For the past few weeks our Makerettes have been experimenting with screen printing with vinyl. We had a lot of fun creating images, seeing them cut on the vinyl cutters, and, ultimately, transferring our designs to t-shirts.
There are several ways to design an image so that it will cut on a vinyl cutter. In essence, you want to create a file that the machine can understand as paths for it to trace with a blade. You can these paths (vectors) directly by using programs like Inkscape (free) or Illustrator (subscription-based). There are also ways to take regular (bitmap) images and convert them into this vector format. For instance, we used an Autodesk app called Vectorize It to convert photos we took of hand-drawn designs. We then converted our vector files to AutoCAD Interchange Format (.DXF) so that Silhouette Studio (free software that controls our vinyl cutter) could translate our paths and turn it into motion.
[box] Note: Autodesk Vectorize It is no longer available. This product, Vector Magic, will do the same thing. [/box]
Once we finished designing and generating our cut files, we turned to our vinyl cutter (a Silhouette Cameo). This cutter is essentially a machine with a blade that moves back and forth along an x-axis and rollers that feed material forward and backwards along the y-axis. This range of motion allows us to cut (or plot) anywhere within the range of the material we feed into it. In general, we cut our vinyl in to 12×12 inch squares or smaller because they fit on our cutting mat that way. Once our designs were cut into the vinyl, we removed the pieces that corresponded to areas where we wanted ink to show up.
Once our vinyl was prepped (weeded) properly, we applied it to our screens (on the side not in contact with our fabric). Initially when we first started this process, we used embroidery hoops to hold the silkscreen in place. Our friends over in the NanoLab used this method and it worked great for screen printing at a smaller scale. The smallest hoops (5-6 inches) held the fabric in place really well, but the larger ones (10-12 inches) were too loose. When the silk is too loose, it’s harder to keep it in contact with the surface you’re printing on and the the edges of your design tend to bleed. At first we ended up applying the vinyl directly to our t-shirts and using it as a stencil to paint in our designs by hand. It wasn’t what we set out to do, and we couldn’t reuse the vinyl, but we still got some cool looking results.
At our next meeting, we used store-bought silkscreens ($15-20), but one could easily stretch the silk over picture frames or canvas stretchers for much cheaper. Having the fabric taught made a huge difference and we were able to get really great results from pulling the ink (Speedball acrylic silkscreen ink) across the screen surface. This also allowed us to get multiple shirts from one piece of cut vinyl. Generally, I’ve found that the vinyl stays stuck on the surface of the screen for somewhere between ten and twenty prints. After that, the vinyl’s adhesive will wear out from the moisture in the ink and you have to reapply it.
Even though we drastically improved our methods for silkscreening, we still had fun using the vinyl as a stencil directly on the fabric. Some of our youth got really great looking effects from using multiple colors of fabric paint inside the boundaries of this stencil.
I was so excited to experiment with this process and even more thrilled by the enthusiasm our youth showed for it. I can’t wait to see what they keep making with these tools in the future!