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Screen Printing Tip of the Week: Setting Optimal Off-Contact



May 14, 2014

There is some confusion among screen printers regarding the purpose of off-contact in the printing process.

Basically, off-contact involves placing the screen a little bit above the platen so that it only makes contact at the point where the squeegee passes over the shirt. When the off-contact is correct, the mesh will snap off the shirt, ensuring a clean, smooth and even print.

There are several points to consider when adjusting the screen for optimal off-contact. The necessary amount is dependent upon several factors, such as:

1.    Mesh tension. In general, the tighter the mesh, the less you need to worry about the other factors. Having a screen with high tension enables the screen to have minimum off-contact. It also maximizes the screen mesh’s open area to allow the ink to flow better.


2.    Print area size. If you are printing a large area, then the ink will have a tendency to hold onto the mesh and keep it in contact with the garment, making the required off-contact higher than what would be required for a small print.

3.    The amount of ink laid down. The more ink that is being laid down, the more off-contact there should be, as the thicker ink deposit will want to hold on to the mesh.

4.    Ink viscosity. High-viscosity ink tends to hold on to the screen and not release from the mesh. So keeping the screen tension high and the mesh opening as open as possible minimizes the required off-contact.
Make sure your pallets are level so that the effect of your off-contact is maximized. Adjusting your off-contact correctly will greatly improve the overall quality of your prints.

Kieth Stevens is the Western regional sales manager for International Coatings. He has been teaching screen printing for more than 10 years and is a regular contributor to International Coatings’ blogs. For more information, visit iccink.com and read the company’s blog at internationalcoatingsblog.com.


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