help with vastex exposure unit

djmp360 · September 8th, 2011, 05:28 PM

I am new at screen printing and i am having alot of trouble exposing screens using the vastex e2331 unit with the Ulano QLT emulsion. No matter what i do it seems to be over exposed and hard to wash the stencil out. Can someone please help.

sben763 · September 8th, 2011, 06:26 PM

What mesh. 100 Should be 60-75 sec with your exposure unit. 156. 45sec. 305. 20-35

Were you exposing longer?

djmp360 · September 8th, 2011, 06:48 PM

Yes the tech support guy from vastex told me 2-6 min!!! He said he was burning a screen right this second on the same unit, that did not work for me.

sben763 · September 8th, 2011, 06:56 PM

You are way over exposing. These times are from ulano using a 40w exposure. You may have to step test to find your best result. I personally use the s.e.x emulsion from performacescreensuppies. Or hifi from silkscreen supplies and have similar exposure times on my exposure unit as the ulano

djmp360 · September 8th, 2011, 06:57 PM

OH yea you asked what mesh i used. Im using 110 mesh.

sben763 · September 8th, 2011, 06:58 PM

Try 70-80 secs if your bulbs are new

2-6 min is for dual cure like cci diazo.

djmp360 · September 8th, 2011, 06:58 PM

Thanks alot for your help, im going to burn a screen right now.

sben763 · September 8th, 2011, 07:00 PM

Report your results please

Binkspot · September 8th, 2011, 07:43 PM

Get an exposure calculator and follow the directions. It will take the guess work out of exposing your screens. Use it to check the exposure time every so often or when you notice a change in how the screens blow out. It also pays to wet the screen and let it set for a min or two then wash the image out.

djmp360 · September 8th, 2011, 08:22 PM

Thanks for the advice!!! will do.