HOTCAKE Wet Film Thickness Gauge (0 - 100 Mil) by Gardco

Makes measurements on slightly curved or irregular surfaces. Meets ASTM D 4414: Standard Practice for Measurement of Wet Film Thickness of Paints by Notched Gauges.


The "HOTCAKE" Wet Film Thickness Gauge (U.S. Patent 4,169,319) is so called because it is round and flat. It is an inexpensive, precision made gauge designed for on-the-job measurements of the wet film thickness of applied paints. The gauge is versatile since it can measure wet paints on objects of practically any size and shape.

Paint failures can start anywhere, but most frequently occur in corners and edges where the paint film is either too thin or too thick. When the paint film is too thin, coverage is poor, and loss of hiding and essential protective characteristics are the result. When the paint film is too thick it tends to sag and crack, defacing the film and causing premature paint failure. Overall estimates of film thicknesses are readily made, but are often inaccurate. Such errors can result in waste of time, money, and materials, as the job has to be done over. However, the wet film thickness can readily be measured with the "HOTCAKE" gauge (Fig .l). Such measurements are important to check the rate of paint application, thereby controlling the ultimate film thickness, and assuring a proper paint job. This gauge in all likelihood will pay for itself on just one job. The price of the gauge is nominal.


The "HOTCAKE" gauge can be used to measure the wet film thickness on small as well as large areas of most any size object. Examples:

  • Areas measuring only 3/ 8" x 1/8"
  • Inside and outside of pipes & ducts.
  • Thin edges & corner areas of I-beams.
  • Simple convex and concave objects.
  • On flat surfaces.

The "HOTCAKE" gauge is particularly suitable to control film thicknesses of industrial and safety coatings. There are many examples such as:

  • Aboard ships
  • Aircraft
  • Structural steel
  • Auto bodies & parts
  • Underwater surfaces
  • Above ground gas tanks
  • Railway gas tanks
  • Wood & metal furniture
  • Highway & airfield marking
  • Flammable surfaces




The "HOTCAKE" gauge consists of a circular aluminum disk with spaced, calibrated notches, and recessed flat surfaces below the rim. The hole in the center allows the thumb and index finger to hold the gauge and roll it over easily across the wet paint film to be measured. The outer rim of the disc is completely wetted, while the inner flats, at depths from 1-100 mils (.001"-.100") are only wetted according to the thickness of the wet paint film.


  • Accuracy: Stamped from fine blanking die with an accuracy of .0001"
  • Metal: Hard aluminum
  • Dimensions: 3" diameter x 1/16" thick.
  • Scale: Deep stamped with permanent numbers and letters
  • Finish: Brushed anodized aluminum.
  • Range: 0-100 mil (0-10 mil range in 1/2 mil increments)


Roll the "HOTCAKE" gauge across the surface in a perpendicular position to wet the numbered faces below the surface of the paint film. After rolling the gauge (or slightly rocking when areas are small) inspect the notched faces. The wet film thickness lies between the highest non-wetted and wetted faces.


The "HOTCAKE" gauge should be cleaned immediately after use to avoid drying of the paint. Dried paint is more difficult to remove. Brush repeatedly with a stiff brush (tooth brush) using thinner or water depending on whether paint is oil or water base.


Specify color - Gold (G) or Aluminum (A).
Corrosion Control Products Company reserve the right to substitute colors.