Long-time lurker, first post, be gentle. Andymac sent me. Apologies in advance for the lengthy post:
I'm having problems with peeling emulsion during washout. I'm using QTX and I'm sure it's still good. I degrease and abrade properly so I'm sure the problem is in exposure and/or washout:
My burn rig: 500 watt halogen (new fixture with no glass) 24 inches above screen. Laser vellum positives sandwiched between tempered glass and 1/2-inch black gator foamboard inside and elevating the screen off the table.
Screens: 155 white mesh, coated 1/1 and dried overnight, stencil-down in complete darkness.
I just burned 3 screens: 10, 12 and 14 minutes. All of them unacceptable. All were an easy washout, but they all started peeling during washout to some degree. The 10 minute screen peeled like a bitch, mainly around the outer edges of the positive. The 12 minute screen similar, but not so much and mainly around the edges, and the 14 minute peeled the less of them all.
I was under the assumption that peeling was due to overexposure. Is there any other factors that could cause this? Should I expose longer?
Also, I've read that halogen doesn't put off proper amounts of UV. Should I switch to another light source and if-so, what would you all recommend?
Vellums are easiest for me to use since most of my work is large format, fine art (think huge, Warholesque sort of stuff on handmade paper). Should I switch to transparencies, and if so, can anyone recommend an economical solution for transparency seps like up to 3x5 feet?
I want to get this process tweaked so I can start slinging ink again.
Much appreciation in advance, and Andy, I still owe you that beer.