no image appearing . . test step wedge complete flop! help!

Post your questions, suggestions, ideas and advice to issues you have run into in your screen printing shop.

Moderator: Moderator Team

Post Reply
tylah_4
Just Browsing
Just Browsing
Posts: 2
Joined: Thu Aug 07, 2008 10:21 am

no image appearing . . test step wedge complete flop! help!

Post by tylah_4 »

So I made a light box, two feet by two feet, 200w bulb in middle with tin angle down from top edges by glass. . Diazo photo emulsion. . tried recommended 17 minute exposure from box, which seemed really long cause my teacher had a similar light box with only five minute exposure time. . then guessed again at four minutes, then ran a test wedge revealing more of the screen with a manilla folder every forty five seconds, up to three minutess. . None of the time did any image wash out. . could subtelly see image on both the seventeen and four minute trial after a while, but nothing would wash out. Did not show up at all on the wedge.

I print on velium wih my epson stylus printer. . the screen gets stored in a box in my cool basement to dry for a day every time. . then after exposure i run outside to wash it out with the hose. . I don' t know if this short exposure to the sunlight is causing the problem, or the printer, or the emulsion, it was a couple months old, but I mixed up a new batch yesterday and coated a screen. . I am hoping to figure out the issue today when I get home! Don't know what else to look at! AAH
User avatar
ROADSIDE
Administrator
Administrator
Posts: 458
Joined: Fri Feb 24, 2006 4:36 pm
Location: South Jersey
Contact:

Re: no image appearing . . test step wedge complete flop! help!

Post by ROADSIDE »

ok... for starters, a few minutes to walk to the yard should not effect anything. (maybe if you live on Mercury)
Now doing an exposure test is a good idea if you do it correctly.

Can you post a picture of you exposing setup?

ALSO is you film JET BLACK?
Your screens really need some good air to cure properly. Having them in high humidity with low circulation could be a problem.

Read around on the forum..... post some pics so we can see for ourselves

GL
T
.... I can give you my opinion but I can't tell you if it's right or not.
InnoThread
Just Browsing
Just Browsing
Posts: 4
Joined: Sat Aug 09, 2008 1:47 pm
Location: Orange County, CA
Contact:

Re: no image appearing . . test step wedge complete flop! help!

Post by InnoThread »

When I first started I used to walk out back to wash out my screens as well. The sunlight was in fact overexposing the screen on the journey. Before you take the exposed screen outside wet both sides of the screen with a spray bottle.
http://www.InnoThreadGraphics.com
Custom Screen Printed T-Shirts and Graphic Design
User avatar
d fleming
Moderator
Moderator
Posts: 546
Joined: Mon Apr 03, 2006 3:33 pm

Re: no image appearing . . test step wedge complete flop! help!

Post by d fleming »

What type of bulb are you using?
zynthesis
Just Browsing
Just Browsing
Posts: 6
Joined: Tue Aug 12, 2008 8:38 pm

Re: no image appearing . . test step wedge complete flop! help!

Post by zynthesis »

If none of your screens are washing out when you are spraying it, then it's allready cured. and your image area is cured also. Only two things are happening, the screens are curing before your exposer, or they are being over exposed. Nothing else to it. Or........ You didn't mix your photo activater with your emulsion?
jtannerc
Just Browsing
Just Browsing
Posts: 4
Joined: Sat Sep 06, 2008 10:08 pm

Re: no image appearing . . test step wedge complete flop! help!

Post by jtannerc »

Hi everyone... i am glad i found this post... I am having the same issue with the screen not washing out. I also am exposing inside with a safe light and then running just outside of my garage (in the sun) to wash out and nothing washes out.
I was wondering about the sun being able to expose it in that small amount of time. But i will try wetting the screen before I go outside.
Is there any way that heat could be setting the emulsion. It has been in the 90's lately and in my garage it could be around 100... can this be an issue? I do coat the screens and then get them into a large box and put a fan on it.

Thanks

J
--
j. tanner
biancaTanner designs
http://www.biancatanner.com
User avatar
d fleming
Moderator
Moderator
Posts: 546
Joined: Mon Apr 03, 2006 3:33 pm

Re: no image appearing . . test step wedge complete flop! help!

Post by d fleming »

can this be an issue?

sure can. heat and light are two of the biggest things to kill photographic emulsions. age after activation is next.
same basic question as previous poster who did not answer. what kind of light bulb are you using?
jtannerc
Just Browsing
Just Browsing
Posts: 4
Joined: Sat Sep 06, 2008 10:08 pm

Re: no image appearing . . test step wedge complete flop! help!

Post by jtannerc »

my safe light is a standard home depot type yellow bug light. I am using a Ranar exposing unit.

I thought the heat would or could be an issue. -- thanks
--
j. tanner
biancaTanner designs
http://www.biancatanner.com
Post Reply