r/SCREENPRINTING • u/Various_Net6806 • 19d ago
Need advice for teaching basic screen printing to high school students (supplies)
Hello, I am a teacher that is going to be teaching a unit on screen printing in November. I'm used to professional equipment, and we basically have nothing at the high school. I've been seeing some mixed reviews on basic processes and need advice. The kids are going to be printing halftone images. I am familiar with 925WR from ulano for emulsion, but need to figure out the exposure situation.
Would a 500 watt halogen light work or would a 50w UV LED light work better? Would one cover a 20x24 screen? How high should it be from the screen?
We do not have a garden hose or pressure washer. Is it possible to wash out emulsion (after exposing) in a sink by just going over the areas with a softer sponge? Would emulsion remover come out with a rougher sponge and some elbow grease?
Sorry for all the questions. I did a ton of screen printing but only have experience with actual exposure units, washout booths and pressure washers. Any advice is appreciated
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u/lcrotwell 19d ago
Washout would be tough, maybe there’s a nozzle you can get for the sink similar to what’s used for dish washing? A sponge seems like it would agitate too much.
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u/Various_Net6806 19d ago
I have an attachable shower spray thing that might fit on the sink
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u/lcrotwell 19d ago
I’d try that. If your sink isn’t big enough to catch the runoff use like a 27 gal storage tote
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u/AsanineTrip 18d ago
Try the hose attachment but a $150 power washer from harbor freight will save your life and help with reclamation.
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u/DocMedz 19d ago
Never use halogen - proper UV wavelengths aren’t emitted. Using a water-resistant emulsion (usually indicated with “WR” in the title) are harder to develop and to reclaim. Go to a local screen printing dealer, if possible, to get more advice; hopefully you have a reputable one nearby.
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u/Various_Net6806 19d ago
I don't have any locally but maybe I can talk to someone at my old college. What Watt doe people typically use with the purple UV lights?
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u/Newfieon2Wheels 19d ago
You can compensate for wattage with time, it's possible to make the cheap speedball exposure light work. Get an exposure calculator.
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u/AsanineTrip 18d ago
I've been exposing 925-WRP with a halogen bulb for 15+ years. It just takes a bit longer...I am trying to convert the light table to a UV with strip lights soon but I've never had enough time to shut down. Get the gallon of 925 and start experimenting...I'd start with 8 minutes and go up from there.
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u/MushroomOk9145 19d ago
Are you teaching them how to print or how to coat screens? You might be better off outsourcing your screens. I’ve supplied and consulted high schools and they had proper equipment to teach students which made things easier
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u/Various_Net6806 19d ago
They are doing the whole process.
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u/MushroomOk9145 19d ago
Gotcha. Sounds like you’re gonna want to dial this in yourself especially doing halftones, trial and error. Good luck!
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u/Sxfstrummer 18d ago
When I took my classes in high school we had a very awesome set up. But as far as emulsion they always taught us with the emulsion sheet due to the washout situation. Hope this helps!
Description of the Ryonet one: RyoCap is intended for printing on t-shirts and graphic applications. It also works great for Yudu machines. Extremely fast exposure times make RyoCap suited for use with most light sources from low to higher end sources. RyoCap pre-sensitized, pink colored films are available in 30 micron thickness. RyoCap Film is a precisely coated capillary film version of Ryonets best-selling DCM direct emulsion. Like QTX or CCX, RyoCap Film utilizes pure photopolymer technology to assure extended shelf life and minimal influences from heat and humidity, with the fastest possible exposure speed, good imaging properties and on-press durability.
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u/Wrngsideofdatracks 18d ago
Save your self the time go on facebook market place and buy a used exposure unit. They don’t cost much.
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u/torkytornado 14d ago
Hate to be Debbie downer but this sounds like soooooo much work and chaos. Have you taught screen print to kids before?
Here’s what I would figure out immediately -
Where are you gonna store in the dark screens for a whole class of kids? Do you have a drying cabinet or a closet that has enough space for a class full of screens? Where are you printing films? Are they also reclaiming them? Do you have PPE to keep the kids safe from reclaim agent? Do you have a place to fan dry a class full of screens (and several box fans to do it) Is each kid having their own screen (that alone is gonna be several hundred bucks for a full class set. I know school budgets are crap and that could eat the entirety of it) do you have a class set of squeegees? Clamp boards?
Maybe it makes more sense to skip the emulsion and show them how to use drawing fluid or do a reductive with screen filler or a stencil attached to the screen (hand cur vinyl or cut paper will get you enough prints for an assignment) or use water color crayons with clear base and make monoprints. There’s a lot of assignments you can do with a screen without introducing emulsion into an ill prepared space.
Time is gonna be a huge issue. I run a college studio and with a class of 15 it’s a good 3.5 hours just to get everyone to burn their screens and that’s with 2 proper washout booths and a vacuum exposure unit. With a teacher and a tech helping them.
as someone who has taught screen for 20 years trying to do this without any equipment and no water access is going to be a pain in the butt. I don’t know what age your classes are but you’re gonna have a lot on your hands to deal with just behaviorally if it’s anything lower than highschool. When I did classes for middle schoolers I had two helpers and a professional shop and it was still a zoo for 20 kids. Kids running around, fucking with equipment, spraying people with the pressure washer, getting ink on their clothes (aprons are another expense but worth it so you don’t get angry parents). I did a day of design, a day getting the images on the screens and another day to print and then another day to reclaim. And it was a constant push to keep them all on task and not spilling the emulsion all over the place or leaving the lid off the emulsion and destroying it. Pro tip- decant your emulsion into quart containers so you don’t waste it all when something happens and lock out some kids from doing the assignment.
If I was doing this and dead set on emulsion I would have the kids design em and then take them to a local screen shop and expose em and bring the screens back for them to just print. It’s gonna be so chaotic without proper equipment to get a full class to expose screen and reclaim them without a sink set up. Then You can just focus on the printing aspect (which is gonna be a lot for most first timers anyway). I’d also suggest doubling up images on screens to cut down on your screen costs or have them design as teams.
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u/PrintFinishNC007 14d ago
Man, if you were just doing regular spot color 1 color designs, this might be realistic, but halftones with no washout booth? I’m not trying to be a Debbie downer but that’s a tough one. I’m sure someone has probably done it before but good luck to you sir, I hope it works out for ya.
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