April 16th, 2009 by Chris Tomkins-Tinch | Posted in Uncategorized | 2 Comments »
Using a design created by maker Jason Sauers, Make Club printed T-shirts on April 10, 2009. We created our own screen using a painter’s canvas frame and polyester sheer curtain from the home decorating section of our local fabric. While the DPI of our homebrew screen was not as great as the commercial alternative, it worked just fine. We created the screens using the standard photo-reactive screen printing process, and used commercial screen printing ink. Here are a few photos of the endeavor:
Stapling the sheer curtain to the canvas frame from the side centers toward the corners:
We folded masking tape into the sheer curtain to keep it from fraying as we put tension on it:
The end result looked just like a commercial screen:
There was still a gap near the bottom of the mesh that we needed to seal with masking tape to prevent runaway ink:
Since the photoemulsion applied to the screen becomes impermeable after exposure to UV, we used a cheap halogen worklight as our UV source since the quartz lamp envelope is transmissive to UV. (The front glass pane and protective grill were removed.)
After the photemulsion is applied, it needs to rest in a dark place to dry.
A stack of laser-printed transparencies mask off the areas we don’t want exposed to UV.
The exposed areas become impermeable to ink and water, while the unexposed areas (under the black of the transparency) wash right out and allow ink through.
We exposed the screen using the “500W” setting for 13 minutes at 0.3 meter.
After exposure and washing out the covered areas we can see right through the screen. These ares are where it will print our design.
We repeated the process for the DIY screen:
Which one is which? (Hint, the commercial one is on the right.) The DIY screen is six times cheaper than the commercial alternative and still looks pretty professional.
At our regular Friday meeting we put the screens to use printing shirts:
At first we did this outside, but this caused the ink on the screens to dry too quickly and clogged the screens. We later moved inside.
We experimented a few different colors. The ink is water-soluable, so the screens can be cleaned easily. This makes switching to a different color a snap.
Multi-color designs were a popular choice:
Toward the end we got creative with color gradients.
We printed everything in sight to use up our excess ink.
