Wiper arms get covered with rust over time, and the natural wish is to bring them back to their original look. How do you paint them properly?
First, every trace of corrosion has to be removed from the arms. Loose rust is cleaned off with a wire brush and sandpaper. At the same time the old paint finish can be scuff-sanded with fine sandpaper or an abrasive pad.
Any corrosion left after the mechanical work must be treated with a rust converter. Even if it looks like nothing is left, the traces stay in the form of very small craters, and active rusting starts from them again. The KUDO® range has two types of converters: a regular one based on phosphoric acid and a rust converting primer based on formic acid. Either of them neutralizes corrosion well, but they are used differently.
The phosphoric acid rust converter KUDO® KU‑70005 is applied to the surface, repeated after 15 minutes if needed, and left to work for 30-40 minutes. The converter is washed off with water and the surface is wiped dry immediately. In that time the rust turns into hard iron phosphate that holds firmly to the metal. The surface is degreased with Silicone remover KUDO® KU‑9100 and primed with one or two coats of 1K acrylic filler primer KUDO®. It is better to take the gray one, KU‑2201, so that the spots missed by the black paint are easier to see. The primer needs at least 30 minutes to dry, and then the paint can go on.
Before Rust converting primer KUDO® KU‑2601 is used, the surface must be degreased with Silicone remover KUDO® KU‑9100. The rust converting primer is then applied in two or three coats with no more than two minutes between them. The treated parts are left to dry for 24 hours. In that time the rust turns into iron tannate, which is easy to tell by the color change from the typical orange to black. Why wait a whole day? The excess acid has to evaporate so that it does not damage the paint finish later. In return, this rust converter does not have to be washed off, and the surface needs neither degreasing nor priming — the paint can go straight over the rust converting primer.
Once the surface is primed, the wiper arms can be painted. 1K matt automotive repair paint KUDO® KU‑5232.5 is a good choice here. Apply it in two or three coats with five to ten minutes between them and leave it for two hours to dry fully. Done: the wiper arms look as if they had just left the factory.
Materials you may need
