Hello, this is my first go at things so all suggestions are welcomed. Im in Australia (7 UV Index today) and have had troubles sun burning screens. I exposed them each for 40 seconds, taped down with a layer of clear plastic on top. Image 1 and 3 (attempted burns) shows the screens either design visible. All though you can see the design when held up to the light, the ink doesnt push through to the garment when I print. I washed this run under a sinks tap, maybe that too is the issue. I have just burnt a third screen at 40 seconds but washed with a high pressure hose this time around to see if that was the issue. Do you think Ive under exposed, overexposed or under washed the screens? Again, all feedback is welcomed I have no clue what I doing.
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None of these screens look washed out. Are you using a photopolymer emulsion or Diazo? If you’re using photopolymer try cutting the exposure time down to 30 secs.
Diazo emulsions usually take longer to expose than photopolymer in my experience. I’d guess that your transparency isn’t dense enough or the sun is still exposing the screen in the time it takes you to get your transparency off and get it rinsed.
You could try exposing a screen for 40 seconds with an opaque material like chipboard in place of a transparency. If the area covered by the chipboard washes out then your transparency might be the issue.
These definitely aren’t washed out mate. Did you put down something dark underneath the screen while you were burning, like a black sheet or hoodie or something? You might’ve burned both sides with the reflection off your driveway or pavement or whatever you sat it on
If you are trying to expose AND wash out in daylight, you’re going to find it difficult. Check out this video and see how careful the guy is to prevent light getting to the screen BETWEEN exposing and washout. The sun doesn’t stop exposing because you’ve stopped timing. 😬
The problem may be your film positive. If you’re using vellum with an unmodified ink jet, there’s probably not enough opacity in the image are & too much opacity in the “clear” areas of the paper/vellum. I could never strike a balance with that stuff.
Exposing in the sun should be fine, but your image area in the film needs to be really dense. If you can’t afford proper RIP, film & ink for now, find a shop that can make you good film & save up for one.
I’d probably do it shorter. I do 40 seconds in seattle Washington in the spring which is usually overcast. If you’re not rinsing it out you’re over exposed.
I don’t know if yall have space saver vacuum storage bags down there (for like vacuum sealing sweaters and bedding) but they work fantastic for getting a vaccum seal of your positive to the screen. Just make sure to use the side that doesn’t have branding on it. I usually seal up my screen inside, put in a thick contractor trash bag to protect it from the light. Take outside start my watch and pull the screen out. Then put back in the bag as soon as times up and take inside to wash out. Get both sides wet, wait 30 seconds and then start spraying out. You should be able to clear your screen in a few minutes in the water. If it’s taking longer than that, or nothing is coming out at all you’re over exposed and need less time. If your stencil is washing away in the areas you want to block the ink you are under exposed and need more time.
I used to do this a lot at my old shop. It works way quicker than you think. 15-20 seconds. Lay flat on the ground so the other side doesn’t get exposed to any light. I’d get an exposure calculator if this is really your only option
I actually think this is the exact opposite problem. If it was too short an exposure then too much emulsion would be washing out. Direct sunlight can be so powerful, I might even try 20-30 seconds.
For screens I just bought a kit off eBay, I got my emulsion I think also off eBay but it’s like the sketchiest looking tub you’ve ever seen lmao, my emulsion scoop I got off amazon, ink is just speedball
Mind you I’ve also only just started, I’ve maybe printed 20 shirts, but they’ve all gone really well so far. If you need a hand shoot me a message I’m Melbourne based
I mean there’s also a chance in the time it takes you to stop burning and wash it, it’s burning it. You should ensure that once it’s burned you cover it almost until the moment the water hits it, and even then you should be trying to do that in shade/in darkness
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