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Screen Printing Author:
Kam S. Leang
Date: June 30, 2005
Summary: The following article describes a simple method for
screen printing ski graphics.
Description: Graphics of a ski are just as important in
construction as the wood, composites, and base material. They make
the ski come alive and allow the builder to personalize his/her ride.
Screen printing allows the transfer of images of almost any size and type onto
any surface without the need for expensive equipment. By using simple
off-the-shelf items along with a lot of patience you can produce high quality
graphics for relatively little cost.
Screen Printing The following description outlines one method
for screen printing. Please be aware that I am not a screen printing
expert and the following is simply a low budget way of printing.
Step 1: Gather the Following Materials
Step 2: Set Up the Screen The screen is very
easy to make and only requires the embroidery hoop and screen material.
Insert a piece of the screen material into the hoop and pull the screen near the
perimeter of the hoop until it's nice and tight. Try to get the
screen as taught as possible with no wrinkles.
You can see that the screen is made from some pretty fine
material. You can also use real screen material which is most easily found
online and available in different meshes. However, I've found that using
prom dress material works fine and is readily available.
Step 2: Clean Screen Before you proceed the screen needs
to be cleaned of particles, oils, etc. Mix up a solution of bleach (1
part) and water (3 parts). Use a sponge or cloth to apply the cleaning
solution to both sides of the screen and let dry.
You can simply let the screen air dry or you can speed up the
process using a fan. A box fan works well. Use some small sticks,
pencils, or anything else to elevate the screen from the fan as shown.
This prevents the screen from picking up any of the dirt or dust that may be on
the fan's surface and also helps insure that the screen does not get caught in
the blades.
Step 3: Cover Screen With Emulsion The key to
making a screen is the photo emulsion. Emulsion is a liquid substance that
cures or hardens when exposed to UV light. Kits containing emulsion along
with emulsion remover (for cleaning screens) can be found at Michael's craft
stores and usually costs about $25. It may be a little expensive but the
kit can make about 20-30 of the above sized screens depending on how much you
apply at a time.
For this process try to work in a dimly lit area. Remember
that emulsion cures when exposed to light so try to avoid as much premature
exposure as possible.
Apply a bead of the emulsion liquid onto one side of the screen.
With the plastic scraper spread the emulsion around the screen. I usually
only spread enough just so that it covers the size of the stencil. There's
really no need to cover the entire screen unless you're stencil is that size.
Now, flip the screen over and pour some more emulsion and spread as before.
This is all the emulsion you will need. Flip the screen over again
to the original side you started with and even out the coat again with the
plastic scraper while returning any excess liquid back to the bottle.
Keep trying to even out the emulsion on both sides until you have removed as
much excess as possible while still providing a smooth coat. They
key is to have as little emulsion on the screen as possible. On your final
spreads there should be little to no excess emulsion liquid coming off of the
screen.
Step 4: Dry Screen Using the same box fan setup, dry the
emulsion covered screen. Make sure to dry the screen in the darkest place
available. A bathroom or closet with no windows and the door completely
shut will work fine.
When drying I like to have the screen resting with the well facing towards the
fan. Most people say to do the opposite but I find that a screen that
dries this way produces cleaner prints.
Step 5: Prepare Stencils While the screen is drying, prepare
the stencil. If you have a laser printer you can simply draw up your
stencil on the computer and print the stencil directly onto a transparency (or
acetate) sheet. However, if your printer uses regular inks then you'll
need an extra step. First print out the stencil onto regular white paper.
Then use a copy machine to transfer the image onto a transparency sheet.
This can all be understood by realizing that toner from laser printers or copy
machines produces prints that are very opaque which means that it blocks light
well. However, ink from a regular printer is not opaque enough and
light can pass through.
Step 6: Expose Screen After the emulsion has fully dried,
fix the transparency onto the screen using clear tape. Make sure that the
transparency is flush with the screen and that there are no raised spots.
Lay your screen on top of something black with the well facing upwards.
Center your light source about 12 inches directly above the screen and expose
for the indicated time according to your emulsion brand.
Step 7: Rinse Screen Once the screen
has been exposed for the appropriate time rinse the screen using a garden hose
or something similar. Use warm water and begin rinsing very gently.
Once you start seeing parts of the screen disappearing then you can increase the
water pressure until all of the stencil is gone as shown below.
Step 8: Making Prints Printing with the screen is very
easy. Simply place the screen onto your material. Using the
appropriate type of ink for the job (fabric paint, epoxy-based ink, etc.) pour a
small bead above the stencil. Use a smooth plastic spreader to squeegee
the ink across the stencil. It's best to use the fewest passes possible
for a print to prevent blurring.
Note that this article only described how to make a small print
of one color. It is possible to make full-sized prints by simply making a
larger screen. You'll have to make your own custom frame and expose
the screen using several light bulbs instead of just one. To make
multi-color prints you'll have to make a screen for each separate color you
intend to use.
Some examples of screen printed graphics can be seen on
the Bird and also on the
Tao. In the Tao a total of three
screens were made. One screen had the Chinese characters on it and
multiple prints were made throughout the ski. The two other screens were
used to create the Bruce Lee image. The Bird's graphic only required
one screen that contained "the Bird" stencil shown above.
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