Exposing
a Screen
Photopol Emulsion
Premium non-toxic water
and solvent resistant direct emulsion. No sensitizer required!
Exposes with a regular light bulb. Three years shelf life. Only
requires you to coat two layer (vs. four for most others).
Using a direct emulsion increases the image possibilities compared
to hand cut stencils. With the proper film, you will be able to
reproduce any illustration, computer image, text and photograph.
Materials for Screen
Preparation
- Photopol Emulsion
- screen coater
- prestretched screen
- dish detergent
Applying Emulsion
(see diagram below)
1) Clean screens with
liquid detergent to remove all sizing and/or oils
2) Work in safe-light or yellow light conditions and fill coater
with emulsion so that the it is easily distributed across the
width of the coater.
4) Stand the screen on edge and make contact on the screen side
(outside).
5) Pull upward in one even motion, while maintaining contact,
angle and even pressure.
5) "go back to point 4" and apply a second coat.
6) Dry screen horizontally in a safe-light and cool enviroment.
You may use a fan to speed up the drying prodcess but do not use
a blow dryer or other heat source.
7) Pour excess emulsion back into container and wash the coater
immediately to avoid emulsion harding on coater.
"The Plant Light"
Method
A very effective and
economical way to expose a screen using a regular plant bulb.
This avoids the costly investment of a vaccum exposing unit or
building a complex light table. This method is ideal for screens
that are less than 20"x24" OD.
Materials For Exposing
Unit
- 2" foam board
or styrofoam cut to 1" less than the inside dimension of
the screen
- 3mm thick clear glass
cut to 1" less than the inside dimension of the screen
- 150 watt plant bulb
- clamp light socket
that handles 150 watt bulb
- your film positive
- clear tape
To Expose (see top and below diagrams)
1) Tape the fim positive to the screen side (outside).
2) Place the styrofoam block on squeegee side (inside).
3) Position the screen with the foam on a table, positive side up
and place the sheet of glass on top of the screen. This secures
the film and ensures proper contact with the screen.
 
4) Expose for 25 minutes at 12-15" distance from the screen.
5) Immediately after the screen is exposed, remove the positive
and rinse the print side of the emulsion until the unexposed areas
are completely clear.
7) Blot dry with unprinted newsprint and dry horizontally.
8) Once fully dry, place screen against a window or infront of a
light source and check stencil for pinhole. Using a smal brush,
patch up with unused emulsion.
9) Once dry, the screen is ready to use.
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