# Capillary Film Questions



## shortbuskid (Apr 16, 2011)

I hope I'm not beating a dead horse here. I had made a few shirts last year using a 220 mesh screen and a stencil I cut from some vinyl. My mom, not wanting to see me work harder than necessary, bought me some capillary sheets a while back. I've finally decided to give them a shot and had a few questions.

(these are very rudimentary, so don't over think them)

During the application, if the screen and capillary film doesn't totally dry will it be tacky and kind of run a bit during the wash out after exposure?

And concerning exposure, I don't have an exposure unit, halogen light or, well much anything. I followed the steps I have read on here about exposing in direct sunlight. I was careful to lay down a black cloth, then set the positive on it, placed glass on that to hold it all down and tossed a penny in the corner so I could check exposure.

I read on here it could take anywhere from 30 seconds to 40 minutes. I went out and checked it at 8 or so minutes and looked under the penny. I saw that the emulsion had changed color, what was beneath the penny was the same color as when it started and the rest of the screen was much darker.

Not sure how much time it should expose, I gave it a few more minutes and then went to wash it out. As I previously mentioned, the exposed emulsion got tacky when the water hit it, and the unexposed emulsion didn't wash out. Well, it sorta started to but I had to hit it with some high pressure and moderate scrubbing (the scrubbing also started to remove the exposed portion of the emulsion as well).

So, long winded as it was, what am I looking at here? My instincts tell me the emulsion had not dried completely. But as for the exposure, I'm at a loss. I don't have anything to use to expose it short of a gloriously sunny spring afternoon.

If you read this far, hanks for your attention and I look forward to your feedback.

Mike


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## chuckh (Mar 22, 2008)

OK Mike, here goes....I'm guessing that you don't have a lot of film, but you have to do a test to get an idea for time. Make two screens, one with the size film you need and one with a smaller piece. Once you apply the film to your screens, let them dry horizontally with the print side up. When you peel the backing from the dry emulsion, it should peel easily with almost no sound. If it pulls hard, or make a sticking sound, it is not dry. You can place a fan in front of the screens to assist in drying.

Use a piece of plywood, 1/2" to 3/4" thick and a couple inches wider and longer than your screen. Place a piece of foam that is slightly less than the same dimensions of the inside of your screen, and an inch or two thicker than the screen, on the plywood. Drape a thin black cloth over the foam. Using the screen with the smaller piece of film, and using the positive that you will use for the actual production screen, tape the positive to the emulsion. Place a piece of 1/4" plate glass that is also wider and longer than your screen on top of the positive. Use something to weigh down the four corners of your glass so that the pressure causes the foam to collapse and the screen touches or almost touches the plywood.

Place this in the sun, around noon time when the sun is at its highest point and the rays are strongest. It takes less than a minute in the Arizona sun, and a little longer in Maine. Start with one minute and then wash out and see what happens. It'd be great if you had a couple of screens to use as a test.

Very primitive, but it works. I did it a couple of decades ago, well before I ever purchased my vacuum frame and metal halide exposure unit. Have fun!!


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## shortbuskid (Apr 16, 2011)

Thanks for the quick reply. I was afraid I had over exposed an under dry screen and it sounds like I was right. Sadly I do only have the one screen, but I could cut my cap sheets down I guess so as not to blow through them. That should let me do a test to figure it out. We have another pretty day so I hope I will be around the house when the sun is peaked.

Thanks again,
Mike


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## TYGERON (Apr 26, 2009)

Nix the capillary film.

Don't ask, just do it.

Trust me.


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## chuckh (Mar 22, 2008)

One of the great things about this forum, and there are some really great and not so great aspects, is that you will hopefully get not only opinions, but facts as well. Some people like chocolate and others prefer vanilla. They're both good flavors of ice cream. That's my opinion. 

If I am new and starting out, the ability to make a quality screen with capillary film puts me ahead of the game as I try to learn and understand all the other skills and nuances of screen printing. Consistent emulsion thickness, short screen readiness time, long shelf life, short learning curve...these are just a few of the benefits that I have received over the course of thirty years of screen printing using capillary film.


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## shortbuskid (Apr 16, 2011)

TY, right now I am just using what I have handy. If I nix the film, I don't have anything handy. it's a bright sunny day here in Arkansas so I plan on giving it about a minute outside. Is there any tell tale sign that it was enough time, other than the washout?


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## shortbuskid (Apr 16, 2011)

Ok, just returned from exposing it at about a minute (maybe a touch longer, didn't have any watch with me). The screen washed out,l just took a little more effort than I think it should have. May have still exposed it too long. But the important part is:I figured out what I did wrong on screen/film #1 and now I have a printable screen. Thanks for the tip, hope these shirts look alright.

p.s. the whole reason I am here is because some guy I work with saw the shirt I made last year and threw me under the bus to another guy regarding softball t shirts...somehow I got thrown onto the team as well


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## chuckh (Mar 22, 2008)

As long as you can hit, they won't care how the shirts turn out!! LOL


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## shortbuskid (Apr 16, 2011)

Which is exactly why I'm trying to get the shirts to look good.


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## TYGERON (Apr 26, 2009)

shortbuskid said:


> TY, right now I am just using what I have handy. If I nix the film, I don't have anything handy. it's a bright sunny day here in Arkansas so I plan on giving it about a minute outside. Is there any tell tale sign that it was enough time, other than the washout?


Mike,

I kinda gathered as much. And I could've been more helpful .

I was just kidding about the capillary film. Kinda...

I've *jokingly *declared a moratorium against using it but my bottom line is use what you have to do what you need to do. There are folk who have had great success from their very first screen, continue to do so and wouldn't use anything else. There's the abject opposite and in between. And there are some applications that absolutely require the attributes of film.

Know that all emulsions have a shelf life and you can do a step wedge test to dial in the time. The more accurate method is to use a single step exposure calculator. And you only have to use a small strip of film for step or a small piece the size of the calculator instead of a whole sheet.

And I'm a huge fan of sunlight when available! Here's a link to a good read I've posted before. Note Doug Gibson's story.

Andy MacDougall on Exposure

When the shirts turn out great and folk find out you print, you WILL get more business so read up and get ready (but work on that swing in case they suck rocks...LOL).


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## xysticus2012 (Jun 12, 2012)

have a new Printa machine ....just bought this march...having a heckof a time with my capillary film.....over under exposed not dry enough not sure what i am doing wrong....exposed for the 2 minutes like the package said...film does not want to dissolve at all ...in training it rinsed with in a few moments ..the film then gets a blister like area where the image is and if I continue rinsing the entire film begins to peel like a fruit roll up ...thank goodness for reclaiming screens but I am running out of capillary film and have not had one good exposure ,....some one please help


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## TYGERON (Apr 26, 2009)

Melissa,

There are some very critical steps you HAVE to follow to get good results regardless of what stencil system you use. Your screen has to be thoroughly clean and degreased even if it's brand new. Folk use other stuff but washes and dereasers specifically for screen printing are recommended. There really is no reason the abrade or roughen the mesh contrary to what some may say and it may actually be detrimental. When applying capillary film the screen has to be wet and there can be no air bubbles or dry spots. Some stand the screen and roll the film downward, some upward. Some folk apply it with the screen lying down print side up. Some lay the film down emulsion side up and lay the screen down on top.

Here's one of many Youtube videos:

[media]http://www.youtube.com/watch?v=oELkgn7zUPk[/media]

As far as exposure, the 2 minutes was just a suggestion because there are too many variables that affect the time. You can purchase a single step exposure calculator to figure out your times.


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