Description
The Stouffer 21 Step Sensitivity Guide for Screen Printing Exposing should be a print shop essential screen printing supply item. This step wedge test is a cheap, effective way to get your perfect exposure time. With a proper exposure, you will achieve durable stencils and a good washout.
Lay this strip on your screen and expose it with 3 different time increments across the screen printing frame. In this video we used 10 seconds, 30 seconds, and 50 seconds; making sure the parts of the screen that was not being tested in the time interval was blocked off. Afterwards, washout the stencil in a washout booth and examine your results.
The Stouffer strip has 21 steps with density levels ranging from light to dark to block varying amounts of light during exposure. Generally, you want the screen to be around step 7 to considered fully exposed and withstand washout. Steps over 7 are considered over exposed and you might lose fine details in the design.
If it is below the 7, that is considered to be an under exposed screen. You might see pinholes or stencil breakdown. You will need to add time to your exposing time length.
The Stouffer 21 Step Sensitivity Guide packet lists algorithm tables to help you with some simple math to figure out the perfect time for exposing. Once you have done the math for the new exposure time, be sure to run a test to make sure it is accurate.
Purchase a 21 Step Sensitivity Guide, or call 314-382-9300 or email info@golawson.com with additional questions and concerns
