Systems a go and ordered small sample cans of three colors of EkoPrime: White, Charcoal Grey, and Smoke Grey. Since I needed some pieces to spray I decided to chop up my practice wing and use those as samples. And since I was chopping those up I took a little extra time to turn to pieces of the skin into a grid of dimpled rivets that I could use later to setup the squeezers and test rivets.
I purchased the 3m PPS spray gun setup and configured it to use the 1.4 nozzle. After some testing and youtubing, I increased the PSI to about 40 and was able to get a good consistent spray with little to no over spray. I practiced a bit on some old cardboard before I sprayed the sample skins.
On my sample skins I prepared them three different ways to see how the primer reacts. The first was using Stewart System’s EkoEtch and red scotch brite pad. The second was a plane old scotch brite and the third using bon ami with a scotch brite.
I made sure these sample pieces had lots of fingerprints, some boelube, and sharpies all over.
It turns out all three methods worked about the same (from a naked eye). The EkoEtch did the best job of cleaning but the Bon Ami did probably as good. Even just the scotch brite pad did well. Really the only difference is how easily the sharpie and red lettering came off. Given ease I will probably go with the Bon Ami and scotch brite for everything.
There was a little mistake in what I ordered so I ended up with just the Smoke Grey and White on day one. The following week I setup and shot the Charcoal Grey too.
Winner for me is the Charcoal Grey