I'm a beginner screenprinter, and can't get my image burned into the emulsion on my screen. Please help! I think I'm doing everything right, but its not working.
Here's my situation:
I built a light box 24" x 30", and have 2 dual 24" fluorescent light ballasts mounted inside the box. The bulbs i have are F20T12BL Fluorescent Blacklight.
I have a 24" x 30" non-uv glass on top that i bought at Home Depot. The four bulbs sit about 2"below the glass. The emulsion I am using is Speedball Diazo Photo Screen Printing Emulsion. I tape my transparency to the frame(with the dried emulsion), place a piece of wood on top of the frame and two weights on top.
I've tried "burning the image" from about 4min. to 15 min. and NOTHING!
No image at all on the screen. Please Help! What am I doing wrong?
I use the photo diazo mix emulsion. I ran into the same problem. I have a Lawson exposure unit (so worth the money).
The big boys will tell you to buy a step wedge and it's about $40 and that's great if you have the $40 bucks. BUT I am a cheapskate and if I can do it for free, I'm gonna.
I have a 20 x 24 screen, if I use a 158 mesh screen or bigger I have to expose it longer than with say, a 110 screen.
We just kept trying different times over and over until we found it. We also found that after we have exposed it that it helps if we take it to the washout tub without very much bright light. Wet it, let it sit for a couple of minutes wet, then gently wash out with the pressure wash not plugged in. Strong but not too strong.
Keep in mind, we are green/newbies and it has just been learn by trial and error. A lot of ppl told us not to use the photo diazo but we love it and it seems to have a little play in it as far as times are concerned. Good luck.
Thank you! that was helpful. Do you typically use the 110 mesh or a higher one? For the mesh you use, how much time have you noticed it takes for the image to be burnt into the screen? The reason i ask, is because right now, even after 15 minutes, no image at all shows in my screen. And if i try to wash it out, the entire emulsion starts to run.
From everything i read it seems like using a light box only takes a few minutes to burn an image. Is that true?
Thanks again for your help. I'm still new to discussion boards.
Here is the deal we use. If there are words that are say sponsors on the back of the shirt or class names, small-ish, then we will use a 158. If say it were just an example, something like a nike swoosh and the word Nike, then we would use the 110 or even smaller.
We were getting the goopy gel stuff too and we found that we had a lot of humidity in the room and that the screens weren't getting "really" dry before we tried to burn them.
We didn't buy a drying unit. We have a double doored cabinet with little wedges built into the side (FO FREE) and we stagger the screens in it about chest high. We prop the doors slightly open and put a box fan slanted up toward the screens. Around the outside of the door we have a black sheet to keep any natural light from getting in.
I know, I know, at this point, you are saying what a get-up that is. HOwever, we leave the screens in there overnight. The next day they are dry. And once again, it was free and freed up money for something better (like the conveyor dryer).
Also, if you have exposed the screen long enough, it doesn't take a long time to clean out the screen with the hose/pressure washer (buy the pressure washer, $80 at Home Depot). If we use too much water for too long of a time, it seemed to get gooey.
Hope this helps. Wish I'd had someone to clue me in, even still sometimes.
Fluorescent Blacklight.............HMMMM. MAYBE ITS THE LIGHT BULBS, MINE USES 6 Aqua Coral Bulbs. NOT SURE IF THATS THE PROBLEM, WORTH A TRY TO SWITCH THEM OUT WITH A DIFFERENT TYPE
Can't get image burned into my screen. Help! 
