Hackaday reports that a hacker has gone DIY with powder coating, avoiding the need for the usual electrostatic charge process by using a 3D-printed fluid bed chamber to successfully coat metal parts in a colourful and durable finish.
Fluidisation of the dry powder is achieved using an aquarium pump, with a coffee filter to contain the medium.
As with professional powder coating, the parts to be coated are preheated to enable the coating to adhere, and then baked a second time to cure it.
Comments on the article suggest that agitation of the powder may also be helpful, and that a filter is not always necessary.
The biggest challenge with this approach is the removal of bubbles in the coating, which can be caused by outgassing of impurities in the metal, especially in older cast aluminium.
Pros bake uncoated parts at a specific temperature to fully remove bubbles before coating.
The ability to successfully coat cast aluminium parts is a tricky problem in the industry and well-earned knowledge for the author.
