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| runmikeyrun |
 Posted: Wed Aug 13, 2003 1:15 pm |
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Joined: 15 Jun 2003
Posts: 7
Location: Cleveland, OH
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| Okay, after printing 1000s of patches and other fabric crap on my speedball screens, i ventured out and had a 230 mesh screen made for printing decks. I coated it with the speedball photo emulsion, put it under the same light as all my other stuff and after exposing it for 13 mins (the same time as the other ones) everything just washed out. I tried it about 5 more times, each time burning the screen longer and longer (got up to 80 minutes!!) and same thing, just washes out. I've never had this problem before and it is baffling me. I have since used the same emulsion to make some more speedball screens for t-shirts and have had no problems. Any ideas on why my emulsion keeps washing out of my other screen?? |
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| olivelawn |
| Posted: Wed Aug 13, 2003 6:07 pm |
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Joined: 06 Jun 2002
Posts: 3080
Location: San Francisco
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| dunno, I wonder if speedball just can't handle the mesh count? I use ulano rlx on 137 mesh count and expose for 30 mins from 2.5 feet with a 400 watt. Works pretty well. Oh and what color is your mesh? Usually you need to increase your expose time by 50% just from switching from white to yellow mesh. |
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| Lard |
| Posted: Sat Aug 16, 2003 1:27 am |
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Joined: 06 Nov 2002
Posts: 41
Location: New Zealand
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| I also wonder does your light have enough strenth to develop a screen that big |
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| runmikeyrun |
| Posted: Mon Aug 18, 2003 11:36 pm |
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Joined: 15 Jun 2003
Posts: 7
Location: Cleveland, OH
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i dunno, i'm using an 8 foot "shop light" you know a fluorescent fixture with two 40 watt plant bulbs in it. I would think it covers the whole screen it lights up half the basement...
Yeah it's yellow mesh, i'm not sure what difference that makes and how it makes any difference really.
In the mean time i've gotten the newer speedball stuff, it comes with the sensitizer dry you have to add water etc. Looks like different chemicals maybe it will work better.
I couldn't keep screwing it up i had to print shop decks for our team so i've got someone else who works at a screen shop burning this one. Someday i'll get it right. Maybe. I'll keep trying. Thanks for the advice though.
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| olivelawn |
| Posted: Tue Aug 19, 2003 1:41 am |
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Joined: 06 Jun 2002
Posts: 3080
Location: San Francisco
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yellow vs white mesh definitely makes a difference in burning times. It has to do with the amount of light reflected and absorbed by the material. How exactly it alters it, i'm not sure, but it does. I have both colors, same emulsion, same size, same mesh count. I burn the white one for 20 mins, and the yellow 30. I clipped a paragraph from http://www.chromaline.com/artbikini.html below:
By just changing from white to yellow mesh, your ability to reproduce extremely fine details will increase greatly. Dyed mesh will require longer exposure, meaning exposures need to be from fifty to one hundred percent longer. This increased exposure is needed to thoroughly expose all of the emulsion. With white mesh, you must decrease the exposure in order to attain fine lines. But, white mesh also scatters ultra violet light making it impossible to completely harden the emulsion and still hold extremely fine line detail. White mesh just isn't a good idea.
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| Drunk Engine |
| Posted: Sun Aug 24, 2003 1:12 pm |
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Joined: 11 Jul 2002
Posts: 765
Location: New Jersey!!
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Roughen the screen for better emulsion adhesion, use some sort of grit based "Commet" bathroom cleanser and a decent scrub brush, short to medium bristels or a scrubbing pad. Wet the screen and put the cleanser on, do some nice circle paterns, some side to side, some up and down, some cross hatch and do this on both sides for a couple of minutes. Then rinse clean, the water should sheen off the screen as well it should fill in the mesh evenly, then you will know it is very clean and oil free, Do not ever touch the mesh with your hands after cleaning. The only other reason I can think that the emulsion isn't working might be because it is old and may not ever develop properly. During your rinse out of the exposed screen can tell you alot about what happened, such as: If the emulsion left behind on the screen is slimey it is under exposed, if it is very hard it may be over exposed and can cause you to use more pressure and do the old blowout.
[ This Message was edited by: Drunk Engine on 2003-08-24 14:21 ] |
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| runmikeyrun |
| Posted: Tue Aug 26, 2003 12:46 pm |
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Joined: 15 Jun 2003
Posts: 7
Location: Cleveland, OH
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Thanks so much you guys, i'll try the comet idea and i've since gotten some new emulsion that i'll try as well.
Mike |
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