Primer base coats are not always necessary, there are times when they are a good idea and would be recommended but there are also times when they may not be recommended. There are certain powder types that would yield undesirable results when used with a primer base coat. Wrinkle finishes should be applied directly to the substrate with no primer or other base coat. A primer coat or other base coat can hinder the powder from wrinkling, thus causing an inconsistent finish (see Figure 1).
Always be sure to ask if you are uncertain whether or not a primer should be used.
Conditions where a primer coat (epoxy or zinc/epoxy) would be recommended are conditions where corrosion is more of a concern, such as harsh weather, coastal environments or other conditions of high humidity. Prismatic Powders may be applied over bare metal substrates and yield good results, but a primer will add further protection to the metal substrate.
Figure 1: the image portrays the result of a wrinkle top coat that was applied over a primer base coat. Notice the inconsistent texture towards the the left corner.
