Trouble with exposure & washout

Here you can discuss issues related to exposing screens for screen printing. This includes determining the exposure, light sources and washing out the stencil in the washout booth. Emulsion issues may also be addressed here.

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thegarden
Posts: 1
Joined: Thu Aug 18, 2016 11:17 pm

Trouble with exposure & washout

Post by thegarden »

I'm trying to expose a design that is fairly simple and has washed out fine when I've used it in the past. For some reason now when I've been trying to get it on my screen it just isn't exposing or washing out right and I'm not entirely sure why.

This is the design I'm using
IMG_8590.jpg


This is what its supposed to look like (lines at the top of the design)
IMG_8591.jpg
But this is what has been happening when I've been exposing it now
IMG_8592.jpg
IMG_8589.jpg
I've been troubleshooting by changing exposure times, by letting the emulsion cure for longer, getting new emulsion (the one I was using was getting a bit old) and I put a new light in the lamp I'm using for exposing it and this is still happening. I'm using the exact same set-up and all the same materials I used when the design washed out perfectly before so I'm at a bit of a loss for what to do.

I've been looking online for what to do and haven't really found any solid answers so any ideas or help is much appreciated!
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Catspit Productions
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Joined: Wed Mar 21, 2012 10:47 am
Location: Phoenix, Arizona

Re: Trouble with exposure & washout

Post by Catspit Productions »

Given that you are using all the same materials as used before when you successfully made the screen, this will be very difficult to diagnose from afar. However it sounds and looks like you may be experiencing an underexposure. I would try adding a little bit more exposure time and work fast in the washout booth. As soon as the design rinses out to your satisfaction you need to stop.

https://www.youtube.com/watch?v=sLBCzcnQxEg

This video may also help:




Unfortunately this is one of those things that may require a bit of trial and error to remedy. Make sure the distance between the exposure light source and the screen is the same as you used before and also check that your film positive is very dense and dark.

I hope this helps out some. Good luck and let me know if you have further questions.
Jonathan Monaco
Catspit Productions, LLC
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http://catspitscreenprintsupply.com/
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