Powdercoating

Try PCI, Powder Coating Institute. Also, you could try the manufacturer of the powder you are using. I worked for a powder manufacturer, and they will go out of their way to satisfy a customer. Try TCI Powder Coatings, 229-937-5411, in SW Georgia.

Hi, I'd be very interested in how you get on. Here in the UK we have quite strict health and safety regulations about powder coating operations. I am currently working on bringing our plant up to the Dangerous Substance and Explosive Atmosphere Regulations (DSEAR) specifications.

We currently produce a high end domestic product that is expected to have a near wet paint finish, something that has caused a lot of quality issues as you can imagine. As a result, we often have to spray over powder. In fact, we use one colour, a royal blue that is so translucent we have to spray twice to achieve an adequate coverage. We find the best result is achieved by preheating the coated component in the cure oven and spraying when hot. We have achieved good results like this, even changing colour. (As long as it's a darker colour!) Cleanliness and preparation is the key, as with any spraying process.

I am involved in fine powder processing in the UK and the work to meeting DSEAR regs is not particularly onerous. The biggest problem is establishing the Kst values for your own unique formulations as well as Kst from powder suppliers. Once you've got those and calculated the dust explosion class, it becomes rather straight forward in my opinion.

For your blue product, have you tried carefully selected grades of barium sulphate as opacifiers ? The main UK supplier doesn't tackle these things very technically but a combination of 3 parts 5 micron and 1 part 25 microns gives optimum opacity without affecting gloss. Conversely, a top and bottom cut barium sulphate with d50 18 microns gives a matt finish. Strength of the blue colour shouldn't be significantly affected

powder@recovered-resources.co.uk

Unfortunately, the powder we are using is a bespoke formulation made only for the group business I work for. (Obviously I can't mention the company here, but it's a traditional household name) Our usage compared to other parts of the group is tiny, therefore we are stuck with the powder we have. As to the plant, if I said 'no spark suppression' and 'electrical components within zone 21 area's', I'm sure you'll understand!