And just a good general run through of what we have and what we need. Thanks again!
Is this anyones screen? It showed up one day a long time ago, it is too large for both the printing table and the exposure unit, so we will be passing it along if no one claims it, thanks!
Wicked!
I’m in all day Sunday. Hoping to test drive everything! Are the screens usable? And any inks available from this century?? Also emulsion?? We will need Canaletto Bianco paper. Any chance of directors stocking all of the above? Otherwise I’ll have to bring my own as Im planning on doing screen printing demonstrations for MS festival.
We’ll find out. I can’t be here this weekend though so it’ll be up to you.
Screen printing medium is from 2016 but still looks like it might be usable, if it’s junk we’ll toss it. As for inks there’s some acrylic paint which will work fine for testing. Or in general, it’s all I ever used.
Screens look a bit dirty but that’s what today is about, we’ll try and scrub a few / decide what’s up with the sink & pressure washer. We may need someone who actually knows anything at all about plumbing for help there.
Paper looks like it’s up to us as screen printing techs, we source it and ask for budget towards it. For today we’re just seeing if anything works at all and copier paper will do fine until we get some supplies. Mostly I want to just do test strips with the exposure unit and work out burn times, assuming we even have a dry screen ready to test it in time (I doubt this). We might even need to work out a yellow safe light / gel for that room anyway. Buying expensive paper before we’ve even done basic inductions seems like cart before horse to me anyway, a pile of newsprint and sending people to John Purcell is probably more sensible no?
Never had ghosted screens do anything to prints. All they’ve done for me look weird on the screen but if they show up, sure. We probably need to buy/make a few new screens anyway, there is some mesh in one of the drawers.
Seems like you’ve done this more than me anyway though so I’m happy to be corrected if I’ve made any mistakes here. Been going back through my BA notes & books about it all the past few days.
Thanks again to @asander1 for getting the exposure unit and poking me to get this all going.
I can tell you what it looks like but probably isn’t. Looks like a chemistry tank but not sure ho it is used in terms of screen printing. Does it have a plate inside that fits sung?
Nothing to gleen off the label on the bottom left I’m guessing? Could still be chemistry tank of sorts as some chemistry has to be kept at a set temperature especially for photographic uses and it’s normally done with an immersion heater.
Had a quick look might well be a dip tank for cleaning screens. You can soak the screen this way. It might be a circulation pump or a heater for the cleaning solution.
Emulsions
There are three basic categories of emulsions available: Diazo, dual cure, and pre-sensitized photopolymers. Diazo and dual-cure types are similar in that both use a diazo sensitizer that is mixed into the emulsion. Dual-cure types have a slightly different chemistry. Unlike straight diazo emulsions, the dual-cure benefits from a post-exposure, which continues to polymerize the emulsion, increasing its durability. Both these types of emulsion have a degree of latitude in the exposure time. Their main disadvantage is their relatively short shelf life. Once the sensitizer is mixed in, they will be good for only 6-8 weeks or up to three months if kept refrigerated. Purchase in quantities that will be used within this length of time.
Photopolymer emulsions employ a salt sensitizer (SBQ, or “stilbazol quaternized”) that has a much longer shelf life.
These pre-sensitized emulsions have a shorter exposure time, which requires more precision between the quality of transparency and the length of exposure. If working with the same kind of transparency all the time this can be determined and formalized in the workflow as a real timesaver. Otherwise, the greater latitude of the dual-cure or diazo sensitizers makes these better choices for a beginner.
When purchasing any kind of emulsion, look for those that are water-resistant and have high solids, and, for coarser-mesh screens, good bridging qualities.
