# Drying techniques of exposed, washed out screens



## galmiklos (Mar 30, 2011)

It may sound silly what I am about to ask, but was curious how others do it, especially that I am quite new to screen printing, although I have already printed a few things succesfully.

So, the question, how do you guys dry your screen, after it was exposed, and washed out.

And here's why I am asking it.

At first, I was just using paper towel to wipe out the water, then further dry it with hair drier. But the paper towel left a few lints here and there, and with high detail of the tiny water slide decals I was printing even that could ruin the day. Also, I had a bad feeling about wiping, since the squeegee side was never perfectly exposed, just barely, so I could always see some blu marks on the paper towel I was wiping with. By wiping I could actually transfer emulsion back to places that it does not belong to. You may say expose it better, but then I would loose some detail because of undercut.

I have also tried newsprint paper, and not wiping, but just laying it on top of the mesh, and pressing gently down with my fingers and palm. Of course, there was no lint, but when I pulled the paper off the screen, it actually pulled out some of the dots. Oh, I forgot to mention, I am printing halftone, 45 lpi on 230 mesh.

I was also thinking about just letting it drip, and dry itself. Would that work? I haven't tried it yet, maybe it's just my being overly paranoid, but I always thought the mineral content of the water is high enough, so that it could actually block the tiny holes.

I am open for suggestions.

Thank you in advance for all the advice,
Miki.


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## galmiklos (Mar 30, 2011)

Just wanted to bring it on the top, my posting was delayed due administrative reasons.

All your comments are appreciated, thank you in advance.


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## PositiveDave (Dec 1, 2008)

Dry it flat otherwise you may get emulsion clogging the open areas.
Sounds like you may be under-exposed, have you done an exposure test?


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## Rexx (Aug 13, 2009)

i dab mine with news print and throw it back on the exposure unit for a little bit


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## jwpintn (Dec 14, 2010)

Well ,I use a vacuum cleaner in a reverse setting to blow the water out,also dries the screens pretty quick.I use a filter queen vacuum.we have a vacuum repair shop next to us got it for pretty cheap.this has worked nicely for years,used on everything form fine detail process screens with very fine halftones to spot color jobs.just hold the screen up to a light source I usually just hold it up to the fluorescents on the ceiling and with a crevice tool attached blow form opposite the squeegee side until you chase all the water out,also you can dry your sceens faster this way,and I never have to worry about any emulsion or haze like stuff drying in your screen. I used to work for a major sports apparel place whom shall remain nameless,but they used shop vac,with a special tool they had attached to it to suck the water out.was pretty cool,the tool had a rubber piece on it and you went in a downward motion so not to damage the screen.and yes be sure your screens are fully exposed,


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## galmiklos (Mar 30, 2011)

Thank you very much for all the advice!

I know I barely expose my screens. I did an exposure test with the 21 step exposure guide, and I keep my exposure right at the edge on purpose. I probably should just use my 1000W halogen light instead of the "fancy" exposure unit I built with fluorescent tubes. For halftone, there is too much undercut, because of the many tubes. Or maybe it's the lack of vacuum - I just press the screen to the unit with a 3/4 MDF covered with a 4mm black neoprene, and a few boxes of 45 ACP bullets on top.

I like the vacuum idea a lot, although my vacuum is not reversible. I'll probably try with my hair drier, it's got cold/warm/hot setting, I can start with cold to blow the water away, then continue with warm to dry it further.


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## jwpintn (Dec 14, 2010)

It works great,if there is a vacuum shop in your area check them out,tell them what you need and they can probably get what you want,also if your handy they may have something you can buy really cheap and fix yourself,I like filter queens they are great,but there are other vacs that have this feature and are a little cheaper,but the crevice(the skinny looking tool that allows you to get to cracks and small areas with your vac) tool is a must,it really concentrates the air flow to force the water out of the screen.


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## galmiklos (Mar 30, 2011)

I have an airbrush compressor, feisty little machine, can do about 30 psi. Perhaps, that will do. If all else fails, I will surely fall back to the reversible vacuum. I just want to try everything I got, before I invest in "another useless gadget" (guess who I quoted ;-)


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## tmathis (Dec 27, 2010)

I put my damp screens on the press, wipe each side with a clean squeegee, then put my 24'' fan in front of them. between the squeegee taking off most of the water and the airflow from the fan they dry pretty quickly.


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## just90 (May 1, 2007)

I have been screen printing for only a few months, so I'm not a pro by any means. However, I use quick dabs with newsprint on both sides of the screen to remove the water on the surface, place it on a homemade rack shirt side down, & put a fan in front of it on low.


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## poker (May 27, 2009)

I dab with newspaper then put it in front of a fan....."set it then forget it." it's not the fastest but if you plan well, you'll have shirts done the same day (or night in my case).


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## foot print (Jun 2, 2010)

I dab with a paper towel drying around the edges of the frame then put in my drying cabinet with a small space heater...or on a nice HOT sunny day I let mother nature help out. So just in case you are under exposed the sun will take care of that


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## superD70 (Dec 22, 2010)

I give em a good shake then hit with compressed air then set em in the sun for a few min.


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## jwpintn (Dec 14, 2010)

was thinking about it and mabey you could tape the crevis tool on to your hair dryer,that might concetrate the air enough,it still will not be the same,but it might give you a feel for what I'm talking about,I'd be a little weary about hitting them with to much air.


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## tpitman (Jul 30, 2007)

I remove most of the water with a cheap windshield squeegie, blot with paper towels, and if the sun's out, let 'em bake a half hour or so. I've also used a shop vac with a hard surface nozzle with rubber blades, which works very well. I would never blow air against a wet screen for fear of blowing dust onto the relatively soft emulsion. For that matter, I wouldn't blow air against a dry screen. Just an opportunity to get lint embedded.


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## jwpintn (Dec 14, 2010)

been using this method for years,never had a problem,might not work for everybody,but like I said used this on everything from process screens to spot color.my screens turn out beautifully.and sometimes I'll go ahead and dry them all the way to get them on the press.And actually the 1st shop I used to work for is where I learned this process.we were a vendor for a world wide huge manufacture,we were one of 2 vendors,and we make about 70 screens a week for them.one of our screens was on record as to having ran over 56,000 some odd prints(we out preformed the other vendor),and every screen we blew the water out,everyone is different and I guess you really just need to find what works best for you,but using this technique has saved us time and we've gotten jobs on the press in no time flat.But just do things that work for you,and things you feel comfortable doing.That's just a little secret of how we do things and it works great for us,halftones ect.


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## galmiklos (Mar 30, 2011)

I tried my airbrush compressor, not a chance... The pressure may be enough, but the volume is nowhere near.

With the hairdryer, I can see how your process could work, just need a little more pressure, and/or that nozzle you mention to make a wider, higher pressure air flow. I guess I will just have to find the right pressure, distance, nozzle, etc.

Thanks a lot Wes!


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## Hiway (Apr 8, 2011)

If your dots are getting knocked out, and there is that much unexposed emulsion it drips or hazes, then you are underexposing... especially on a 230 mesh.

I try to explain to most folks- it isn't the mesh that holds the dot in as much as it is the emulsion and proper screen prep that allows for that.

A heavier deposit on the underside of the screen will create a capillary film type screen if coated and dried properly (coat inside, then underside, then scrape inside. Let dry- then 1 steady smooth coat to the underside. Always dry horizontal with underside down.)

I hold 47 line on a 156 no problem- I can get it to hold on a 110 also. Down to about 10% and even 5% on a good dry day. The key is exposure with proper lighting- most exposure units are not up to the task. Light intensity is key. The screens wash out in a few seconds, and with no newspaper blotting or air compressor (I used to use both in the past religiously) I can set the screen aside and then post in the sun as has already been mentioned. I use emulsion as a blockout, and then repost. I need my screens to stay solid for up to and over 1000 to 2000 piece runs. 

They do.


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## LeftKoast (Apr 9, 2011)

I lay out some news paper first. Lay the screen down (exposure side down). Then I lay another sheet of newspaper down on the ink side and lightly press it in. pull paper out and stand screen let a fan blow dry. I've also use the news paper method and let it sit in sun for secondary exposure.


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