Powder Coating Specification for Textured vs Gloss

If your talking surface finish of the paint, I suggest you talk to the manufacture ofeither the paint supplier or the powder coat equipment supplier.

And specify it that way.

... and if the spec cannot be proprietary? In other words, what if several coating manufacturers might be submitting proposals?

You need to request sample swatches from the suppliers, texture can vary significantly between different sub-contractors.

The texture is more in the powder paint product than in the application. I have specified powder coat both ways on the drawing, by color and by paint supplier number. I have had more success specifying a finish by using the paint supplier number.

In matching a powder finish there are three main parameters: color, gloss, and texture. The RAL system is good for the color. For gloss, % works sometimes, but is a little subjective. And then there is texture which is difficult to quantify as there does not appear to be an industry standard definition.

I have found that if a coating supplier and product number are not specified, the only way to get a good match on color, gloss and texture is to work with samples as recommended above.

I have also found that specifying a specific coating supplier and product number has not been too restrictive. If a coating company prefers to work with a certain coating supplier, they will research the equivalent and will ask for permission.

Here is a link to the Dupont Powder Coat website that has a list of publications and color cards. All the info you are looking for will be in the links on this page: http://www2.dupont.com/Powder/en_US/product_information/literature.html

Other companies will have similar publications.

Consider what environmental conditions the end product will be exposed to as that will determine the chemistry of the final coating. For example, epoxies have poor resistance to UV therefore, you wouldn't want to coat a patio table with an epoxy. Good Luck.