Screen Printing Forum

This is my first attempt at this so I wasn't surprised to see a complete breakdown of the screen.
I am using Ulano Proclaim (blue) (Came with a starter package I ordered) on 110 mesh. Went with 1 coat on each side.

I used a homemade exposure unit consisting of 4 24" 20w bulbs (they say GE sunshine F-20) lights are about 3 inches from the glass.
Went for 5 minutes.
Washed it out with a light spray, no more than 2 or 3 minutes, water was cold from an outdoor source and as soon as I could see my image it was a fuzzy melting mess. Even the edges of my positive started to wash out.

I am assuming I just overexposed the hell out of it, but just wanted to hear if anyone has some advice.
Thanks

If everything washed out you way
UNDER exposed it.

Try again and double the time.

Then I'm more confused than I thought.

Not EVERYTHING washed out, just any detail around the graphic and fonts.

?????????????????????

I have one drying now and am gonna give it another shot tonight.

Now ya see what happens when ya read a post ina hurry!!

Sorry.

The exposed areas stayed right?
(The areas outside the image)

The image edges were fuzzy.
The larger areas washed out OK.

Then, yes you over exposed it.

Also not knowing how dense your posi is can be a bit a of a problem.

Vellum?
Inkjet?

You also will experience undercutting with tube fluorescent lights.

We use unfiltered black lights (tubes) and burn for 90 seconds.

-Rob

90 seconds wow.
Yeah, I looked up some things and I think I am having an undercutting problem. I think the tubes are a little too close to the glass which I will adjust.

I am just using an inkjet film positive.

Yes, for the most part the exposed areas stayed correct, there was some peeling and melting kinda thing going on- not sure if this would be from over exposure or my coating or what, but most of it was just around the corners of the screen which I would've caught with some blockout tape anyway.

I'm assuming the lights I am using are "grow lights"

So I guess the question is, stick with this and mess with it till I figure it out? Or make some adjustments and just get a 1000 watt single bulb?

Wattage is useless if it's the wrong kind of light.
It also generates heat which can cause emulsion to set up as well.

You need a good amount of UV.

We use Phillips tubes # TL 40W/03RS Super Actinic.

How are you attaching the positive?

Describe your exposing procedure.

I tape my postive(ink side down) to the substrate side, lay it on the glass. I put a black cloth on top and box for some weight.
Thats about it