# Burning the image to the screen



## Sophie (May 1, 2008)

Hi there,

I am new to Silk screen printing. I am using Speedball photo emulsion and I cannot burn my image to screen. I am using a UV light and nothing happens. I tried burning it for 45 mins, 30 mins, 25 mins, 20 mins, 15, mins, 13, 10, 5 mins, 2, 1 min and still no image on screen! Can someone please help me!!!! I really want to do silk screening!!!!!!! thanks!!!


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## Pwear (Mar 7, 2008)

*Re: Buring the image to screen*

Is it not washing out of the screen, or is the whole screen washing out without the image?


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## Sophie (May 1, 2008)

*Re: Buring the image to screen*

hi ! It doesnt wash out!! I dont know what I am doing wrong! Lastnight I burn it for 4 mins and it didnt wash out, and the other day I burnt for 1 min and it didnt wash out!


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## fdsales (Jul 1, 2007)

*Re: Buring the image to screen*

Are you handling your coated screens in a safelight environment, or just under room lights. If no emulsion washes out, then it's being over-exposed; possibility by surrounding lights, like flourcent, daylight coming thur a window, etc. Once you open the container of emulsion, it should be done in a room w/ a yellow or other safe light. Your coated screens should also be handled in the safe light area.
Another issue could the emulsion itself...was it a 2 part mix (where you add a powder mixed w/ water), or is it basically "ready to go"?


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## srdstudio (Mar 25, 2008)

*Re: Buring the image to screen*

I am having the same problem that sophie is having but i have done everything in a light safe envirnoment and my image still is not coming out. I have done previous screens with the same techniques but with less precautions and seemed to work fine. Now that I am taking precautions I am having problems. what am I doing wrong?


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## tman07 (Nov 14, 2007)

*Re: Buring the image to screen*

After you expose the screen, do you see the image at all on the emulsion?
Does anything at all wash out?

Does your film positive have good density?


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## Sophie (May 1, 2008)

*Re: Buring the image to screen*

hi there,


I dont see anything at all!


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## tman07 (Nov 14, 2007)

*Re: Buring the image to screen*

I'm not trying to insult your intelligence, but you sure you have the film positive between the light source and the screen? I'm sure you do, just grasping for straws now. The most common problem is underexposure due to poor light source. But to have nothing wash out means overexposure for some reason. Could the emulsion be old and past expiration date?
Even with poor density with you film positive, you should still get some image on the emulsion after exposure.


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## Matto (Sep 28, 2007)

*Re: Buring the image to screen*

I would almost bet your positives are not dark enough. The max time I use under a 1000 watt halogen is 15 minutes and my screens wash out good. If I go beyond that they start to get hard to blow out. You should not be able to see light through your positives when you hold them up to a lamp. Hope this helps.


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## darwinchristian (Aug 24, 2007)

*Re: Buring the image to screen*



fdsales said:


> was it a 2 part mix (where you add a powder mixed w/ water), or is it basically "ready to go"?


my bet is with Brian.

speedball emulsion isn't pre-sensitized. you know that little bottle that came with the kit that says: "do not throw away, this bottle is not empty"... that's your emulsion sensitizer. it'll turn the emulsion from blue to green when properly mixed, and give it photo-sensitive properties.


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## Sophie (May 1, 2008)

*Re: Buring the image to screen*

hi there,

I did mix the the little bottle and it did turn green, hmmmmm.....


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## darwinchristian (Aug 24, 2007)

*Re: Buring the image to screen*

okay.

to check the density of your positives, tape a coin to the screen, between the emulsion and the light source. this will block all uv energy and should wash out fine after near-proper exposure.

what kind of light source are you using? you need uv type a light to expose the emulsion. 

speedball emulsion is usually a diazo-type emulsion that will show image area before washout. can you see the image appearing lighter on the screen after exposure and before you put water on screen? after?

a quick search brings me this link: http://www.t-shirtforums.com/screen-printing/t26831.html#post158189 by Ulano's emulsion super-wizard Richard Greaves. it may have some helpful info.


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## Sophie (May 1, 2008)

*Re: Buring the image to screen*

Hi there,

I am using a UV light bulb. ( only one ) How long am I supposed to expose it for with a UV light?.


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## Sophie (May 1, 2008)

*Re: Buring the image to screen*

I dont see any image after washing the screen nothing changed at all after washing.

*Matto*- You said you used a 1000 watt halogan light. Can you put that in a normal light socket and where can you buy that?

I am using a UV light black light, Do I need a special type of light? 

What is the best light source to used while bruning the screen?

Youre suppose to apply a thin coat to your screen right? The first few types I apply photo emulsion on, I set it to dry and there are dripping marks. I guess the image cant burn through thick coat of emulsion? 
Now I am apply thin coat., maybe too thin??


It is like my 15-20+ times trying to burn the screen ...So difficult!! lol.


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## darwinchristian (Aug 24, 2007)

ummm... don't know what kind of bulb you have. photo-uv, 500 watt??? etc etc...

there is no way to determine how to correctly calculate exposure times without conducting an exposure test. a search for exposure test here brings up: T-Shirt Forums Search Results

a thread i found to contain some useful information can be found here: http://www.t-shirtforums.com/screen-printing/t11860.html

there may be someone out there with a guide for distance of light source to screen if you post the specs of your bulb...

good luck...

derek


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## Matto (Sep 28, 2007)

*Re: Buring the image to screen*



Sophie said:


> *Matto*- You said you used a 1000 watt halogan light. Can you put that in a normal light socket and where can you buy that?


I picked one up from lowes. It is the dual lamp in one fixture 600watt model that I retrofit to hold 2 500 watt halogen bulbs. my only caution with my setup is it gets hot so use a fan to keep the glass cool or it will break when you place it on the counter. Oh this light plugs into a regular outlet.
600-Watt Work Light


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## EasyTeesK (Nov 28, 2007)

Sophie,

I also purchased a Speedball kit when I started. I had no problems with coating, exposing, and washing out. My partner and I built an exposure unit using 6 UV bulbs (we tried both the plant bulbs [from Wal-Mart] and the unfiltered black light bulbs). These bulbs are the long, fluorescent ones, about 20" long or so. We placed these in a box about 6-8" from the glass. Our exposure time is approximately 5 minutes using pink dual-cure emulsion (not what came with the kit). Near perfection every time.

Again, not to insult your intelligence (since I was in the same place you are), but you should coat the screen with a thin film on the shirt side, then the squeegee side. Make sure you coat and dry the screen in a dark room. We use a yellow bug light. We built a small dryer. The screen should be dry within an hour or two. You can tell it's dry when you touch it and it doesn't feel tacky. Once it's dry, put your stencil on the shirt side backwards. When you look at it from the squeegee side, it should be readable. Tape the stencil and put the shirt/stencil side on the glass. It should be tight against the glass or the light will come through and expose at least the edges, if not the whole thing. The light should be shining onto the stencil. We also use toner enhancer on our stencils, as this makes the black on the stencil very dark. When you do wash it out, it shouldn't take much more than a garden hose with light pressure. We do ours outside, which we shouldn't, but it's only because we don't (yet) have a washout booth. Washout should only take a couple minutes.

We've done many experiments with emulsion and exposure times and washing out, etc, only because we had limited knowledge about screen printing at the time. I'm explaining to you what we've learned with our equipment setup. Exposure units come in all sorts of shapes and sizes. I learned in a video on the Internet that exposure time is a function of light source wattage and distance from the screen. My box was patterned after a professional setup. The plans were from the Internet (I forget exactly where I got them). Our box does not produce a lot of heat. As with the other posts, it sounds like you're not exposing it correctly (either time or position of the stencil).


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## God Father (Feb 27, 2008)

Screen Exposure Stand

Use this thing and expose for 12.5 minutes you'll have no problems.


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## Sophie (May 1, 2008)

Hi there,

I am using a 75 watt UV black light. Does anyone have any idea on how long I should expose? 


What is the best light to use?


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## aplusbowling (Dec 6, 2007)

Hi there...

As tman07 said, is your transparency with your image between your screen and light source? Again, not trying to insult your intelligence...just trying to understand your process.

Your transparency should be laying on your screen and the light source should shine down from above.

Where are you storing your screens to dry after you coat them? This needs to be in a light safe room. Any outside light that filters in will expose your screen before you can use it.

From what you have said though....it sounds like your screens are being exposed before you use them.


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## James R (May 3, 2008)

Auditor Clothing said:


> Screen Exposure Stand
> 
> Use this thing and expose for 12.5 minutes you'll have no problems.


Question are you using a piece of glass to hold down the film to the screen, also are you using white mesh.


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## darwinchristian (Aug 24, 2007)

Sophie said:


> I am using a 75 watt UV black light.


Is it an "unfiltered" uv blacklight? I'm pretty sure your Spencer's Gifts type black light bulbs filter the essential UV-A energy required to react with the emulsion. 

Not sure what the best light source is, you could obviously spend many many dollars on a single point mercury halide setup, but, asking someone at your local hardware store what they'd reccomend for a strong UV-A emitting bulb could yield some good results...


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## Sophie (May 1, 2008)

hi there,

yes i am using a glass to hold my screen and also i am using a white mesh that I bought from a studio store that is for silk screening.


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## Sophie (May 1, 2008)

Hi,

I even tried the coin thing and it still didnt work. hmmmm


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## aplusbowling (Dec 6, 2007)

Are you reclaiming the screen after each exposure test and re-coating? If so, that's a lot of emulsion being used!

Could you describe your process in detail? What taking some pictures so we can see your exposure setup?

How are you making your transparencies? Ink jet printer, laser, hand drawing your design with a Sharpie?

How far from your screen is your light source?

As many details as you can give, the better we can understand why this is happening.


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