Choosing & Using a Viscosity Cup- A Complete Guide
Why Get a Viscosity Cup
Viscosity cups like Ford and Zahn Cups are handy tools at as a painter. Whether your spraying wood finishes, industrial enamels, or anything in between a paint viscosity cup allows you to know just how thin your paint is. Additionally knowing the viscosity of your paint allows you to have a reference range so you can select equipment settings that will let you achieve a consistent result when painting. In fact if you are having a lot of inconsistencies in your paint process, especially if you’re a manufacturer a viscosity cup can help reduce the issues you are having by providing a standard process for your painting. You can learn about other helpful ideas to help reduce errors in your manufacturing paint process here.
What You Need to Know When Selecting a Coating Viscosity Cup
There are a variety of viscosity cup sizes and types which will cover different ranges of viscosity. They use the amount of time the material takes to flow through the cup to help you determine the viscosity in centipoise. For spraying paint with a spray gun paint running between 15 – 30 seconds in a Zahn 2 Cup is ideal. However a lot of times you may have a thicker coating with a higher viscosity. To select a viscosity cup that will match the needs of your painting you can check the coating data sheets for your coatings and see if a cup is referenced. You can then consider a viscosity cup conversion chart that shows the range of viscosities a particular cup can measure. From this type of chart you can see that Ford 4 Cups cover one of the greatest ranges of viscosities.
How to Use the Viscosity Cup
Once you have selected a viscosity cup the next thing is to know the desired viscosity ranges of your coatings. Once you know the desired ranges you can add thinner until the coating is within the desired viscosity range.
After confirming the coating is properly thinned you would then right down the time the material took to begin breaking the fluid stream and this would give you your viscosity. With the viscosity range written down you then begin setting your paint application equipment to achieve the proper appearing finish you want. If you are unable to achieve the desired finish, try to see if your viscosity is to high (the paint is to thick) and add thinner as indicated on the technical sheet. With the viscosity written down and the equipment settings adjusted you will have a repeatable formula to achieving a paint finish.
Using a viscosity cup for painting can drastically simplify and improve your painting but you need to know the right cup to choose for your coatings, how to use it properly, and to write down the settings on the viscosity cup and your paints. By doing this you can be better prepared to select a viscosity cup and achieve more consistent better results from your painting.