The thumbnail version:
- A decent exposure unit is an essential item of equipment
- You have research to do
The full version:
I once heard a screen printer explain how he exposed screens when he started out in a small shop in Hawaii. He said that his dark room was a grass hut and his exposure mechanism was a grass curtain in the ceiling that he drew back with with a cord and pulley mechanism. The sun was his light source. This was how he burnt images into his coated screens.
He had figured out the length of time he had to draw back the curtain and “expose” the screen. Obviously unconventional, and definitely not recommended. First of all, Canada is not Hawaii, but secondly, we want to start you off using the right equipment because you can be sure that your competitors are not drawing back a reed curtain to expose their screens!
An exposure unit built by a reputable manufacturer is an essential piece of equipment. Quality matters. Precision matters. You also have to decide between a bulb unit, a UV unit, and an LED unit. LED units are a little more expensive but worth the investment because they last longer than UV bulbs, they use much less power, and the stencils are sharper.
Do your research. Ask the folk at Stanley’s; they can help and advise.
Finally, if the investment is a bit steep when you’re starting out, use a screen-burning service until you’re ready to make the investment in a good exposure unit.