In order to create great screen prints you have to understand the concept of off contact screen printing. When you are looking for crisp, clean prints you need to use off contact screen printing. We show you everything you need to know.
What is Off Contact Screen Printing?
When you are using a screen printing machine you lower the screen down to the platen. A small gap is left between the screen and the platen. This is known as off contact. When you go to print you will take your squeegee and either push or pull it along the screen. As you are moving the squeegee along the screen it makes contact with the screen. After you remove the squeegee the screen will snap back into its off contact position.
Why do we use off contact screen printing?
As stated previously, it keeps the sharpness and the crispness on your print. If the screen is allowed to remain on the substrate then there is a chance of too much ink getting on it, or that it will start to bleed.
What should the distance be between the screen and the platen?
It all depends on what you are printing and what you are printing with. You will alter your off contact measurement based on the thickness of the garment, and the type of ink that you are using. Ultimately, it is not much. You’ll need to decide what size works best for you. It can be 1/32” up to 1/4”. If it is a thicker material then you will need more of a gap, so a taller shim. If you are using plastisol ink then you need a taller off contact. T-shirts work well at 1/16” when printing with plastisol. If it is water based ink then you need a shorter off contact. Something like 1/10” will work for that.
How do I achieve the size for off-contact printing?
You use shims. Shims are typically pieces of wood that wedge between something to fill up space. You will basically take shims and place them on the platen in each of the corners of the print. This will elevate the screen just enough so that the screen will spring back up after you have run the squeegee along it.
Like we said 1/16” works perfectly for t shirts. A quarter is about this size. So you will take four quarters and place one in each corner. (If you are using water based ink then use a dime instead. It is about 1/10”.)
Once you have you shims in place you will need to turn the off-contact knob to adjust the print head on your screen printing machine.
The Final Word on Off Contact Screen PrintingAs you become more adept at screen printing you will learn tips and tricks for making prints. Off contact screen printing is one of the tips that will take your screen printing to the next level. If you need more help with off contact screen printing we created a video tutorial for you as well.