# Screen burning help



## farweetee (Feb 28, 2016)

Burning a screen is really burning my @%%.

I have read through some of the other posts about this, and will be as detailed as I can.

I am using 200 count, yellow mesh screens.
I de grease them, and let them dry.
I am using green galaxy cyrocoat, a thin coating, 1 on each side. 

I built an exposure unit, I use a 500 watt halogen, approx 16 inches away from the screen. 

The first time I did it, I didn't take the glass out of the light, and read that it is a uv filter. I exposed for 12 minutes. When I went to wash it out, I could see the image, but barely. I also used entirely way to much emulsion.

Talked to ryonet, and and they recommend an exposure time of 7 minutes. I did this, and the image was some what more visible, but the emulsion was not washing off the screen enough for ink to pass through it. But is was better then the first time I exposed it longer, with the uv filter in place.

The films were printed at a local printer, with a background in screen printing, so I do not think it is the film positives. 

So the questions that are running through my head are:

Is this a simple case of not letting it expose for long enough? If so,how long should I do it for? My concern is doing harm to the screen. 

Should I let the unit warm up first? If so how long

I bought a cheap halogen work light, and it came with a bulb. Do cheaper halogen builds have crumby uv light? (it is uv light that does it right?)

Any help would be vary appreciated. Thanks everybody.


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## Arcayde (Sep 9, 2015)

are you using anything to press the film against the screen? you need to have positive pressure, to 'seal' the film against the screen in order to keep light (particularly with long exposure times) from leaking in around the edges of your image.


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## farweetee (Feb 28, 2016)

Yea, sorry forgot to mention, I am placing a piece of glass over it.
It is apiece of glass I found, not sure if it filtered or not, and going to go to a place and get a nice piece, beveled, and make sure it isn't filtered.

The piece I have now is off a coffee table I think


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## Arcayde (Sep 9, 2015)

yeah, that type of glass is usually pretty heavy, you want a good 15 lbs. or so keeping it down.

My next guess would be the films just aren't opaque enough to block enough light. A good test would be to do everything you're doing now and fill it in with a Sharpie marker (if it's not too detailed) or double-up the films to make a more opaque image for exposure. Try that and see if it makes any difference. If so, you've solved it. If not, you know more about what ISN'T the issue.

Don't want to sound flip, but troubleshooting really is a bunch of trial and error. We haven't been screen printing very long, but I know that the it took me a dozen or so screens, just to figure out what it takes to dial-in the exposure for my personal combination of screen, emulsion, film, printer ink, light source, etc. All of these, in some way, affect your screen.

Let us know the results!


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## Arcayde (Sep 9, 2015)

yeah, that type of glass is usually pretty heavy, you want a good 15 lbs. or so keeping it down.

My next guess would be the films just aren't opaque enough to block enough light. A good test would be to do everything you're doing now and fill it in with a Sharpie marker (if it's not too detailed) or double-up the films to make a more opaque image for exposure. Try that and see if it makes any difference. If so, you've solved it. If not, you know more about what ISN'T the issue.

Don't want to sound flip, but troubleshooting really is a bunch of trial and error. We haven't been screen printing very long, but I know that the it took me a dozen or so screens, just to figure out what it takes to dial-in the exposure for my personal combination of screen, emulsion, film, printer ink, light source, etc. All of these, in some way, affect your screen.

Let us know the results!


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## KSP (May 30, 2016)

Next time you expose a screen, put a 1 inch square of aluminum foil between the glass and your screen near your artwork but not over it. That square should wash out in under a minute with a 200 mesh screen. If it does, and your design still won't wash out well, your positive is probably not opaque enough. Or you are explosion way too long. 

If the square doesn't wash out well either, you probably have a pre-exposure problem. ie. Too much emulsion or coated screens getting exposed to light while drying or in storage.


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## KSP (May 30, 2016)

*exposing. Thanks autocorrect.


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## NoXid (Apr 4, 2011)

You are shooting in the dark (no pun).

Do a step test rather than guess at the exposure.

Here is a link to an example I found real quick. It will at least give you an idea of what a step test is.
How to Determine correct screen exposure times using Vellum

Search that term on here and you will find lots more info (and opinions). End your frustration, test!


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