The authoritative public forum
  for Metal Finishing since 1989
-----

Powder Coating process for milled aluminium parts that have to be re-assembled

Hi, I am looking for the correct process and type of coating to use for milled aluminium parts that have to be re- assembled. These assemblies are generally made of 5mm aluminium plate and are screwed together. After powder coating they no longer fit because the powder coating film is too thick. i.e. the 5mm plate fits into a 5,05mm slot initially but not after coating.

Please help.

Charles Nel
maintaining Rail Maintenance machines. - Johannesburg, Gauteng, South Africa
2006

---

Powder coating is great in a host of ways, but the coatings are thick relative to your needs. I think the milled plates have to be thinner or the slots have to be deeper, or you need to switch to a coating system like e-coat that generates thinner coatings.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

An alternative approach would be to make the component slightly larger in dimensions (the face that needs to match up with another item). Powder coat the item then machine the interface back to correct dimension thus removing powder from that area. This method has been used for many years in the auto mkt. It could save on the cost of a new plant.

Terry Hickling
Birmingham, United Kingdom
2006