Thermofax Screen Printing Tips

Previously posted in July 2020, worth repeating as a reminder of best practices.

We frequently get various questions about printing from customers in our Etsy shop.  Though we have FAQs on Etsy and this blog, people don't always read them.  So we thought it might be helpful to do a post of our printing tips.  There are always variables when printing, so we recommend doing test prints before starting on your project.  That way you can work out any issues without ruining the project.

First things first:
TAPE YOUR SCREEN if you did not order a pre-taped screen. See the tutorial on our blog at http://pgfiber2art.blogspot.com/p/blog-page_10.html
Find a how to print tutorial at http://pgfiber2art.blogspot.com/2014/10/how-to-print-with-thermofax-screens.html

Printing Tips:

• Thermofax printing works best on a padded surface.  On a flat surface, we use a piece of craft felt topped with a piece of canvas fabric or muslin.  The fabric serves to absorb excess paint.  (top picture below) For t-shirts, other garments, or tote bags place a piece of cardboard covered in waste fabric inside to provide cushioning and prevent paint transfer if it bleeds through; change fabric as needed; or just use a couple of layers of craft felt.  (bottom picture below)
  
  
  
  
• If you are printing on fabrics, use paints formulated for textiles.  These paints will give your finished product a softer “hand”. Some types of paint we use include: Fluid Textile Paint (artisticartifacts.com), ProChem (prochemicalanddye.com), Speedball Fabric Printing Inks, Jacquard paints, Versatex paints (DharmaTrading.com). You can also find paint at DickBlick.com and jerrysartarama.com. 

• Different paints have different viscosity; some sink into the fabric more than others. In the photo below, the white paint was thinner and sank in more and gave a raised effect to the lettering.  The blue paint was thicker and stayed on the surface keeping it flatter.
  
   
• If printing on paper, you can use acrylic craft paints. Speedball makes both textile and non-textile inks (paints). Look for the “fabric” designation when printing textiles. 
• DO A TEST PRINT.  Before tackling your project, do a test print so you know how many passes you need, how much pressure with the squeegee, and can see any spots that may need a bit more attention or may not print clearly.  Often the screen needs to be “primed” and will print better on the 2^nd or 3^rd print.  Below, the top picture shows the print after one pass with the squeegee. The bottom shows the same print after about 4 passes.  Keep lifting edges of the screen to check the print before removing the screen.
  
• Squeegees come in all types and sizes.  While a general rule of thumb is to match the size of the squeegee to the size of the print, you may not get even pressure with a large squeegee.  Our favorite squeegees to use are old credit cards and hotel keys. There are also scrapers that come in sets of 3 sizes that you can find in auto supply stores (used for detailing) or big box home stores in the paint department. If you want something larger you can find them at the art supply websites. When printing, hold the squeegee at a 90 degree angle and pull across the screen towards yourself.
  
• We do not usually secure the screen to the surface we are printing on, but if you need to, blue painters tape works well for that.  Otherwise, hold the taped edges of the screen securely while printing.
•  IMPORTANT! Before removing the screen, pick up the edges and check the print to see if you need to go over any area again.  You can carefully move your hand holding the screen to different spots to check so that the screen does not shift.  Or use tape to hold the screen in place. As stated previously, one pass across the screen is seldom enough.
• Put a line of paint across the top of the screen and pull the paint toward you.  Moving the squeegee in different directions means you are likely to shift the screen and end up with a shadow print. It is Ok to put more paint in denser areas. You are pulling the paint all the way across the screen so it may take more than you think. Dense/solid areas will require more paint and passes of the squeegee.  A smaller squeegee means you can target specific areas more easily.
  
•  Heat set (iron) the print when dry.

Clean Up:

·        As soon as you finish with a screen, drop it into a pan of room temperature water to prevent paint from drying on the screen. Paints labeled "pearlescent" that contain mica will clog a screen more quickly than those without and will need to be cleaned sooner.

·        Use an old toothbrush or fingernail brush to gently clean the screen; some paints may leave a slight stain.

·        Pat the screen dry with an old bath towel and allow to dry completely before storing.  Screens put away damp may stick to each other and cause the plastic emulsion to peel off.

We hope these tips will lead to more successful printing!