Part Preparation For Powder Coating

Proper preparation is the basis of any good coating. Most powder coating failures are due to a lack of an adequate preparation so the experts at CV ALmas will take the time to prep your piece properly.

Different materials require different pretreatment methods.

First, the part to be powder coated undergoes a standard degreasing. Then, the old finish is removed using abrasive blasting like sandblasting, plastic, or glass bead blasting, depending on the type of metal, and the finish to be removed. Thin, soft, delicate metals get plastic blasted, while sandblasting or glass bead blasting are used on harder metals, rust, and tougher finishes. All rust and old finish must be removed, even the clear coat that factories often apply to polished pieces.

Next, the part is dipped in a chemical cleaner that will remove any other contaminants and residue of previous processes.

Then, the part is hung and prebaked in the oven for slightly longer, and at slightly higher temperatures than the final powdered bake. This causes 'outgassing,' or the expelling of any gases remaining in the pores of the metal. This step is necessary to avoid any bubbling, blistering, or peeling in the final powdered finish.

Finally, the part is moved to and hung in the spray booth as soon as it has cooled from the pre-bake to prevent dust from attaching. Since the booth is electrically grounded, so is the part that is now ready for powder coating.