Exposure unit HELP

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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Arns
Screen Trooper
Posts: 5
Joined: Thu Sep 03, 2015 5:53 am

Exposure unit HELP

Post by Arns »

Hello ..... Can someone please tell me if I can use my Masterlite 1200 for exposure unit ? I have posted this on several forums and noone never replied dont know why ? Im using this light occasionally for photography.I also dont know nothing about lights and bulbs for screen exposing because I have worked only with stencils. Now I will try also to do with emulsion and have this at home and it seems to me it unnecessary to purchase a new light if this one can be useful.

Any information will be really helpful ......what distance and exposing time for 20x24 screens :)

Here is a photo what this light looks like and here are specifications.

Lamps 6x80 Watts, 5,600 K
Illumination Surface 35 x 54 cm ( 13,77" x 21,25" )
Dimensions 40 x63 x 7 cm (15,74" x 24,8" x 2,75" )

Image
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Catspit Productions
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Location: Phoenix, Arizona

Re: Exposure unit HELP

Post by Catspit Productions »

This all depends on whether or not the bulbs put out a good enough amount of UV light. Emulsion is only responsive to UV light so the lower the UV output the longer the exposure is. Unfortunately the only way to find out would be to try to expose a few screens with it. But the distance you will have to figure out through test exposures. The closer the screen is to the light the stronger the UV will be. The farther away it is the more fall off you will have. I would start with the light as close the screen as possible while still allowing the light to fully cover the 20x24 screen.

http://www.catspitproductionsllc.com/li ... sions.html

http://www.catspitproductionsllc.com/em ... gtips.html

http://www.catspitproductionsllc.com/emulsiontips.html

Those articles might help you to better understand direct liquid emulsions. These are the lights we normally use to expose screens:

http://catspitscreenprintsupply.com/1-p ... ack-lamps/

http://catspitscreenprintsupply.com/sma ... cal-items/

I hope that helps out some.
Jonathan Monaco
Catspit Productions, LLC
Learn how to screen print tee shirts!

http://catspitscreenprintsupply.com/
http://www.youtube.com/user/CatspitProductions
Arns
Screen Trooper
Posts: 5
Joined: Thu Sep 03, 2015 5:53 am

Re: Exposure unit HELP

Post by Arns »

Thank you for reply and instructions :) I have decided that would be better to buy a 500w halogen lamp for start because there are tons of tutorials on the net how to do with that even here I think. This Masterlite will try only for experiment someday because I dont know where to start even with test exposure rates which could be for example from 10sec to a couple of minutes I dont know, but whey this will be done I will update this posts here.

Thanks again :)
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Catspit Productions
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Posts: 1995
Joined: Wed Mar 21, 2012 10:47 am
Location: Phoenix, Arizona

Re: Exposure unit HELP

Post by Catspit Productions »

You're very welcome.

That's probably a good idea. When you get more familiar with the process experimentation will be much easier ;)
Jonathan Monaco
Catspit Productions, LLC
Learn how to screen print tee shirts!

http://catspitscreenprintsupply.com/
http://www.youtube.com/user/CatspitProductions
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