I posted a while ago about having a haze left in some of my screens after rinsing off the unexposed emulsion. I got some suggestions and figured i was either overexposing or there was still some emulsion running into the open areas as the screen dried.
I did a test screen to pin down my exposure time, and I'm not having any better luck. I can also see that it's not emulsion running into open areas, it's that I can't get the emulsion out of those areas to begin with. I didn't have this problem with the first print I did, and it's driving me crazy that it's getting worse and worse, as my skills should be improving.
I'm using reclaimer, power washing, and degreasing the screens, and there's definitely no haze before I recoat them. I think I'm getting better at coating, more even and thinner, one coat on each side. Could too thin of a layer of emulsion be the problem? Or maybe the emulsion wasn't completely dry when I exposed it? The films I've gotten recently have also been darker than what I started with, so that shouldn't be a problem. The only other thing that I can think of is that maybe it's too bright where I'm rinsing the emulsion out, and it's locking in before it all rinses away.
Sorry for the length of this post, but this seems like such a stupid problem to be having, and I really can't figure out what the hell is going on. Any suggestions?
After you expose your screen and washout the stencil, what do you use to clean out the stencil? Do you dab cotton towels on the screen? I use an air compressor with an attachment to blow the excess water out of the screen. That way I know nothing is lingering. Also, when I coat screen I make two passes on the outside and one pass on the inside. mmmm......
i have that problem also, im using Ulano ultra fast textile pink stuff. i usually wash it after exposing, put a fan on it wait for it to dry almost all the way wash it out again. if that doesnt work i keep a windex bottle full of water handy on the thinest setting do a few test pulls and blast the stubborn spot its a bit messy,if they are still there i hit it with the power washer as a last resort and hope i dont blow out the stencil.
Your emulsion could be old. If so it will take a blast with the widest SPRAY of the power washer.
Your film might not be dark enough. What are you using for film?
You could still be overexposing your screens.
What light source are you using?
It most likely is not the light that is in the room during washout.
Thanks for the help. I'm thinking that my problems today are different than I had before, and you guys are nailing all of it. The first time I had a problem with the haze my emulsion (image mate/franklin diazo stuff) was less than a month old and and I had a film positive made at a printshop. So that time I bet I didn't get the stencil clean enough after I washed it out.
By now my emulsion is pretty old, and today I used inkjet transparencies for film. The first screens I burned today for 90 seconds in the sun. I also tried my tiny flourescent setup on another screen for about 45 minutes, which is probably too long now that my stencils are thinner. That screen wouldn't wash out at all. The inkjet transparencies look darker than xerox ones i've used before without problems (aside from registration issues), but maybe light doesn't think so... the black definitely has the other ink colors in it as well.
So I guess I'll try to find some new emulsion tomorrow (anyone know any good stores in the hudson valley/westchester/northern nj area?), coat my screens a little thicker, get different films, make sure the screen is clean after washout, and this damn thing better work.
thanks again, guys.
Your emulsion should still work ok but you are going to have to use your pressure washer on it carefully to get it to wash out.
Try getting some Krylon Crystal Clear and spraying it on the dull side of your inkjet film. That should do the trick. It makes the ink on the film much more opaque.