# Emulsion too thick? Too thin?



## karolina (Oct 7, 2007)

Hi Guys - 

Just wondering what you experts have to say about emulsion thickness...  

I have a little trouble when applying the emulsion... It gets a little streaky and sometimes a bit uneven as well, but my main concern is that too much emulsion is applied. I use a "scooper" (filling it generously) and put the screen up against the wall on an angle, about four inches away. 

Does too much emulsion create printing problems? Problems with wash out? Any thoughts are greatly appreciated - Thanks!

Can't wait for the Johnny Cupcakes interview!!!


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## darwinchristian (Aug 24, 2007)

karolina said:


> I have a little trouble when applying the emulsion... It gets a little streaky and sometimes a bit uneven as well, but my main concern is that too much emulsion is applied. I use a "scooper" (filling it generously) and put the screen up against the wall on an angle, about four inches away.


the scoop coater I use has a dull and a sharp side for application. I always use the sharp side. with a clean edge and clean, settled emulsion the only thing you need is a bit of practice coating the screens. one solid swoop. you'll be a pro in no time. 



karolina said:


> Does too much emulsion create printing problems?


the emulsion on screen constitutes the thickness of the stencil. the thicker the stencil, the more ink a screen will hold/ dump after it's been flooded. in some cases a "built-up" stencil is needed. for instance printing glitter through a 30mesh. you need the extra emulsion to preserve your edge definition in the art. 

for general printing purposes you will want a thinner stencil. coat the print side, then the ink side. one good stroke. 

sharp side of scoopcoat= less emulsion down/ thinner stencil= less drying time= time and money saved.

hope this helps.


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## karolina (Oct 7, 2007)

Hi - Thank you so much! That is very helpful... 

Never noticed that the scooper has two different sides. Sounds like I need to use the thin one - I've only been able to apply thick coates, and it's driving me nuts! I then empty the scooper and run over the screen an additional time or two. This removes most of the excess emulsion (which is quite a lot), but leaves it streaky... 

I just returned from my backyard, where I was washing out the screen. Unfortunately, most of the emulsion peeled off (pressure washer method). I tried soaking the screen first (30 seconds), but it didn't make a huge difference. 

I guess I will have to wash off the emulsion and start over. Tried once, but the screen didn't get completely clean. I can still see shadows of the image, when I hold it up to the light, as well as bits of pink emulsion (outline of glass placed on image during exposure). Is the caused by bad washing, or bad product? 

Thanks again, I appreciate your advise!!! Have a great night - Karolina


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## darwinchristian (Aug 24, 2007)

karolina said:


> I then empty the scooper and run over the screen an additional time or two. This removes most of the excess emulsion (which is quite a lot), but leaves it streaky...


the streaks. i try to never bring the coater across the screen more than once per side because of this. i haven't had a chance to see if the streaks have a negative influence on the consistency of my stencil or not, but probably best to avoid. if the sharp side of your coater is still insufficient you will need to check your technique... on mine there are angle marks for the perfect coating angle. still problems? maybe check out a different scoop coater. i got mine from the ryonet corporation. (silkscreeningsupplies.com) 




karolina said:


> I just returned from my backyard, where I was washing out the screen. Unfortunately, most of the emulsion peeled off (pressure washer method). I tried soaking the screen first (30 seconds), but it didn't make a huge difference.


sounds like the emulsion either wasn't dry enough before exposure or the stencil was underexposed. definately affected by amount of emulsion on the screen. focus on coating the screens. when you are consistent, creating an exposure step test will give you more consistent data for exposure time. forum member Richard Greaves has covered emulsion, exposure and step tests at length all over the forums here. try searching some of his posts.



karolina said:


> I guess I will have to wash off the emulsion and start over.


again, and again, and again.



karolina said:


> I can still see shadows of the image, when I hold it up to the light, as well as bits of pink emulsion (outline of glass placed on image during exposure). Is the caused by bad washing, or bad product?


there is a chemical to remove the shadows. a viscous dehazer. nasty stuff but it works. talk to your supplier about a stain remover or dehazer. some people don't use it, because the shadows or stains don't typically affect the performance of the screen.

the emulsion should completely come out. that screen needs to be "clear" or it will create a whole bunch of problems you don't need. there's a chemical for that, too. get an emulsion remover and follow the specs. i'm pretty sure if you leave it on screen too long the emulsion will harden and ruin the screen. 

thank you, and have a good night as well.


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## rusty (Feb 9, 2007)

karolina said:


> I just returned from my backyard, where I was washing out the screen. Unfortunately, most of the emulsion peeled off (pressure washer method). I tried soaking the screen first (30 seconds), but it didn't make a huge difference.


You don't want to use high pressure to wash out your images. A pressure washer will easily blow out burned in emulsion that you do not want to wash out. I have actually reclaimed a screen with just a pressure washer before just to see if I could do it. It takes longer than using stencil remover, but it blew it out.

Just normal water pressure will be fine when washing out design. If you are using your garden hose outside, just use one of those pistol grip sprayers and experiment with which spray patterns works best.


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## rusty (Feb 9, 2007)

karolina said:


> I guess I will have to wash off the emulsion and start over. Tried once, but the screen didn't get completely clean. I can still see shadows of the image, when I hold it up to the light, as well as bits of pink emulsion (outline of glass placed on image during exposure). Is the caused by bad washing, or bad product?


Stencil remover and a pressure washer should easily get all of the emulsion out. UNLESS you let the stencil remover dry on it. That's a quick way to ruin a screen. Just spray with stencil remover and let it sit for about 60 seconds, but make sure it doesn't dry. Then scrub a little with a screen brush to work the stencil remover around into the stencil, and blow it out. It should come very clean.

If you have ink shadows, use some of the ink degradent on it and scrub it a little and then blow it out again, and they should clean up great. I've never needed to use any of that caustic dehazer stuff.


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## karolina (Oct 7, 2007)

Thanks so much guys, I really appreciate it... I've gone through three screens today. I'm exhaused and hope that tomorrow will bring better luck! I finally got a new press (4 color/single station from silkscreeningsupplies), but the pallet doesn't adjust/move very far... I suppose this means I will have to make another screen, this time exposing horizontally to make the screen shorter. Now that my image came out pretty nicely, I have to make another one simply because the pallet doesn't reach the image (center of pallet - 22 x 24 screen). This seems very strange to me... Perhaps it's time for bed - lol!

Any advise on this? Thanks again... Oh, and my scooper is from silkscreeningsupplies as well.


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## Orso (Aug 7, 2007)

It takes alittle practice to get the correct thickness with the emulsion. I just recently went through exactly what you are going through now. What I found that I was doing wrong was that I was not putting enough pressure again the screen when I was pulling up the coater. Now after about 10 or so attempts I have perfect coats. One pull on each side.


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## jayjude (Jan 20, 2008)

can i use a modified scoop coater like a fiber with thin edges? or like a plastic ruler for pressing the emulsion? which is better a thicker or thinner coating of emulsion? i really am new in this kind of projects and maybe u guyz can help me out. thanks


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## lakevillescrpper (Oct 17, 2019)

I have a Yudu machine that I used quite a bit when I first bought it 10? years ago when my daughters needed shirts for Irish Dance, Powderpuff Football and Senior year. Once they went off to college and since then I have not used the machine. My older daughter now needs cute shirts for a bachelorette party where she is maid of honor. I dug out the machine. Bought new liquid emulsion and new emulsion remover. I had some screens that still had the design burned into it and I cleaned them and yesterday I applied the emulsion to two screens. It took literally all day for them to dry in a combo of the Yudu and air drying, There are polka dots of emulsion on one of them and streaks on the second. I acknowledged that I had a re-learning curve since I haven't touched any of this for 6+ years, but I have memories of being very successful at applying a thin layer of emulsion to both sides of the screen with no streaks. Maybe I'm using different emulsion but I came to this forum to see about adding water to the emulsion. I have two scoops and I don't know that I've paid attention to the sharp versus not sharp edge. I'm going to try some different things before I give up. Thanks for the existence of this forum and I'll let you know how it all turns out.


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## davidjhn127 (Oct 15, 2019)

karolina said:


> Hi Guys -
> 
> Just wondering what you experts have to say about emulsion thickness...
> 
> ...


Emulsions become solid upon exposure. However, small pieces or flakes of emulsion can wash out after you prepare the screen for it. Hence, you need to inspect the surface carefully. While applying emulsion avoid uneven coating that results in uneven exposure. Thicker areas of emulsion won't dry up completely due to insufficient exposure, therefore will not adhere to the screen completely.
If you are facing such an issue, you have to re-paint/re-coat the entire screen. Before doing so, be sure that the screen mesh tension is adequately high and also make sure that your frame is sturdy enough.


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