silk-screening: how to

A great tutorial on how to silk-screen from the craftzine.com blog
Print your designs on anything you can hang, wear, or tote. A special 101 from CRAFT vol 1: CRAFT 01 (subscription information).

Silk-screening is a great way to personalize 
your gear. It's a very basic process that has unlimited outcomes. One of the easiest ways to get a design on almost any surface is to use the photo emulsion process. Once you've made the screen, it's ready to print time and time again. Follow along as I walk my colleague Sara Huston through the process of transferring our design to 
a screen, and printing it on a laptop bag.

Work up an idea for your design. On your first attempt, try a one-color design, keep it simple, and have some fun with it. Once you get it figured out, make your design digital. Sara and I created ours in Illustrator, but you can also scan a drawing. If you are really hands-on, you can draw straight onto transparency paper using India ink. You need a solid black positive to burn into the screen. I print on transparencies, using a black and white laser printer. This gives me an easy way to accurately, cheaply, and quickly create a positive.

Gather

» diazo photo emulsion made by
» 8"x10" silk screen

» 8"x10" piece of glass
» squeegee
» task lights (2)
» 150-watt bulbs (2)
» transparency paper for black and white copier/laser printer
» silk-screen inks (createx and speedball have worked well for me)
» lid to ikea bin for stretching shirt over, or other hard flat surface you can slip into a shirt

Optional

» fan (i use a small vornado)
» diazo photo emulsion remover (if you want to clean your screen and start over)

Design

More: Go to craftzine.com/01/101 for more designs to print.

Start

Step 1: Prep the Screen
Mix the photo emulsion as per the directions.

Coat the screen with photo emulsion, working fairly quickly over a sink or surface you can get messy. 
It's OK to have indoor lights on during this process, but keep out of direct sunlight. The emulsion needs to be applied evenly, so keep flipping the screen over and squeegeeing until the emulsion is even on both sides. Any globs will cause uneven exposing and will mess up your end result. The thicker the emulsion is applied, the longer the screen will have 
to be exposed.

The screen needs to be completely dry in order to expose it, and should be dried in a pitch-black room. I dry my screen by resting the wood frame on a couple of shoe boxes in the closet, so that the screen is parallel to and above the floor. This allows the air to flow above and below the screen to help it dry faster. Make sure that only the frame touches the boxes, so as not to mess up the nicely applied emulsion. You can place a fan (I use Vornado because they are compact) next to the screen. Drying it this way takes 30 minutes to an hour, depending on humidity.

Step 2: Expose the Screen

Now that it is dry, place the screen on your workspace with the bottom facing down. Put your transparency on the screen in the center and as squarely as you can, then place a piece of glass on top. This holds your transparency down so that it makes direct and even contact with the screen. If it doesn't make direct contact, then your design will appear fuzzy around the edges.

The light source needs to be placed about 12 inches from the screen to get good results, and it needs to shine evenly across your design. I use two $10 task lights. These are great because they allow me to easily adjust my light source, and by having two, one on either side of the screen, we can make sure the entire design gets an even, direct supply of light. Follow the directions that came with the emulsion for exposing your screen. It varies with the bulb and screen size. I'll burn our screen for about 30 minutes. You can tell when the screen is done by looking: the exposed areas turn dark green when they are baked solid by the light.

Tip: For a super-dense positive, make two transparencies with your design on them. Line them up and attach them together with double-sided tape.

Step 3: Wash and Dry Screen

Now that the screen is exposed, wash it off in the sink with hot water. It takes some force to wash the screen effectively. I've attached a special nozzle to my faucet that creates higher pressure. (I got a nozzle at Bed Bath & Beyond for $5. Just screw it on and it'll toggle between high and low. Works great for dishes too; I leave it on all the time.)

Along with spraying, you can gently rub the screen with your fingers. Don't use your fingernails. If you force the emulsion off, you run the risk of tearing 
off the hardened emulsion, putting you back to 
step 1. You want only the unexposed area to wash off. Under hot water, the emulsion will become slightly gummy. Drying the screen isn't such a big deal this time around, now that it isn't sensitive to light. Prop it up against the fan, or place it where it can get some air. Silk dries quickly.

Step 4: Print It

Now that the screen is exposed, washed, and dried, print it and see how it works. Try it out on paper first.

Lay the screen down flat, making sure that your surface is even and flat.

With a spoon, put a glob of paint on the screen and spread it the width of your design. Don't get any on the design itself, just the area above it.

Now the fun part. Hold the screen down firmly 
with one hand (or have a buddy help hold it). Use a squeegee to pull the ink down to the bottom of the screen. Apply a small amount of pressure to the squeegee as you pull the ink. You will be able to see 
the paint evenly distributed across the screen.

Lift the screen and look at your beautiful print! Be very careful when you lift off the screen. Try to peel it slowly and directly up, so you don't smudge the fresh ink. It may want to stick to the paper.

It's as easy as that! Lay the screen down on another piece of paper and do a few more prints for fun.