How to clean anodized aluminum

[Walter R.]

When our house was built, the stucco person did a poor job of applying the stucco around the patio doors and windows. He splashed stucco on many areas of the black anodized aluminum frame.

It's only cosmetic but it looks sloppy. I have chiseled off any actual stucco from the frame but cannot remove the remaining blemishes on the black frame.

To make things worse, when the house was repainted about 10 years ago, the painter, too, did a sloppy job and smeared white paint on many areas of the black frame and thresholds.

How can I clean up the stucco blemishes and the paint? I have tried alcohol, and goof off, and paint remover, without success.

Thanks

[Richard J Kinch]

Methylene chloride paint remover for the paint. Nasty stuff but supremely effective. Not a lye based remover as this will eat aluminum.

Stucco is easy to remove with acid, but that eats aluminum. I would get off what you can mechanically, then spray on CLR (or Zep clone) acid cleaner (milder than muriatic acid usually used for cement cleanup), scrub, and rinse quickly as soon as the residue is loosened. Polymer-modified stucco is tougher because the admix makes it resistant to acids. Experiment on an inconspicuous area first.