# 2 coats of emulsion



## tkster95 (Aug 11, 2011)

I think I may be coating my screens with emulsion wrong. I saw an instructional video that said to coat both sides of screens starting with shirt side, using sharp side of coater, and enough pressure to hear a zip as you pass coater along screen. After allowing first coat to dry completely repeating the process a second time. 

Is that wrong?


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## rbforrest (Mar 20, 2010)

I think some people do it that way. We coat the print side, then the ink side, wipe the excess off the ink side, then lastly wipe the excess off the print side. 

I've heard of some printers double coating their white screens so they hold a larger deposit of white. Never tried it because white doesn't give me too much trouble.


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## Celtic (Feb 19, 2008)

Yes, you always want to start with the shirt side.
I do that (with the sharp side of the scoop coater), then coat the ink side, thoroughly dry(24hrs is good) horizontially, ink side down.


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## tpitman (Jul 30, 2007)

You want to get enough emulsion on the mesh so when it's dry it'll form a good "gasket" against the shirt (or whatever you're printing on).
I usually do two wet passes on the shirt side, flip it over, and do two wet passes on the squeegie side, then dry the screen shirt side down to let the bulk of the emulsion settle on the shirt side.
Another recommended way is to coat the shirt side with as many wet passes as it takes to get the squeegie side to glisten with emulsion, then flip it over and make one pass on the squeegie side.
I never scrape off excess. There isn't any excess. You want the emulsion to cover the texture of the mesh. As the emulsion dries, it'll shrink somewhat. A too-thin coat will often reveal a saw-tooth edge in the stencil, especially on curves in your art, especially on lower mesh counts. You want enough emulsion so that the edge of the art is defined by the emulsion, not by the mesh, as much as possible.


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## tkster95 (Aug 11, 2011)

Does anyone let the screens dry before applying a second coat, or does everyone apply the second coat wet?


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## Single Fin (Nov 15, 2007)

You would have to let it dry before putting a second coat if you need it. I have never put a second coat. I do have a small heater and fan in my dry box to help dry it faster and less drips. You wouldn't put two coat if there are fine lines in your art.


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## PhilR (May 3, 2011)

I would never apply a coat over a previously dried coat. I do it the same way as tpitman; 1 coat shirt side, 2 coats squeegee side. Except for high mesh counts for halftone work, then I'll just just use 2 coats.


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## ScreenFoo (Aug 9, 2011)

There are people putting on one coat with the sharp side, there are people putting seven or eight coats on with the dull side. 

IMHO It's only "wrong" if it's making problems for you.


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## Single Fin (Nov 15, 2007)

Are people confusing strokes for coats? I'll "stroke" each side twice but won't put a coat, let it dry, and put another coat.


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## ScreenFoo (Aug 9, 2011)

I guess when I read or talk about coating I think of a "coat" as one stroke. If you coat 2/2, you coat or stroke the "scoop coater" twice on the shirt side, twice on the squeegee side. If you are coating over a previously dried coat/set of coats/stencil, it's called "face coating", and is usually done with the sharp side to smooth out the stencil--the screen is then dried print side up. Face coating with the dull side is not a good idea IMHO. (I'd be interested in hearing if it works for someone, and under what circumstances)

Although I face coat on a regular basis, I catch crap for it on a regular basis too, so I can't recommend it to anyone.


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## Single Fin (Nov 15, 2007)

I'm probably not using the right terminology, being self taught, but just wanted to make sure everyone is on the same page. Thanks for clearing that up.


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## printing40years (Dec 27, 2008)

Do what works for you consistently. Experiment a little. Make sure the stroke is slow and with even pressure. Purchase a proper coater that is about two inches smaller in length than the inside width of the screen. Select an emulsion with high solids 35-50% so that you get good dots and sharp fine lines. I like a light colored one that allows me to see through it for easy registration on press. The emulsion will last longer if left in an air conditioned room or even in the refridgerator. Keep the lid on tight. Stir it well. The major manufacturers off the top of my head are: Autotype, Ulano, Fujifilm, Chromaline, Kiwo. You can download the tech data sheets off their websites. You can call their 800#s with questions and you can ask where the closest distributor is located.


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## tpitman (Jul 30, 2007)

The face coating ScreenFoo refers to is generally done to build up a thicker stencil than can be done with wet on wet coating. One of the benefits, even with just one face coat, dried shirt side up, is it makes a much smoother stencil against the shirt and tends to hold sharper edges. People who print the 3D stuff use it to build a thick stencil.
I've tried it a couple of times, but always had trouble getting an even coat. The coater tends to drag on the previous coat of emulsion.


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## screeningdude (Nov 15, 2011)

Are you kidding . ink side down??


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## tpitman (Jul 30, 2007)

screeningdude said:


> Are you kidding . ink side down??


With a face coat on dry emulsion, you want to dry the face coat on the shirt side with the shirt side up so the emulsion will level out over the existing emulsion.


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## alan802 (Mar 24, 2008)

I can't believe so many people coat with the sharp edge of the coater. I'm not saying all those who do it are wrong in doing so, but I do know for a fact that it takes more work to build a sufficient stencil with the sharp edge versus the round edge. I'd also be willing to bet that probably 90% (more like 99%, I'm trying to be nice) of the stencils made with the sharp edge do not have a sufficient stencil or what is considered by industry pros to be enough emulsion over mesh (EOM) for most textile work. I could be wrong but it seems like everything I've ever read on emulsion manufacturers' websites advises to use the round edge of the coater for textile emulsions. I do know that all of industry gurus that I read on a regular basis and "most" of the respected printers who participate on forums use the round edge. So that leads me to the question...why do so many people use the sharp side? How did this technique gain traction since it's actually not recommended by so many who are in the know? Now this will lead to many more questions like what actually is a sufficient EOM and how much emulsion is enough but I've already hacked this thread enough.


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## PhilR (May 3, 2011)

My scoop coaters don't _have_ a round side.


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## starchild (Jul 22, 2009)

alan802 said:


> I can't believe so many people coat with the sharp edge of the coater. I'm not saying all those who do it are wrong in doing so, but I do know for a fact that it takes more work to build a sufficient stencil with the sharp edge versus the round edge. I'd also be willing to bet that probably 90% (more like 99%, I'm trying to be nice) of the stencils made with the sharp edge do not have a sufficient stencil or what is considered by industry pros to be enough emulsion over mesh (EOM) for most textile work. I could be wrong but it seems like everything I've ever read on emulsion manufacturers' websites advises to use the round edge of the coater for textile emulsions. I do know that all of industry gurus that I read on a regular basis and "most" of the respected printers who participate on forums use the round edge. So that leads me to the question...why do so many people use the sharp side? How did this technique gain traction since it's actually not recommended by so many who are in the know? Now this will lead to many more questions like what actually is a sufficient EOM and how much emulsion is enough but I've already hacked this thread enough.


And because the sharp edge was "invented" to put down less emulsion (only used for face coating-smoothness & minor increment EOM buildup) it actually jitters along the mesh knuckles if you start coating with the sharp side and complicates the smoothness you are trying to achieve in the first place.


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## ScreenFoo (Aug 9, 2011)

alan802 said:


> I can't believe so many people coat with the sharp edge of the coater. I'm not saying all those who do it are wrong in doing so, but I do know for a fact that it takes more work to build a sufficient stencil with the sharp edge versus the round edge. I'd also be willing to bet that probably 90% (more like 99%, I'm trying to be nice) of the stencils made with the sharp edge do not have a sufficient stencil or what is considered by industry pros to be enough emulsion over mesh (EOM) for most textile work. I could be wrong but it seems like everything I've ever read on emulsion manufacturers' websites advises to use the round edge of the coater for textile emulsions. I do know that all of industry gurus that I read on a regular basis and "most" of the respected printers who participate on forums use the round edge. So that leads me to the question...why do so many people use the sharp side? How did this technique gain traction since it's actually not recommended by so many who are in the know? Now this will lead to many more questions like what actually is a sufficient EOM and how much emulsion is enough but I've already hacked this thread enough.



I think a lot of the people using the sharp side or putting down a very thin stencil are using poor or horrible exposure equipment. If you're already burning a 125 for an hour, putting two to four more coats on wet will increase that by what, maybe 50%? I can't slight people on this, I've been there.
I think the mindset that good enough is good enough is most of the reason though. It worked last week, why change it this week. I know that's what I'm usually up against when I try to change something process-oriented for the better. 

That being said, I'm not quite doing what Tom mentioned, as in building up EOM with face coats. I used to work with a kid that did that, and although he could get a thick stencil, it was a mess and a PITA. I'd think most people use cap film if you're doing HD. (Or are thick-stencil masters like Alan) Anyway, my point with facecoating with the sharp edge is *keeping* a thin stencil but smoothing the print side. I think some of Kiwo's stuff mentions a sharp edge facecoat as adding less than a micron to the stencil thickness--the point being, build up your desired EOM in your first coating, if it's too rough after it dries at your desired EOM, face coat it.


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## drscotty14 (Mar 23, 2011)

would it be better to accelerate dry time after coating?? seems if it sits wet longer it will all run the the shirt side more.


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## sben763 (May 17, 2009)

When I make a thick stencil. I do a 1/1 with a standard coater. Then I use a monster coater that has adjustable end caps. The second time around dry shirt side up. Can easily make a 50 micron stencil. I have a dry box @ about 90F. Although I have never done so the developer of the monster coater suggest using a hair dryer to skin the edges or the stencil so it doesn't run.


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## Ripcord (Sep 2, 2006)

I use two strokes on the shirt side and then as many as necessary on the ink side to produce that wet shiny look (on the shirt side) On a new screen usually 2/2 is fine, but as the screen is reclaimed over and over it becomes more difficult to lay down a nice layer of emulsion (I don't know why...) but on screens I've been using for awhile I often do 4-5 strokes on the ink side to achieve that shiny look.

I'm in Colorado and with our low humidity I'm able to dry the screens in an upright position with a fan in about 15 minutes. Since the emulsion dries so quickly there's no distortion due to the upright position.


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## Designfp3 (Jul 14, 2013)

is there any certain method of determining proper time to dry emulsion once screen coated placed in dryer shirt side down?


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## Single Fin (Nov 15, 2007)

I use a small room heater and fan in my dry box.


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