How to Test Coating and Thickness

Dip a metal spoon into a pot of soup, stew, jelly, sauce or other food liquid to test its coating and thickness. If the liquid runs and drips down the spoon, it is thin and will not coat well. If the liquid remains spread over the spoon without dripping, it is thick with a durable coat. If loose clumps or peaks adhere to the spoon, it is very thick and will easily coat or spread.

Test the coating and thickness of paint, primer, varnish, sealant, oil or other hardware liquids and fluids by quickly dipping a wooden paint stick 2 inches into the container and then drawing it out. The thickness of the coating left on the paint stick will help you determine how many ounces or applications of the substance to use, or with what utensils.

Test the coating and thickness of fluid chemical agents and cleaning products by spraying or applying a small amount of the product onto a suitable test area, per package instructions, before use. To test the coating and thickness of foaming tile cleaner, for example, apply a small portion to a single tile before spraying an entire wall to determine how much of the product to use.

Cut a test piece of coated part, plastic, food item, wood or other small, coated object in half and measure the thickness of the film or coating with a measuring utensil or under a magnifying glass or microscope.

Use a magnetic pull-off thickness gauge to test the coating and thickness metallic, nonmagnetic coating fluids such as melted pewter and iron. Thin coatings will cause a stronger magnetic attraction than thicker coatings, which will have less magnetic attraction and be easier to pull the strip away from.