Stripping Powder

Question:

What is the best media to use if I have to strip cured powder coating using abrasive blasting? I know that stripping this way is not the best method, but it is the only method I can use at this time. In the future, I hope to install either a burn-off oven or some type of chemical stripping system. We have both suction and pressure-pot hand cabinets along with pressure pots on our walk-in blast rooms. Any help that you can provide will be greatly appreciated. B. W.

Answer:

The key questions you must ask yourself are: “What do I want the blasted product surface to look like?” and “How fast do I want to strip these products?” Depending how you answer these important questions determines the type of blast media you should use. Because not everyone answers these questions the same, there is no common answer for all powder coating stripping situations.

For instance, you can select a very aggressive media that will remove the powder coating quickly if you don’t care how the substrate looks after blasting. The blasted surface “profile” is measured in mils and described by terms like “near white metal surface.” However, if your product has a delicate surface and you don’t want it to be rough, then you should select a less aggressive blast media. Of course, this less aggressive blast media will take more time to remove the powder coating from the part.

The best way to try different blast medias is to contact a blast media supplier that has a variety of different medias to offer. Often a local distributor can represent many media types and companies. They will suggest a plastic media if you want to keep the product surface untouched. Conversely, they will recommend a more aggressive media (aluminum oxide, garnet, etc.) for faster stripping speed, leaving the product surface rough.