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screen printing => Waterbase and Discharge => Topic started by: Prosperi-Tees on May 04, 2012, 10:07:54 PM
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Are you pretty much screwed? I thought about dabbing the shirt with black discharge and sending them back thru the dryer but never tried it.
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we have successfully shot them out BEFORE they go into the dryer, On a related note, we have washed out entire plastisol prints by cleaning it with ink degradent, came right out. . damdest thing.
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black discharge and black plastisol will NOT work.
Sharpie works for tiny holes. Sometimes using a spray gun will work as well.
If the pinhole is big enough and you catach it, you can spray it with water and use a white sponge to wipe it out.
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we have successfully shot them out BEFORE they go into the dryer, On a related note, we have washed out entire plastisol prints by cleaning it with ink degradent, came right out. . damdest thing.
Are you saying that you put in degradent in your washing machine in place of detergent?
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no, we actually took the shirt off the press, straight to the washout booth and lathered it up with our ink cleaner, washed it out with the hose. . .came right out. . .that was a shot in the dark to see if it would work, it was a hoodie now that I think about it.
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Make sure you inspect the screen very well before going to press. Then make sure to inspect a test print very well before doing the run.
We use blockout pens if we have pinholes but typically we won't with our underbase screens anyway.
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I usually tape the edges where the squeegee runs when running discharge. I ran a job by myself last week with plastisol and I did not catch the hole until 40 shirts have been affected. I just thought wow I'm glad this wasn't discharge!
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I usually tape the edges where the squeegee runs when running discharge. I ran a job by myself last week with plastisol and I did not catch the hole until 40 shirts have been affected. I just thought wow I'm glad this wasn't discharge!
Just be glad that the shirts weren't garment dyed like neons.
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When we doing discharge we tape up our newmans so crazy, just to ensure we don't have any issues. Some shops might see it as a pain, but for us it's a precaution that i gladly take. Especially in really big runs.
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When we doing discharge we tape up our newmans so crazy, just to ensure we don't have any issues. Some shops might see it as a pain, but for us it's a precaution that i gladly take. Especially in really big runs.
Same here. I would rather waste a roll of tape than replace a dozen or more shirts.
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When we doing discharge we tape up our newmans so crazy, just to ensure we don't have any issues. Some shops might see it as a pain, but for us it's a precaution that i gladly take. Especially in really big runs.
Same here. I would rather waste a roll of tape than replace a dozen or more shirts.
Now I heard someone mention that taping the back side of the screen accelerates the break down of the emulsion. Any truth to that?
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Now I heard someone mention that taping the back side of the screen accelerates the break down of the emulsion. Any truth to that?
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I think that could be true. Where I tape over my marks, if the job is more than a few hundred, the tape starts to fall off. I retape with a larger piece because you can feel the moisture under where the tape was. I've had to retape two times on a 500 piece run, each time expanding the area I'm taping to make sure I hit a moisture free area all around where the last piece of tape was. I'll try blockout next time to see how that compares, and add a random piece of tape off to the side and keep an eye on it to verify.
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We try and omit reg marks from discharge jobs whenever possible.
When not possible, we place them above and below the image far
enough that we can move the print limits to avoid them after registering.
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Make sure you inspect the screen very well before going to press. Then make sure to inspect a test print very well before doing the run.
We use blockout pens if we have pinholes but typically we won't with our underbase screens anyway.
your using blockout pens for pinholes running waterbased inks?
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We try and omit reg marks from discharge jobs whenever possible.
When not possible, we place them above and below the image far
enough that we can move the print limits to avoid them after registering.
Absolutely! Works for us as well. One or two colors why bother. And you can block them out with emulsion before reg and line up to film before you put ink in. Goal is to use as less / be as efficeint as you can in regards to our tape. Well, everything really. But man, tape is pricey!
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Now I heard someone mention that taping the back side of the screen accelerates the break down of the emulsion. Any truth to that?
I think that could be true. Where I tape over my marks, if the job is more than a few hundred, the tape starts to fall off. I retape with a larger piece because you can feel the moisture under where the tape was. I've had to retape two times on a 500 piece run, each time Oi the area I'm taping to make sure I hit a moisture free area all around where the last piece of tape was. I'll try blockout next time to see how that compares, and add a random piece of tape off to the side and keep an eye on it to verify.
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that might have been me. based on observation it seems to be true. I do tape the underside minimally along the edges of the emulsion.
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My first thought is that it is not the tape that is causing the break down, but rather the collection of ink that now sits sandwiched between the tape and the emulsion.
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As alluded to above it is not the collection of ink but moisture. A hardened stencil should actually need to bleed moisture [/i]gently throughout the print process. The tape causes it to collect and attack the emulsion. That moisture contains trace amounts of discharge, resulting in the dreaded "tape lines".
One of the most common misconceptions is that you need to overtape. Discharge screens. While the opposite is true there are a few techniques i prefer I'll try to get to that later.
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We avoid tape on print side at all costs. Short run, pinhole, maybe. We use emulsion
for any touchups, exposed in the sun and hit with hardener afterwards.
Tape on ink side works well in many cases as long as you "step" it right.
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As alluded to above it is not the collection of ink but moisture. A hardened stencil should actually need to bleed moisture [/i]gently throughout the print process. The tape causes it to collect and attack the emulsion. That moisture contains trace amounts of discharge, resulting in the dreaded "tape lines".
One of the most common misconceptions is that you need to overtape. Discharge screens. While the opposite is true there are a few techniques i prefer I'll try to get to that later.
This was my gut feeling, that the screen needed to 'breathe' to hold up. I'm still not sure what to do about it regarding flatstock though. My screens don't breakdown but they get moist on the print side and then stick to the paper a little, sort of like when you print on a hot flashed shirt and it 'snaps' back off. Still prints fine just not optimal. I would imagine this is a non-issue on textiles more or less although it could explain why some can successfully print wb and disc wow and some cannot.
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we have successfully shot them out BEFORE they go into the dryer, On a related note, we have washed out entire plastisol prints by cleaning it with ink degradent, came right out. . damdest thing.
I have done the same thing and it worked for me.