I've never had this problem before and i'm wondering what it could be. I just bought some new 110 screens and coated them last night. At least a good 20 hours later I burnt an image onto one. I have really fast exposing emulsion (the pink stuff) and it usually burns under a min and a half. I set it to 1:10 and it completely washed out. I tried it at 2:30 and it washed out again. Should I have washed the new screens first? Is my basement too cold and the emulsion just didn't cure properly? And if it is too cold is there a way I can keep them warm down there like maybe a little heater? Thanks for any and all reply's
110 mesh screen holds like 3 times the emulsion of a 230. Coat them once on each side (if you're a good coater) or skim off the excess emulsion with your scoop. They will take a long time to dry. Cold may be a factor in them not drying right for you, but 20 hours sounds long enough. What's important is the the inside of the coated emulsion is dry as that's what's sticking to the mesh. Sometimes screens feel dry but aren't. Try getting a dehumidifier for your basement and keep your screen right next to it.
I've had that happen with brand new screens before, and I've remedied it by cleaning the screens first. Usually a spritz of Simple Green and a hose down are sufficient - no need to get crazy with scrubbing.
if you didn't degrease and prep the new screens, pretty good chance your emulsion will come off - there is a lot of machine oil on the new mesh. Dehaze and degrease - did your water sheet off with no spots or bubbles? that's the sign of a properly degreased screen. anything else and you risk it fukking up down the road in the process.
SQ3 is right too on the humidity thing - include with that to make sure the mesh is DRY before coating -coating a damp screen is a no no. A little humidiy reader with temp guage is $10 - for best results, you want your humididty to be less than 50% for 3 hours if you are printing long runs of waterbase ink, this gives you the strongest stencils. your screen could sit for 20 hours but if the humididty is 80-90% it won't completley dry and chemically cure.
All 3 of these problems will cause what you are experiencing....plus (don't you just love this process????)
Don't be afraid to up your exposure time - a 110 screen will require 1/2 or more time compared to a 160 mesh screen. Underexposure is one of the main reasons for stencil coming off. If you have diff meshes and diff colours, you should test and note the exposure variation for all your stuff. Start a list next to your lamp.
Yeah yeah, I know this is all TOO complicated, TOO much to do, TOO much testing, TOO much information.
then again, having to remake a screen, especially on a deadline, that's TOO much fun isn't it?