How To Do Silk Screen Printing

For people who have asked how to put their art or logo on placemats,
umbrella hats, etc.
This is a quick, easy process once you are actually making
one print after another from your screen.

It takes an hour or so to make a silk screen.
Then you can re-use it for a long time.

Check the search engines or your local city for silk-screen supplies.

BACKGROUND: Silk screens are a type of stencil made using fabric stretched
over a frame and treated with special chemicals. They are used
to do many things including: make tshirts, make concert posters, and make just about
anything else you need multiple copies of. It was a favorite format of Andy Warhol and
you can do it in your own home!

MATERIALS:
1 Screen (see note)
1 Kit containing photo emulsion and activator
1 Squeegee
1 Printing inks (see note)
1 Duct tape (a.k.a. "Duck" tape) or Masking Tape
1 Whatever you want to screen on to

Note: Your friendly local well-stocked art supply store should sell pre-made
screens as well as all the other supplies. Otherwise, check out art supplies
distributors on the 'net. For inks, use textile ink for shirts (it's thicker and flows
on to fabric better); use standard printing ink for posters or whatever.

You can make your own screen frames out of wood, polyester fabric (as the "silk"),
and some thick string, but that's for the more advanced screener.

Also, don't be afraid to ask the store people for help, they usually
have some good tips and can clarify any questions you have.

1: PREPARING THE SCREEN
Mix up the photo emulsion according to directions on the box. Keep in a cold, dark place (i.e. the fridge).
Usually, the emulsion stays good for about a month or two depending on brand, but in my experience,
it has a quality curve. During about the first week or two, it's too goopy on the screen and washes out
easily. Also, within the final weeks of its life, it gets harder and is more and more difficult to wash out.
Try it out and find your best experience.
Wash the screen in water with a little mild soap. This washes out any manufacturing residues and helps
with emulsion adhesion. Set in a breezy spot to dry.

Select the design you want to screen and photocopy it onto a transparency.
This can be done at your local Kinko's, etc. Make sure the design looks okay and keep in mind that although
silk screening is a fairly precise art, it is impossible to achieve perfect resolution in your own home.
Again, play around with it.

When the screen is dry, apply the emulsion to it using the squeegee.

START WITH A SMALL AMOUNT! As with anything, a little goes a long way.

Make sure to spread it on both sides of the screen and get it into every corner.
Watch out about using too much, if you use too much it will drip all over the place and get very nasty.
Once you get a nice coating, set it in a cool,
DARK place to dry (i.e. the cupboard). Make sure it stays out of the light as the emulsion is light-sensitive.

Get yourself a large piece of black paper and set up several bright lights
above it.

When the screen is dry, place it on the black paper (the paper should be
big enough so it covers the surface underneath the screen and absorbs
any stray light) with the "bottom" side up.

Use tape to secure the transparency (making sure it is backward) to the
screen in the area you want to use.  Try to keep the tape to the borders.
Tip: Instead of tape, use a large piece of glass
or Plexiglas to press the transparency to the screen.

Any part of the screen that is not exposed to light (areas covered by the black
on the transparency, taped areas) will wash out.



MAKE SURE THE GLASS IS CLEAN!
Expose the screen under the bright lights for approx. 30 min. Follow the
instructions on the emulsion.
When the time is up, wash the screen under a steady stream of lukewarm water.
The stream will wash out where the transparency blocked out the light.
It does take a little time for it to wash out, so be patient when washing.
Lightly rubbing the areas you want to wash out will speed up the process, but be careful
as you may rub out an area that you want to keep.

When the screen is washed out, set it aside to dry. The emulsion should've formed a
plasticy coating on the fabric.

When the screen is dry, take the duct tape and tape all around the outside edge where
the screen meets the wood. This will prevent any ink from seeping under and coming out
when you don't want it to. Also, tape anywhere else where there isn't a design as this will
strengthen the screen and make it last longer. When this is done, you are ready to print!

2: PRINTING
Before producing a final product, the screen must go through several test
prints to check for leaks, etc. This is done on paper. Try to use a heavier
paper as it absorbs the ink better.
Place the screen on the test paper, making sure to protect the surface
you are doing this on.
Take a spoon or similar utensil and place a fair amount of ink across the
top edge of the screen. The ink should be anywhere from thick but flowing to peanut butter consistency

Take the squeegee and use it to drag the ink across the screen. You should do this once the first time and then, depending on the thickness of the ink application, you can repeat back and forth as many times as you need.

Check the printed product: Is there ink where you don't want it? Tape those areas (after washing the screen). Is there too little ink on the paper?

Do more passes with the squeegee. Once you are satisfied with the product, get ready to test it on the final items you want to screen.

FOR A POSTER: Simply repeat the test procedure on the poster paper.

FOR A TEE SHIRT, ETC: Wash the shirt first. Place a thick piece of
cardboard inside the shirt under where you want to screen so the ink
does not seep through. Make sure the shirt is flat and perform the
procedure used to make the test print.
Silk Screen Printing: Addendum

Two major things wrong here: First, you don't want to coat the entire screen
in emulsion, leave some open screen around the edges of the frame.
This uses less emulsion and makes washing the stencil out of the screen easier.
Now, use 2" masking tape, buy it at the dollar store, they always have it and it
is 200-300% more expensive anywhere else. Use the masking tape to tape
the edges of the screen and frame.

Do the top and bottom of the frame plus the inside of the frame so you can
lay your squeegee against it. This makes clean up a breeze since most of the
screen is covered in cheap disposable tape.

Second, you want to coat the image (to be printed) with ink while the screen is not touching the printing media.

Depending on the inks and the size screen you use, under certain situations
the ink can run right through the screen.

I prefer to coat the image on the return stroke,
lay the squeegee up against the frame,
then remove printed media (T-shirt,etc)for drying,
Replace with new (blank) media. Lower the frame, and repeat.