crazing?

Hi all, I painted a build with Alclad high shine aluminum. Most of it turn out really well, but some areas turned out crazed? motteled. I sanded them out, cleaned them real well and re-shot, same result. Any ideas why. Any thoughts would be appericated. Thanks Aardvark

It sounds like the Alclad is too “hot” for your undercoat. What did you use? If it was acrylic based (the water clean up kind), that might be the problem. Solution? Maybe reprime the affected area with a lacquer primer, then reapply the Alclad.

I have also used enamels successfully as undercoat, but have been afraid to try it over acrylics. Also, you want a very gloss finish on the undercoat, and I have problems getting a really glossy (wet look) with acrylics. So I stick with lacquers or enamels for undercoating alclad. I have varied colors, however, from a dark blue to a dark yellow/orange.

I use Alclad a lot and have never had that issue happen to me. For high shine primer I use Testors (small bottle) or MM gloss black enamels. For regular Alclads I use gloss gray enamels that produce a slight oxidized look and flat enamels for more oxidized effects.

I let the enamel cure minumum of one day before spraying the Alclad over it. As to using acrylics as a primer, Aqua Gloss is recommended by Alclad as a primer for their paints.

Are you letting the enamel cure? What psi are you shooting it at? Stay about 15-20 psi, otherwise if too low (8 to 5 psi) the Alclad will not be smooth. Each AB performs different so experiment first.

Alclad grey primer with micro filler. Thanks to everyone for your replys. Aardvark

You are welcome. Just recently used the same Alclad primer and paints on a build and had no issues. I really can’t figure out why that is happening.

How heavy are the coats of Alclad? You should be laying down light coats, not wet. Heavy application of Alclad is not necessary and will diminish the metallic effect.

Absolutely. The shinier, more polished the look you want, the thinner the coat. I know folks who complain about the cost of Alclad, but because you put it down so thin, I typically get three to four projects per bottle (except for really big airliners). You need to dial the paint flow way back. Not like putting on regular paint, more like putting on a weathering-like transparent wash.

I used Tamiya white paimer on a B-58 engine pod. I then sprayed Testors’ Metalizer Titanium. My mistake was that I did not allow the primer enough time to cure .