I dropped out of my 5th year of college to support my habit of sleeping in till noon and playing video games. One day, after dusting off the orange cheetos powder from my fingers I decided that there was no job on planet Earth that I could hold while keeping my sanity. I decided that day to start my own business. Art, painting, drawing, designing, and creating: These were things I loved to do and needed to find a way to make money off of them.
T-shirts are a part of our culture and never go out of style. It's art anyone can own. I needed to find a way to put my Art onto T-shirts. This is where Screen Printing comes in.
Screen Printing is a simple concept but the techniques can be very difficult to master. I'm like a level 55 out of 60 in terms of screen printing mastery. There's always new stuff to learn and new evil screen printing monsters to slay.
Chapter 1: Equipment:
This is my baby:
(This is my baby. It's a Printa 770 and it's faster than a speeding bullet and can shoot lasers out of it's eyes. I love it. )
Screen printing is basically creating a chemical stencil on a mesh so you can push ink through a design and on to a T-shirt. Sound confusing? I'll teach you the three basic steps on how to Screen Print. 1) Coating a Screen - 2) Burning a Screen - 3) Printing on a Shirt
Chapter 2: Coating a Screen
There are 3 things you need to coat a screen.
1) Screen - These are tightly stretched meshes over a wood or aluminum frames. Find out the mesh count of your screen. A higher mesh count picks up more detail in an image but does not let as much ink through. A low mesh count will have bigger holes and will allow more ink to pass but won't be able to hold as much detail. (I use a 160 mesh count screen)
2) Emulsion - This is a photosensitive thick liquid used to coat a screen to create a stencil. When this liquid is dried and exposed to light for a long period of time it hardens and becomes waterproof. This will be used to create the stencil of your image on the screen. (I use Ulano QTX)
3) Scoop - This is a metal trough used to apply the emulsion on a screen evenly.
2) Fill your Scoop with Emulsion.
Use a generous amount. You can clean the scoop up later and put it back into the bucket of emulsion.
3) Tilt your Scoop so the Emulsion touches the screen.
Angle the scoop so the emulsion evenly
4) Pull the Scoop up so you coat the screen with emulsion. Scrape off excess emulsion back into the scoop
Use a fluid motion so you get no thick areas
5) Turn the screen over to the other side.
6) Coat the other side of the screen the same exact way as Steps 1-4
7) Scrape the excess emulsion in the Scoop back into the Emulsion Bucket
8) Find a dark place to dry your screen where no light can get in.
I like to dry my screens for at least an hour and a half but it will vary depending on the humidity. To be safe I would say at least two hours. The machine I use has a cabinet for screens and uses a fan to dry them so it dries quicker.
Once your screen is dried you can move on to the next step. Chapter 3: Burning the Screen.
Chapter 3: Burning the Screen
Items used: (Transparency Paper + Hose + Lights + Coated Screen)
Burning a screen can be very tricky. It takes a lot of practice and trial and error because it takes a while to get down a good system. What you're basically doing is making an impression of an image on the coated screen using light. Hopefully you'll understand once you see some pictures :)
Transparency paper is what they use for overhead projectors. The black print on the Transparency will block light from hitting the emulsion on the screen. You can also use Vellum Paper but I like to use clear ones because I'm used to them.
2) Tape your Transparency on your exposure unit or light box.
If you don't have a light box you will be taping your transparency to the dried screen you coated and then you will burn the image using a regular light bulb (Takes about 30-45 minutes)
3) Place your emulsion coated screen on top of the Transparency image then cover the screen with something so light doesn't bend around it.
Use a weight to hold it down flat.
The time you leave it on the light box varies depending on image detail and your set up. I usually leave mine for 2:00 minutes because I use UV lights. It can take up to 30-45 minutes for a regular bulb. When light hits the emulsion it creates a chemical effect and "hardens." Whatever was blocked by the Transparency paper ink stays soft.
4) Wash the screen out in a dark area with a hose and a nozzle.
The parts of the emulsion coated screen that were blocked by the ink on the Transparency Paper wash out because the light didn't harden it. If you burned the screen correctly the image should wash out in a few seconds.
(I use a 25 gallon plastic trash can so I can wash screens in my garage during the day so I don't have to do it out in the sun light. I also like to use the flat setting on the hose nozzle to wash out the screen.)
5) Tada! Now you've got a stencil on your screen that's ready to be prepped and printed on.
So you kind of understand, right? It's like developing film. You use light to burn an image on a photosensitive chemical on a screen and then wash it to create a stencil for printing!
It's time for the printing! Chapter 4: Printing the Shirt
Chapter 4: Printing the Shirt
You've done the hard part already so don't worry. Now you'll only have to do the tricky part! You will first need to prep your screen for printing and then use a squeegee to push ink through your stencil on a shirt.1) Position your screen and lock it down on your machine.
2) Use tape to mask the perimeter of your image.
Don't use cheap tape if you plan to reuse your screen. It will ruin it.
3) Put a glob of ink on your screen and place your squeegee behind it.
4) Center your shirt on your Platen (printing table).
You might want to use some sort of liquid adhesive to hold your shirts down especially for multicolored shirts.
5) Set your screen back down on top of your shirt and pull the squeegee towards you.
I like to make two passes with the squeegee. One to lay a coat of ink and another to push it through.
6) If you've done it right then your image should have a clear detailed image on your shirt!
7) "Cure" the ink on the shirt by heating it using your Curing Unit.
The time will vary depending on what you're using to dry your shirts for. I heat my shirts for 40 seconds. If you want to print a multicolored shirt you'll have to repeat all the processes of coating a screen, burning a screen, and printing an image for each additional color.
Whew. That was a ton of work. If you have any questions I'll be happy to answer them. :) Please check out my ebay store for my T-shirt designs
If you enjoyed it and found it informative please leave me good feedback :)
Thank you,
~Mark Lim
~Mark Lim
