In this free tutorial video is for the professional screen printer training on this screen printing learning website. Tee shirt printing only is a complete screen printing industry and other branches of screen printing are each separate industry.
If you are moving towards the professional screen printing at high level preparation and device usage then first of all you should be well aware with proper use of devices and statistics of time and quantity which are very basic rules for each industry.
Here you will learn about how to use Exposing Unit (professional exposing machine used in screen printing industry) and how much time it takes for complete exposure. Although there are flow charts for this purpose available on inter net but the type emulsion, power of the exposing machine can vary. So the time may be different.
The proper exposure time is very important because under exposure can result a very dull stencil on the screen and over exposure may cause damage to the screen mesh, under design cover opaque area or it will take a lot of time for washing away the stencil area paint. Therefore, before you use the exposing unit you make a flow chart for exposure time and light intensity to be provided in that time by the exposing unit.
Requirements:
Unexposed, dry and photo emulsion coated screen.
A dark opaque design pattern on a transparent sheet, having small repeated design shapes on it.
UV (ultra violet) opaque mask or anything which opaque to UV radiation
And of course Exposing Unit
Procedure:
- Place the screen on the exposing unit for exposure.
- Place the resolution step art tool (transparent paper film with small repeating designs pattern) on the screen where you want to create stencil.
- Then place UV opaque mask over the film any allow only one small design of the pattern to be exposed to light. The rest of the paper film should be covered with the UV opaque mask.
- Then turn on the exposing unit and for different time period and intensity note then time.
- After every exposure is complete remove the UV opaque mask from one design further. And apply same intensity for different time period.
- Once the process is done for every design part of the pattern, wash the screen with water pressure, the best stencil created on the screen show the perfect time period for exposure to that Exposing Unit and Photo emulsion.