Screen Printing Forum

We use Kiwocol Poly Plus S for our emulsion and we have a Solar Beam burn unit. When we go to wash our our image the emulsion starts to peal from around the image and ruins that screen. The time is set at 900, y that is im not sure but thats what everyone keeps turning it to. I need help to fix this problem so i dont keep ruining my screens. Please Help.

How old is your emulsion? Have you done a step wedge test to determine exposure time? Distance to light source? Is your exposure unit working properly?

this might sound dumb but i dont know what a wedge test is? No one here does. We have new owners and the only one that knew anything was my mom but she passed away and i really never learned much cuz she was always here to fix the problems. Can you explain what it is please?? The emulsion is very new. Also im not sure how far the light is. We had no problem untill she was gone and now a new person showed up changing everything

Sorry to hear about your Mom. A step wedge test is simply exposing the screen at different time intervals. Cover 75% (approx) of screen with cardboard to block light, expose. After a few minutes, move the cardboard to expose more screen, continue in this fashion until whole screen has been exposed. This should give you some indication at washout as to which direction your time needs to go, more or less. There shpould be a product sheet with every purchase of emulsion or online to tell you about a step wedge, light distance, etc., for your product. For instance...

http://www.ulano.com/TechData/RLX.tds.pdf

Here is the tech sheet for the rlx I use for t-s and coro as well as psa vinyl.
Don't know about the emulsion you are using but I have been using rlx for many years with constant results.

thanks the information you sent helped us alot. and i did a wedge test and we had the time way to high so now im testing all the different mesh we have. thanks alot

I am also the daughter of s screen printer. We do machine graphics, data plates, overlays we recently added digital to our capabilities, and other various things. We have over 35 years experience. I can totally understand how overwhelming all the details can be. I'm 22 years old, i started working at my mom's company when i was 18, so i still have a lot to learn as i enter this industry. I'm here as friend, and I can always help when you need it. My advice for you to be able to learn and understand all the variables quickly, as your situation demands it, is to sign up with SGIA if you aren't already, and read there magazine called Screen Printing. I have 100's of magazines and 100's of helpful articles i can send you to learn how to reduce screen casualties. And go to the SGIA convention, it's once a year, next year i believe is atlanta. Don't worry, i didn't know what a wedge test was either.
Here's my work email: jmastro@mastrographics.com

here is the sgia link.: www.sgia.org

A yes... the magic that is the step wedge.