Misconception: Thicker Is Better
While it’s true that you need a certain mil(s) (one thousandth of an inch) thickness of material for a functional coating, it’s not true that when you’ve achieved the film thickness specified for job success that you need to apply more material.
It’s impossible to compare the thickness of one formula with the thickness of a competitor’s formula. For example, Company A may claim that its 1/4” thick coating is automatically better than Company B’s 1/8” thick coating. There’s no enforcement regarding actual thickness of a coating when it’s tested for physical properties.
However, a company with an underperforming formulation, or perhaps more focused on its profits, may encourage customers to use as much material as possible in an application. It’s possible that they may promote the falsehood that thicker is better to get customers to use more material and bolster performance through sheer quantity.
A formulation using higher quality and higher cost raw materials will perform better and cost more on a per mil basis, but it won’t need as much material to perform as good, or better, than a lower quality, less expensive material.
Companies promoting the misconception that “thicker is better” are likely offering poor quality products that are inexpensive. Avoid the false claim that you need 250 mils to get a good coating strength–possibly a result of the high filler content in their costing systems. A high performance coating using quality raw materials won’t need the same thickness to match, or exceed, the performance of a cheap, filler-laden coating. Thicker is not necessarily better.