If anyone's curious, I wanted to see how EkoPrime would stand up to abuse on an acid etch only surface vs an acid etch plus Scotch Brite scuffed surface. I primed parts a week ago and primed a scrap piece with half prepped each way. 24 hours after the primer was put on (cool weather, so I'm positive the primer still had a ways to go to truly cure), I hit it with a sharp awl. The awl cut through the acid etch only side with minimal effort. While it cut through the scuffed surface to an extent, it was not nearly as noticeable. In the picture, the acid etch only portion is the top half (right under the word "awl") and the scuffed portion is the lower half of the metal.
I tested again at 6 days, figuring that the primer should have largely cured to it's long term hardness. The primer stood up much better to the awl on the acid etch surface. On the scuffed surface, the awl really just burnished the surface. It took a fair amount of aggressive scratching to get through to aluminum at all.
So all in all, given the ease of spraying the EkoPrime (water borne - no 2 parts to mix or wait for), I'm very pleased with it. Yes, I've beat up a few areas on the parts that are having to deal with my riveting education, but for the most part all primed surfaces have held of wonderfully to the abuse of a newbie builder. For all of the empennage I scuffed every single part while using the EkoEtch. I'll likely continue to do that just because I like the added toughness, but I'd have a hard time arguing with someone who just decided to clean parts and spray with an acid etch and not scuff at all. The primer seems to stick pretty well regardless. Obviously that's only for internal surfaces that won't see long-term abuse.
I tested again at 6 days, figuring that the primer should have largely cured to it's long term hardness. The primer stood up much better to the awl on the acid etch surface. On the scuffed surface, the awl really just burnished the surface. It took a fair amount of aggressive scratching to get through to aluminum at all.
So all in all, given the ease of spraying the EkoPrime (water borne - no 2 parts to mix or wait for), I'm very pleased with it. Yes, I've beat up a few areas on the parts that are having to deal with my riveting education, but for the most part all primed surfaces have held of wonderfully to the abuse of a newbie builder. For all of the empennage I scuffed every single part while using the EkoEtch. I'll likely continue to do that just because I like the added toughness, but I'd have a hard time arguing with someone who just decided to clean parts and spray with an acid etch and not scuff at all. The primer seems to stick pretty well regardless. Obviously that's only for internal surfaces that won't see long-term abuse.