# I'm having trouble figuring out why I'm blowing out my image when I�m washing out my screen



## CMcGruff (Feb 4, 2011)

*I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

I’m fairly new to screen printing and I’m having some issues while I’m washing out my screens after burning them. I’m trying to screen print the size tags for my t-shirts and I keep blowing out my image and I’m not sure if I’m under/over exposing, if my films aren’t dark enough, is my font too small, should I use a 156 screen, did I not coat the screens enough times?? I know it could be many different thing depending on my variables so I’ll try and give as much info as I can.


My room is light safe and it’s 65°F and 45% humidity
I’m using 20”x24” wood screens with 110 mesh
I’m using CCI DXP Diazo-Photopolymer Dual Cure Direct Emulsion
I’m using brand new emulsion that was mixed 3 days ago and allowed to sit for 6 hours so the air bubbles can escape
I coated the screens with emulsion once on both sides, let them dry with the shirt side down overnight; coated the shirt side once more and dried overnight 
printed on R Laser Film 8.5”x14" and then sprayed with SprayWay Toner Aid Enhancer (I had to tape 2 on top of each other because the image wasn’t dark enough) 
I’m using Ryonet’s 25”x36" SE Digital Screen Exposure Unit
foam is placed on the inside of the screen, with a piece of wood on top and then 60 lbs weights on top of that
 
I wash out my screens using a 1500 PSI power washer


The 1st screen I exposed for exactly 4 minutes and after I washed out the screen and blew out the image, I checked the step wedge image on the screen. According to the instructions, I should double the exposure time on the next screen.

The 2nd screen I exposed for exactly 8 minutes and it came out almost perfect. The only area the did blow out was very small.

This is where I’m at right now and I’m not sure what I should try next.... I’d appreciate any suggestions!!


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## firehouse1979 (Feb 5, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

Looks like your on the right track. Could just be your exposure time. I know any time we had problems with blow outs it was due to the lack of exposure time.


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## n.signia (Nov 21, 2007)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

I would increase your exposure time.


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## n.signia (Nov 21, 2007)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

Although 8 minutes seems rather long exposure time for the set up your running. I wonder if you have a bad batch of emulsion.


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## Geraldine64 (Feb 3, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

I take it what you can't blow out is the small type. Are you working the power sprayer so close that you're blowing out the image? I use 2 fingers one on the shirt side and one on the ink side. Start off gently rubbing on the type and increase if it's not bulging. 

I'm not familiar with your exposure unit. But I know if you're not getting a tight contact and your light is scattering, you'll always have trouble blowing out the small type because the light is exposing around the edges of the typeand you don't have crisp edges.


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## foot print (Jun 2, 2010)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

try using a garden hose with a attachment. and if it has the mist setting use it...I only use my power washer to reclaim my screens. If you are having to use a power washer to wash out/ blow out the image you might be over exposing.


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## n.signia (Nov 21, 2007)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

you say your using wood screens, are they warped? lay them on the exposure glass, they should be perfectly flat with no wobble. if you have a warped screen, and not enough weight to ensure the section of mesh that is off the glass is pressed firmly agains the glass while exposing, the light will undercut the film, and expose the section, making it very hard to washout (or impossible) which would eventually breakdown and blowout with excessive use of the pressure washer.

all that to say, if your screen is warped, try increasing the weight on the screen so it touches the glass on all sections of the image.


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## Geraldine64 (Feb 3, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

Ii agree with n.signa. You've got a tiny gap probably caused by a wrapped screen. I don't think more weight is going to do it if the screen is warped because didn't you say you've got 65 lb. on it now
or did I read that wrong.


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## vai (Dec 24, 2009)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

I also use Ryonet's CCI Dual Cure Emulsion and Ryonet's exposure unit. I was having trouble with exposure time in the beginning, so I called Ryonet and they told me approximately 12 minutes is the correct exposure time. 12 minutes works for me now. After you're finished exposing the image, you should run tap water over the screen on both sides and let it sit for about a minute- this loosens up the emulsion. Then I just use my kitchen sprayer to wash out the screen. The image washes out in a minute or two (sometimes I need to rub my finger over stubborn spots). I suspect your water pressure is too high plus your exposure time is not long enough and that's why your image is blowing out.

Good luck.


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## K Chez (Jun 11, 2008)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*



My room is light safe and it’s 65°F and 45% humidity
I’m using 20”x24” wood screens with 110 mesh
I’m using CCI DXP Diazo-Photopolymer Dual Cure Direct Emulsion
I’m using brand new emulsion that was mixed 3 days ago and allowed to sit for 6 hours so the air bubbles can escape
I coated the screens with emulsion once on both sides, let them dry with the shirt side down overnight; coated the shirt side once more and dried overnight 
printed on R Laser Film 8.5”x14" and then sprayed with SprayWay Toner Aid Enhancer (I had to tape 2 on top of each other because the image wasn’t dark enough) 
I’m using Ryonet’s 25”x36" SE Digital Screen Exposure Unit
foam is placed on the inside of the screen, with a piece of wood on top and then 60 lbs weights on top of that
 
I wash out my screens using a 1500 PSI power washer

 Sounds like a combination of several things; too thick of a stencil, underexposure and too much pressure on developing. When developing a screen, you should just wet both sides first, let it sit for a minute or two and then spray the shirt side with a garden hose or similar type gentle spray-it should wash out with minimal effort. If not, then you're probably over exposing.


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## CMcGruff (Feb 4, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

I appreciate all the responses, they definitely helped!

I checked the wood frame that I used and it wasn't warped, but when I checked my other wood frames I did find 1 that was a little warped. I haven't used the frames that many times and I use a screen holder to keep the screens out of the water so I was surprised to see it was already warped. I think from now on, I will be purchasing aluminum frames. 

The next thing I did was change my exposure time to 12 minutes and use a garden hose set to the flat setting and that did the trick. I was really surprised that I needed to increase my exposure time to 12 minutes, especially because the instructions for the exposure unit said it would take 4 minutes. Do you think the exposure time had to be increased to 12 minutes because I coated the screen 3 times (4 min a coat x 3 coats)? Also, I'm not sure if I'm reading the exposure strip correctly. When I exposed the screen for 12 minutes, if I'm reading it correctly, I was left with 10 steps, but shouldn't I be closer to 7 steps??


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## Geraldine64 (Feb 3, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

Chuck, since you and VAL have the same exposure unit, she might be the most helpful. As a rule of thumb, 2 coats on the shirt side and 1 cost in the ink side should be enough emulsion and I do this in one time frame. I don't wait for the first coat to dry. When I'm printing less than 250 that's good enough. Assuming your housekeeping is good and it's not dusty or such to cause pin holes. When I use a glitter screen at 40 mesh I do this procedure 4 separate times so I get a thick layer of emulsion which will give a better look to the glitter. Dry overnight each coating time. The thicker the emulsion the heavier the print. 

I'm glad you got a fix. Screenprinting is a journey of solving problems and learning. You never know it all. This forum is really nice because people looking for answers can ask questions and you receive answers from fellow printers. I just joined less than a week ago asking about DTG printers but I've been screen printing for over 30 years and enjoy helping other fellow printers.


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## vai (Dec 24, 2009)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

I coat the screens only once on each side so I don't think the increased exposure time is due to coating 3 times. I asked Ryonet why it took so long also, they told me that different emulsions take shorter or longer to expose. I used to use a different emulsion before Ryonet's and that one only took 7 minutes to expose.

I've never tried the exposure strip so can't comment on that.


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## kc6789 (Mar 28, 2010)

Ryonet's new hifi emulsion. Coated one time on the shirt side. 1-4 minute exposures. Washes out under low water pressure. Crazy thick and crisp stencils. Woo!


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## CMcGruff (Feb 4, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*



kc6789 said:


> Ryonet's new hifi emulsion. Coated one time on the shirt side. 1-4 minute exposures. Washes out under low water pressure. Crazy thick and crisp stencils. Woo!


I'm going to have to try the hifi emulsion. I wanted to try it out when they had that sale on them, but I've only used the emulsion that needs to be sensitized and wasn't sure how long the hifi emulsion would last.


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## foot print (Jun 2, 2010)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

TextilPV is the best emulsion I have used and still use exposes super fast and has long shelf life.


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## Bob Wellen (Jan 25, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

My name is Bob Wellen> I am the technical manager at Murakami> 800.562.3534 EXT:111. I CAN SOLVE YOUR PROBLEMS.


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## brice (Mar 10, 2010)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

I was using the same emulsion and an exposure unit from Ryonet and exposing 4 - 4:15. 12 minutes seems crazy.


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## Bob Wellen (Jan 25, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

How old are the bulbs in the unit? It is the amount useable light. The wave length is 380 to 410 nanometers. If the bulbs go very far below that the emulsion will not expose. Also, check to make sure positive is black. I mean black and dense. If it is not, then the light may go through when the exposure is pushed upe pos up to light and you will have trouble washing out the image. Hold the pos up to light to see if it is at all transparent. If it is then use some toner enhancer to blacked the image.

Bob


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## CMcGruff (Feb 4, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*



brice said:


> I was using the same emulsion and an exposure unit from Ryonet and exposing 4 - 4:15. 12 minutes seems crazy.


I was thinking the same thing especially since I was exposing for 15 minutes using a 500 watt halogen light with Ryonet's screen exposure stand. I think I'm going to contact Ryonet and see what they say.


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## Bob Wellen (Jan 25, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

You can also call me at 800.562.3534 Ext:111. I would be happy to help anyway that I can.


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## CMcGruff (Feb 4, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*



Bob Wellen said:


> How old are the bulbs in the unit? It is the amount useable light. The wave length is 380 to 410 nanometers. If the bulbs go very far below that the emulsion will not expose.


I purchased the exposure unit the last week of December 2010, so I'm assuming the bulbs are new. How do I measure the bulbs wave length?



Bob Wellen said:


> Also, check to make sure positive is black. I mean black and dense. If it is not, then the light may go through when the exposure is pushed upe pos up to light and you will have trouble washing out the image. Hold the pos up to light to see if it is at all transparent. If it is then use some toner enhancer to blacked the image.


I print my positive's using a HP LaserJet 1320 on R-Laser film. One film isn't dark enough, so I print 2 and spray them with SprayWay Toner Aid Enhancer. I just ordered an Epson 1400, hopefully after I order waterproof films and Blackmax ink that will rule out my positives not being dark enough.


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## Bob Wellen (Jan 25, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

Great. That all will help. the next step would be to purchase a new exposure system when funds are available.


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## dd2 (Sep 15, 2010)

You can get the 1400 at office depot, order dye ink and refillable cartridges on the internet, which will print like the black max. Get the water proof film and your positives will be positively amazing. Do your own research on this site, that is where I got my info. The feedback is that the black max refills are pricey.


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## edward1210 (Nov 7, 2009)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

fOR HOW LONG DO YOU EXPOSURE THIS EMULSION?


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## dd2 (Sep 15, 2010)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*



edward1210 said:


> fOR HOW LONG DO YOU EXPOSURE THIS EMULSION?


do a step wedge....


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## Ocamp (May 10, 2013)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

Hey CMcGruff,

I know I'm waaaaay behind on posting to this thread, but in case someone reads this for the same problem ...

I agree with Val (and the others are good ideas too). I am a total newbie and I had the exact problem. My solution was 3 fold

1) made thinner emulsion coats - only one pass / tight and quick
2) almost doubled my exposure time (with a heavy black backing to avoid light bleeding. 14 min
3) Lowered my water pressure A LOT. I will use a simple pump pesticide sprayer (cleaned of course). I use the garden hose, or a power washer for the reclaiming stage. 

I believe you are literally breaking the emulsion bonding with the force of the water. You just want to push out the soft, non exposed sections.

Good luck!


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## macparks (May 25, 2011)

*Re: I'm having trouble figuring out why I'm blowing out my image when I’m washing out my screen*

I run into the same issues, what it sounds like since you have the proper exposure unit is that your positive isn't positive enough! I find that if I try to burn a screen, it literally eats some of the black away?! I am printing on a laser printer, and overlapping 3 positives to get good results. When the screen is properly exposed, you should NOT have to use a pressure washer. A garden hose at medium spray is all you should need. If you are using a power washer, you aren't exposing the screens properly. Be sure that you dial that in to the 7th step on your scale. Then if it isn't washing out, your positive isn't black enough, or you are getting seepage around the edges (not getting positive contact)... Good luck, I hate the trial and error aspect especially when you are under the gun! Good luck.


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## mr86baby (Oct 17, 2014)

Just wanted to say thanks to everyone that put up recommendations here. Was having the same issues and tried using a lighter setting on the sprayer attached to my hose. And was finally able to get the image to come out great for anyone wanting to know I used the vertical setting as well followed my the mist setting to get any parts that needed extra attention.


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