I inherited a nice little Speedball silkscreen kit from a student who left and never used them. I got some inks, some photo emulsion, some drawing fluid, and even some screen cleaner. I worked dilligently on my design in black and white as I wanted my first attempts with silk screening in 15 years to be rather simple. So i worked up from a sketch I did on the train in my sketchbook, into illustrator to vectorize and clean up the image, and then got the designs printed on transparencies. The first thing I realized was that using an ink jet printer to print on a transparency sucks. The ink never fully sets, and when I put the transparency on my silk screen the ink actually smudged. So that’s the first lesson learned, next time I need to go down to Copy General and have them use a laser printer to print off my transparencies for me. Anyway, I secured the transparency to the screen with a piece of glass I found on the street. It was perfect as it was a piece of a dresser or something from Ikea so it had a heavy wooden frame around which helped keep the transparency in place. I then took my silkscreens out from my bathroom (it’s dark in there) and laid them flat on the ground and exposed them using a 1000 watt tungsten bulb. I researched the exposure times for this type of lamp and found out that it should only take like 10 minutes! wow. that’s fast but I’ll go by my research since it’s just a test (I later learned it’s often good to just make small test strips on a screen and expose them for different amounts of time as opposed to exposing an entire screen). So I expose the screen, and I get to the bathroom to wash it out, and suddenly, my whole screen starts to wash out, the stencil wasn’t burned into the screen at all and all of my emulsion was washing out. The Silk Screens were washing out completely. I was perplexed as to why this would be, and deduced that I must have exposed the screen for too short a period of time, so I tried another screen, this time exposing it for 35 minutes. Same result again, so I hopped over to /r/screenprinting and finally asked the question. Within a few hours I got a response that these speedball kits come with a separate agent called a sensitizer, and this should change your emulsion green when it’s mixed together. I had always used this red/orange stuff in the past and never had the need for a sensitizer. There’s also the possibility that since I got the screen printing kit from someone who never used it, that the emulsion was simply expired. I found out that some emulsions have a shelf life of only a few months. Anyway, I’ll have to do another experiment, these things always take time but at least I’m happy to know what I did wrong.