Top Ten Worst Screen Printing Mistakes

And How to Fix Them

1. Art problems -
A. Start with good artwork, properly prepared. Don’t use a low resolution jpeg and think you will get a good screen print out of it. The art should be a minimum of 300 ppi at print size.
B. Make sure you can print the design correctly and match it with the correct screen mesh for the artwork.
C. If you have a customer, make sure they sign an approval of the final design. You’d hate to reprint a design at your own expense because a word was misspelled!

Here's a nice design made to look distressed. (a new design we are testing) Because of the small details we burned this art on 156 mesh screens to print on t-shirts.

2. Screen Exposure problems -
A detailed list of screen problems here: Troubleshooting Screen Problems

3. Bad registration -
A. Screens can become loose in the bracket on the press if not tightened enough.
B. The platen might be moving if the screw is not tightened enough. Turn it as tight as you can being careful not to strip it.
C. The shirt might be moving if you don’t have enough adhesive on the platen.

4. Screen break down -
A. If the screen was under exposed, the emulsion can loosen and come off. We always “post-expose” the screen. Which means we either place it in the sun after it’s been washed out and dried or we expose it again in the exposure unit to set the emulsion.
B. The squeegee can wear through the emulsion on a long print run or on a screen that has been used a lot. If the worn spots are outside of the design area you can clean the screen, spread a thin coat of emulsion over the worn areas and expose it to repair the bare spots.

5. Bad ink curing, ink under cured or over cured -
A. Check the curing temperature with a temperature gun. And know what temperature the ink is supposed to cure at, of course. I usually print out a sheet of instructions that go with the ink and stick it to the lid of the ink container.

My instructions unfolded. They are stuck to the lid with double-sided tape.

6. Incorrect squeegee angle -
A. Try for a consistent 45 degree angle when applying ink to the screen. Ink goes on pretty smooth at this angle. At an angle of 60-degrees or more, the ink may not get through the mesh correctly and evenly. An angle of 30-degrees or less can make the ink print too heavily onto the fabric.
B. You may need to experiment with the squeegee angle and practice to get it right, see what works for you and keep it consistent. You can also experiment with a “push” print stroke as opposed to the usual “pull” print stroke. There are cases when a push stroke can be useful. But always do one or the other, don’t switch between strokes.

Freddy usually screens a bit closer to a 60 degree angle, but that's what seems to work for him.

7. Ink spots or smudges on garment or product -
A. Keep the work area and your hands clean.
B. Check the screen carefully for pinholes and fill them with a screen touch-up pen or cover them with a piece of tape.
C. Wash out small spots with a wet shop towel or a spot cleaning gun. If you can’t clean it, keep the shirt and use it for test prints.

8. Design placed incorrectly -
A. Line up you screen carefully. We usually use a t-square to make sure the design is straight.
B. Not all shirts or other garments are sewn correctly or consistently. So you may not be able to use the collar or center crease to position a shirt. The most reliable way I’ve found to center a shirt is this: How to Center a Shirt for Silk Screening

9. Too much ink is getting printed onto the shirt -
A. You may be using too much pressure. Don’t press down too hard on the squeegee and use even pressure all the way across the print.
B. You may have gotten too much ink into the mesh on the back flood. Be careful as you back flood and don’t press down too hard or go over it too many times. If your ink does get too heavy, pull a few prints on test sheets without back flooding to clear out the screen.
C. The ink may be too thinned out
D. You may have an old squeegee with edges that are rounded and need to be sharpened.

10. Too little ink is getting printed onto the shirt -
A. Use a coarser mesh.
B. Make more than one squeegee pass to print. We sometimes do as many as 3, but that is usually the most we need.
C. The screen may be getting clogged. We will rub the underside of the screen with a wet shop towel and then screen a test print or two to try to clear it out. We print on test print squares or misprinted t-shirts and use blank newsprint when test printing for posters and art prints. (Note: We have been told that spraying water mixed with a little bit of dish soap on the underside of the screen before you put any ink on it helps when you print. We mean to try this next time we print.)
D. Try printing on a soft base. We sometimes use a platen covered in neoprene fabric. Especially when we want to print over collars or seams (more on this topic later).

Here's Freddy adding more ink to a screen. You can see that there wasn't enough ink to back flood properly and it's spotty behind the cake spreader he uses for the ink.

Mistakes will happen, but my best general advice is to work carefully to head off problems before they happen.

Next: How to prepare a screen for printing.

How to Center a Shirt for Silk Screening

Some shirts that you will buy come with a center crease and many people use that center line to line up the shirt. I do too, but being a careful, ok, perhaps paranoid type I don’t trust that crease. I know that the crease can be off center or the shirt can be sewn crooked and it’s best to double check your placement so that you try your best to avoid a misprinted shirt. Also, not all shirts come with that center crease. Most of the recycled and higher quality shirts we buy don’t have one. A lot of the shirts we buy that don't have a center crease have side seams, however.

So, here’s how I line up a shirt on the platen.

I draw a carefully measured center line down the center of the platen. This is always good to have as a visual measure.

We will decide where to place the design on the shirt and figure out where the design on the screen will fall on the platen and I put a piece of masking tape on the platen and draw a mark about where the collar should fall to make the design print correctly on the shirt.

I open up a shirt from the bottom and slide it onto the platen all the way to the shoulder seams, making sure the shoulder seams are even on the platen edge.

I pull the shirt back carefully, keeping it straight until the collar hits the mark.

Then I use my thumbs to measure the distance from the edge of the platen to the arm hole seams and check to make sure they are the same distance on each side.

Then I slide my hands under the platen until my fingers are touching the side seams (if the shirt has side seams) and measure if the distance is even. If my fingers are touching the side seams and the platen is falling at the same place on each hand, the shirt should be pretty centered.

When the shirt has no side seams and no center crease, it’s a little harder. For the smaller sizes I use the same method as above and just look at the arm hole seams to see that the shirt is centered. For the larger sizes I fold the shirt in half lengthways and create a center line that looks right to me.

I pick up the shirt by the center line and get Freddy to help me slide it onto the platen and I place the center that I have pinched onto the center line drawn on the platen.

That’s how I place the shirts. Other people have other methods and you should check out everything you can and decide what works for you. Let me know if you find a better way. I'm always hoping to learn something new!

Next: Top Ten Worst Screen Printing Mistakes

Why Screen Print?

I’m an artist. I’ve always been an artist or intended to be one. I’ve done many different types of art... album art, magazine illustrations, book covers, comic books, trading cards, paintings, logos, product concepts and designs, packaging, brochures, maps, advertising, web sites... and t-shirts and posters.

I drew this! I'm an artist!

One thing about being an artist, unless you are simply exhibiting paintings, you are at the mercy of the people who reproduce your art. I dealt with that problem very early in my career by becoming an expert in printing and separations. That helped a lot.

But the passion to create has always been there. Along with a desire to communicate thoughts and ideas. After having other people print my work on t-shirts and posters, which was expensive and not always what I wanted I made the decision to try it myself. Control freak? Maybe. But I have a vision and I want it to be right. And affordable. So for me, screen printing was the way to go. But...

What if You Don’t Want to Screen Print?

Can you still create and sell your ideas on stuff? Yep. I do that, too. It may seem like an odd topic in a blog on screen printing, but it’s just another way to get your creativity out to the public. And maybe even make some money. You know... if you’re into that.

Let’s talk about on demand merchandise companies. I use Zazzle and Cafe Press, so I’ll cover those two. There are many more like Printfection, Spreadshirt or Pikistore. DeviantArt and Imagekind also specialize in art prints on demand. There’s even The Game Crafter that lets you create a board game and offer it on demand. Clever stuff!

The way these sites work is this... you create a design, upload it to the site, choose the products that the design can be printed on, place it into your own “shop” on their web site and it’s offered for sale. When someone orders a product like a t-shirt or coffee mug, the On Demand Company elves at the On Demand Company factory put your design on a blank product and ship it out to the buyer. And you get a tiny bit of the sale. Not a lot, but it’s not much work on your part and the sales add up. The main advantage it that it’s easy and open to anyone with an idea.

I’ve called Cafe Press and Zazzle my product testing sites. Some of the designs I come up with are too hard for us to print right now or I’m just not really sure if they are any good or maybe they don’t quite fit with what we do or maybe I’ve gone crazy and the design might be no good at all. Actually, I think I may be crazy quite a bit. But you can throw some ideas up on Cafe Press for little or no cost and see if if has potential. It’s also very fast for when you are impatient and caught up in the fire of inspiration and must have an idea out right away. This happens to me a lot.

I don’t know how to silk screen this one yet, but Cafe Press does it just fine:

Create your design and upload a computer file of the image to the site. It doesn’t need to be color separated, it will print onto the products just like an inkjet printer would. Cafe Press has good beginner instructions. The way I’ve chosen to do the images is I do a 300 dpi image at the largest size it would print on a product and save it as a PNG file. I’ve found that quality is very good and reproduces well.
Beginners Image Workshop

Cafe press also has resources for folks who want to sell on their site.
Resources for Shopkeepers

Cafe Press offers selling tools like this widget that can go on a web site. Or blog! It can be made in different sizes and colors to match your page’s scheme.

Make Custom Gifts at CafePress

Zazzle offers a similar panel to imbed in your web site or blog:

Look for a personalized gift at Zazzle.


You can use the same designs to upload on any of these on demand sites, so you can have multiple stores if you want to. I’ve tried these three:
My Cafe Press shop:
http://www.cafepress.com/seriousdesign

My Zazzle Store:
http://www.zazzle.com/JayJayJackson

My Printfection store
http://www.printfection.com/seriousdesign

All three are good, Cafe Press is a little more user friendly, Zazzle is more specific and you can make your products customizable by the person buying. Both Cafe Press and Zazzle seem to get good amounts of traffic, I sell a bit more on Cafe Press, but promoting your shop is up to you.

Some of my new designs!

Even an iPhone 4 case!

Next: How to Center a Shirt for Silk Screening

Drying and Curing Inks DIY Style

We started our operation on a small budget. A really small budget. We bought our no frills 4 color press for around $500 (new, off of ebay), bought some shirts and basic supplies and that was pretty much it. We scrounged and made do with everything else for a while. And we used a heat gun to cure the discharge and water-based inks. We also used the heat gun the couple of times we tried using plastisol inks. It worked, but with a few failures. Here’s what we used to do:

You can only cure a small area at a time with a heat gun, 5 or 6 inches around maybe. The discharge ink needs to be cured 30 - 45 seconds, until it changes color. Before it dries. So it was a problem because the t-shirts get screened faster than you can cure the shirts. We dealt with that problem by doing small runs of shirts. A normal run for us was 20-30 shirts. It was less of a problem on smaller designs, a big problem on large ones.

No Problem

Problem

Our heat gun curing station was pretty funny. We used a foil steamtable warming tray turned upside down on its wire frame. Hey, it worked and it was free. We never caught one single thing on fire. Singed a shirt once, but everyone does that.

We tried doing plastisol on some shirts and tried all the tricks the videos said to tell if the ink was cured. The plastisol ink is supposed to cure for 45 seconds at 320-350 degrees. I would measure the temperature to get my distance right, controlling the heat on the shirt by the distance of the gun from the shirt (about 4 or 5 inches away to get 340-ish degrees) and count to 45 while curing a little area. Crazy, huh? Most of the shirts were ok, but we had a couple of them where the design was damaged when washed. I supposed it hadn’t been cured enough. And some we overcooked and the design got weird looking and too shiny in spots. So the heat gun is tricky with plastisol ink, in our experience. Larger designs are really hard. With the discharge ink, at least you can tell when it’s cured... it turns a lighter color as it discharges the color from the shirt.

We really needed to get a forced-air flash dryer to take our business to the next level, but that was a distant dream since they are quite expensive. I wrote about it on the Deaths Head blog back in 2009.

We kept saving up, even as we went through some tough economic times, and I kept searching for any reasonable solution. I called manufacturers and spoke to sales reps about flash dryers to learn as much as I could about the equipment out there. You can read a lot, but sometimes you have questions that only an expert can answer.

So I finally found a less expensive forced air flash unit, the Ranar DA-1616 that seemed like it would work for us. It had what we needed for discharge inks:
- Forced air
- 16 x 16 inch coverage (we do larger prints, but we can move them around)
- Infrared heat source (a better option than heat coils)
- A 110 volt plug! (the only one I could find at the time that had this)

The thing that worried me was that no matter how hard I searched on the web, I couldn’t find any first hand information about the unit. I asked on forums like gigposters.com and t-shirtforums.com but no one knew anything about the Ranar dryer. Which worried me a little. One of our suppliers, Pocono Screen Supply sold these dryers, so I called them for information. They really didn’t tell me much more than what it said on the web sites I had found, but I decided that because of the price difference this was the unit we would get. Sold here.

The day finally came when we had enough money to order the unit! Waiting for it to come was agony! We ordered it right before Christmas 2009 and the company was closed for the holidays and didn’t ship it until almost the middle of January. So when it came, we were jumping around for joy! We hauled it to the studio and unpacked it and gazed in wonder at the mysterious looking plug. What was this?

We had never seen this kind of plug. My first thought was that they had sent us the wrong unit and it was a 220 volt instead. I called the company and they checked with Ranar and, no, it was the right unit, a 110 volt. But it was a 20 AMP unit. Most circuit breakers are 15 AMP. The circuit breakers in our studio were 15 AMP as it happened. Heck, we replaced the wall socket with the correct socket for that plug and tried it anyway. We wanted that flash dryer baaad. It blew the fuse. Again and again. There was no way. We looked into changing the fuse to a 20 AMP. There was no master cut off switch on that fuse box. We couldn’t find out where to shut off the main power to the studio. So the power couldn’t be cut off to the fuses and I wasn’t going to let Freddy try to hot swap a fuse in a live box. Damn. So what were we to do?

What else could we do? We looked for a new studio.

For a long time we had talked about finding a live/work space. We had started out in the shared basement of Freddy’s apartment building, but the landlord told us he didn’t want us screen printing down there. We did it secretly for a while, anyway. But hiding everything all the time was a huge pain. We tried screen printing inside Freddy’s tiny apartment. We even tried my apartment in Brooklyn. None of these were solutions. One day our wonderful friends from the band The Saints of Pain generously offered to share their rehearsal space with us and we set up our beautiful new studio in the rooms in the back of the space they rented. But there were water and power problems with the building. So, I gave up my apartment of 26 years in the beautiful, historic Park Slope neighborhood of Brooklyn (sigh) and moved in with Freddy to save money. We needed to find a new place to work. And live. We really needed that to be the same place. It took about 5 months of hard looking last year to find a place that we could afford that had enough space. I blurted out “We’ll take it!” once we examined the fuse box in the basement. It had some 20 AMP fuses in the basement! Oh yeah!

And the first time we used that flash dryer to cure shirts was sweet! Very, very sweet. It smelled like victory. Stinky, stinky victory. We’ve been using it for a few months here in our new place.

So, here’s the low down on that Ranar DA-1616 flash dryer for anyone who finds this on the internet, like I couldn’t.
- It’s a 110 volt unit and runs on regular household current, but it takes 20 AMP fuses and wiring and a special wall socket. We were unable to find an extension cord or adapter.
- It takes about 8 to 10 minutes to warm up fully.
- We were told by the manufacturer that it should be run on the highest setting at all times and to adjust the temperature by adjusting the distance of the unit from the shirt. That has worked fine for us, by the way. You can adjust the top up or down and it swings freely around. It has a handle on top that stays cool.
- We were advised that the unit works best if the surface under it is metal. We placed an old empty filing cabinet under it and lay the shirts, etc. on that. That has worked fine, too.
- I monitor the temperature closely with a laser sighted temperature gun until I feel the results I'm getting are consistent and then I only check occasionally through the run.
- It has worked well and even cured some plastisol shirts we had to do to replace some of the damaged ones.

Some of the fruits of our labors are here:
Deaths Head Designs Shirts

Next: Why Screen Print?

Finally, a good opaque water-based white ink!

We had tried a few water-based white inks and they weren’t as opaque as we would want for most things, ok really for anything, so for a while now we have used white discharge ink whenever we wanted a good white on a black or dark shirt. Which works great and we love it. It does have a couple of drawbacks... we found a couple of brands of shirts and a few colors that don’t discharge well. And when you screen on a cotton/poly blend only the cotton discharges. it’s mostly not a problem, but we were very happy to find a truly opaque white ink for those cases when white discharge won’t do. And it has been very easy to use.

Ryonet’s new OP White EnviroLine Water Based Ink (By Matsui)

We’ve used it for a few projects now, so I feel pretty good recommending it. Here is Freddy screening a shirt with it. We used it right out of the container without adding anything at all to it. You can tell from the photo that it’s pretty sticky, but it doesn’t dry up too fast so you can screen at a comfortable pace.

We used this ink on cotton canvas tote bags and messenger bags that don’t discharge well. We also screened some cotton t-shirts that we wanted to look like construction company shirts. Here are some closeups of the results.

Here are the instructions for the ink:
PRINTING: For best performance heat the pallets to 140 degrees F. before printing. Heating your pallets will help retain the ink on the garment and allow for wet on wet printing without flashing in between. For light color fabric use Matsui ECO-Series RC through a high mesh screen. For dark colored fabric the use of 301 Transparent White as an under-base. For a softer hand use Matsui’s DSPS Discharge (see under basing below). Screens should be flooded if printing is stopped for any period of time. When loading water base ink into your screens, use a good amount of ink in order to insure the ink doesn't dry in your screen. Print with a pull stroke for best results. Back flood screen with a lot of ink gently so ink is not pressed through the design. You shouldn't be able to see your screen or image through your back flood.
DRYING/CURING: The 301 Enviro-Series ink must be cured for 2.5 to 3 minutes at 300 to 320 degrees F under typical infrared heat.
Curing Options: Water based inks cure differently from standard plastisol inks. While plastisol inks cure with infrared once reaching 320 degrees, water based inks cure best with air movement and heat. Air movement is preferred to drive water out of the ink and blow away steam so heat can cure water base pigment properly. Without hot air movement across the ink, water based inks will take much longer to cure. In good air flow, water based inks can cure in under 1 minute while it may take 2.5 to 3 minutes in a standard infrared dryer. (Paper can be allowed to air dry)

Here's what we did: We didn't heat the pallet before printing since right now the flash dryer is in the other room. We just screened the stuff the way we do everything else, following the guidelines as far as using a good bit of ink and putting down a good thick back flood, and laid the things out to dry. We found that the ink air-dries somewhat slowly. We let the ink dry about an hour (it was still tacky in a few spots) and then we cured it under our forced air flash dryer. I let the screened item get up to around 340 degrees and measured the temperature with a thermometer gun (Raytek MT4 Mini Temp) and let it cure at that temperature for 40 seconds or so. The total time under the flash dryer was probably a minute and a half to two minutes. You could cure this with a heat gun, too. We are very pleased with the results overall.

The bags and t-shirts are for sale on our web site!
Cabeza de Muerte tote bags
Cabeza de Muerte messenger bags
Zombie Proof shirts

Next: Drying and Curing Inks DIY Style

Birth of an Award-Winning Poster

A bit of my creative process.

Got the job one day to do a new poster for Leviathan, the number one band I did posters for. They were opening for Six Feet Under, death metal band extraordinaire. I had been doing some sexy pin up girls on the posters for that band, so I thought I would do another one. The name of the band, Six Feet Under, does suggest a death-oriented theme so a sexy, deadly pin up girl was one idea I had. I love horror movies and every once in a while the girl ISN’T the victim. lol. So I settled on the idea for a girl with a bloody axe who may have just gotten some guy ready to be put six feet under. It turned out to be one of my most successful posters.

I had pitched the idea to the band and gotten a go ahead on it. I played around with some loose sketches and looked at my girl photo reference files to see if I could find a good pose. I like to collect old photos from the 40’s and 50’s. Mostly I like the coy, flirtatious body language and the weight of the women more than the modern look. I find that the women in most modern photos are too thin to look sexy to me, I'm repulsed by breast augmentation surgery and the body language is totally different. A sort of forced, self conscious sexuality that lacks that sense of fun many of the older pin ups have. I also like the quality of the light in the older photos. So I found a photo that had a nice pose and attitude to base my drawing on. I generally don’t stick too close to the photo reference, but use it as a guide to help me make the pose and proportion believable.

I got my boyfriend to take photos of my own hands holding a hammer behind my back to help get the hands right. Hands are difficult for me so I really have to work at them. But I can’t show that photo because I’m not uploading a photo of MY bare butt. lol. The drawing worked out pretty well and I inked it. I actually did the blood on the ground separately on another sheet of paper because I didn’t plan ahead and ran out of space on the first sheet. Since getting used to working with the computer, I sometimes work kind of rushed and sloppy and just fix things later. I figure the end product is what matters. I don’t like to sell my original artwork so I don’t go into a job with the idea of producing the art for a secondary sales market. Many people do, and that’s just fine. I guess I just can't wait to see the final result so I'm always in a rush to get to that point. Besides, technique isn't what matters on posters like this as much as it would on a painting. So, I scanned everything and put it all together in Photoshop and cleaned up the line work.

I knew I wanted two of the colors to be black and red, but it took a little experimentation to decide on the aqua blue. Once I tried that I liked it immediately. The icy coolness seemed good for a beautiful axe murderer. And the aqua has a nice vibration against the red, since it's close to the compliment on the color wheel.

One thing I try to infuse into all of the pin up girls I draw is a sense of the woman being in control, and having fun. My girls are not victims, even when they are chained. They are avid participants in, what I hope is, sex-positive imagery. I find the popular fad for sad, sexualized child-women in gothic and outsider art very unpleasant and I consciously avoid any hint of that in my own work.

Once the poster was done and I got final approval from the band I arranged to have it screen printed. Luckily the band was willing to come up with the money to have Diesel Fuel do the job. They are very good. I did the separations and supplied some pantone colors for them to shoot for when mixing the inks and sent the artwork off over the internet. No more Fed Exing or mailing artwork... I love it. Things are so much easier now. An artist who remembers how things used to be can’t help but marvel at it.

I am a member of the gigposters.com web site for poster artists and fans and I upload all of my posters to the site. And the Six Feet Under poster won the Poster of the Week award! Which is very exciting. It also helped with sales and got loads of attention which led to doing more posters. So that was very nice! If you are interested in owning one of the Six Feet Under posters, we still have a few left, here on the Deaths Head Designs page.

Next: Finally, a good opaque water-based white ink!

10 Things Never to do While Screen Printing Water-based inks and Discharge inks

Don’t stop, slow down or take a phone call or Twitter break. Keep printing. If the ink dries in the screen it’s trouble. If you do have to stop you can try wrapping the screen with plastic wrap. We've tried that with mixed results. And by mixed, I mean not really successful, but others have reported better results.

Don’t put too much ink on the screen. It will start to dry up and become gloppy, to use the technical term. If you put too much ink on the screen at once it may become thick and uneven and be hard to get through the screen mesh.

Don’t put too little ink on the screen. Be sure there’s enough for a good back flood stroke to protect the ink from drying in the image you’re printing.

Don’t leave your ink container open. Keep it covered as much as you can so the ink doesn’t get gloppy or dry up on the edges.

Don’t print too many different colors unless you are pretty experienced at it. The more colors you are printing, the more time the ink has to dry up in the screens. But it depends on the ink. Some inks dry more slowly. We do 3 colors pretty well with Aerotex inks. 4 not as well. We’re getting better.

Don’t zone out. Go carefully, keep checking your work and making sure no problems are cropping up and you can avoid expensive mistakes. In screen printing, mistakes generally cost.

Don’t guess at curing temperatures. Buy an infrared thermometer gun. We try for around 325 or 350 degrees for discharge inks and also for water based.

Don’t rely on your memory. Make notes. Write down exposure times, inks used, mesh counts, what worked right, ideas, inventory, everything.

Don’t wait to wash out your screen after you finished printing. Get some water onto that thing right away. And if you start having drying problems during a run, mist the screen (on the ink side) with a light mist of water.

Don’t think you can get away without test printing. Always test print if you are doing something for the first time, or haven’t tried something in a while.


But, DO have a good time making cool stuff and especially enjoy wearing your beautiful and very comfortable eco-friendly creations!

Model Tony Robinson, actor and artist, enjoying the shirt we made especially for him. Check out his work here.
The Liberal, Born to Raise Issues shirt is available here.

Next: Birth of an Award-Winning Poster

Why Screen Green?

Trying to get people to stop using toxic chemicals is like trying to convince someone to quit smoking. Until they encounter a problem with it, the problem just isn’t real to them. And just like smoking, it can take a long time for toxic chemicals to affect a person’s health to a noticeable degree. Unfortunately once it has affected your health, it’s usually too late. At that point you have to do damage control.

Pollutants and chemicals in the home and in our immediate environment are turning out to be more dangerous to our health than was ever realized. And what has that got to do with screen printing?

To quote Ronald Fuchs and Michael McCann, Ph.D., C.I.H.

“Silk screen printing is one of the most hazardous processes in the arts and crafts. Dermatitis, narcosis (dizziness, light-headedness, fatigue, nausea, lack of coordination and headaches), eye irritation, adverse reproductive hazards including increased risk of miscarriage, and serious neurological problems can all result from the processes of screen printing. Traditionally, silk screen printing has been performed using organic solvent-based materials. Water-based inks containing less hazardous ingredients provide a safer and increasingly popular alternative.”

Read the full article here:
http://www.uic.edu/sph/glakes/harts1/HARTS_library/silkscrn.txt

We didn't want to use plastisol inks because I just didn’t like them. I find the heavy plastic on a shirt uncomfortable and unappealing. But it turns out there’s more to be concerned about. A major health concern about plastisol inks is not only that they are PVC-based but that they contain phthalates. There’s been a lot in the news in recent years about phthalates and quite a bit of research into possible problems. Medical research has linked high doses of phthalates to damage to the liver, kidneys, lungs and testes in rats. Another medical study suggest that phthalates contributes to allergies in children. Many people, like me, choose not to wear plastisol screened clothing which comes into close, extended contact with your porous skin.

What many screen printers don’t realize is that there are better alternatives to doing things the old-fashioned toxic way.

Ways to do Greener screen printing

- Use an inkjet printer for your transparencies. Inkjet printers are greener than film output and are cheaper.

- Use water-based or discharge inks. Check into what is in them. You could even look into the new phthalate-free plastisol inks if plasitisol is what you want to use.

- Know what you are buying. Do the research. Have Material Safety Data Sheets for all of the products you buy and read them. Then use good judgement about what products you use.

- Use water-based screen printing adhesives, like Pro Bond or Tex Tac instead of solvent-based aerosols like Mist. These cost less, a LOT less as it turns out, and work better also. I switched while doing research into how to make our business greener.

- Use eco-friendly cleaners. The ones we use work better than their toxic counterparts.

- Buy shirts with recycled content or at least organic cotton. We are loving Anvil's new recycled cotton blend shirts we've been testing out.

- Put a simple filter, even one just made with a pieces of screen or cloth on the drain of your washout booth or slop sink. This will help stuff like emulsion from clogging your drains as well as protecting the water system.

- Think about ways to recycle and also ways to reuse old stuff. I wrote up a bit of what we have done here on the Deaths Head blog.

- Be careful, plan ahead and make fewer mistakes. Fewer mistakes reduces waste and saves you money. It can be done.

Extra Reading:
Here’s a very good article on the subject by the author of one of the best books out there on the subject, Water-Based Screen Printing Today
http://www.nontoxicprint.com/screenprintingbasics.htm

Next: 10 Things Never to do While Screen Printing Water-based inks and Discharge inks

Troubleshooting Screen Problems

This is a run down of common problems with coating, burning, washing out and reclaiming silk screens for printing.

Problem 1. The emulsion does not go onto the screen smoothly and evenly.

A. The mesh may have loosened up and have uneven tension. This is especially a problem with wood frame screens once they start to get old.
B. Your emulsion may be old or have dried bits that have fallen into it. Keep the emulsion container clean and try to refrigerate it if you are not going to use it up pretty quickly. Check the shelf life of the emulsion you are using.
C. Have you remembered to remove the rubber edge protector on your scoop coater? Don't laugh! You’d be surprised how many people make this mistake.


Problem 2. Emulsion is washing out all over the screen.

A. The screen was not exposed for a long enough time. You may have to experiment to get the right exposure time for your equipment and screen.
B. The emulsion was applied too thickly on the screen and not exposed long enough to overcome the thickness.
C. The emulsion may have been applied unevenly. The thicker patches may wash out and the thinner areas may be ok. If the emulsion is applied unevenly the thicker areas take longer to expose than the thinner areas, so you won’t get a good exposure on the screen.
D. The lights in your exposure unit may be getting old and losing their potency.
E. The emulsion was not cured. Make sure you allow enough time for the emulsion to dry completely and cure in the screen.
F. Too much water pressure can cause the emulsion to wash out and you should only use cold or lukewarm water.


Problem 3. It’s hard to wash out the image on a screen you just burned.

A. The emulsion on the screen could be old. When a screen has been coated and sits around too long, the emulsion gets harder to wash out.
B. The screen may have been exposed to some UV light. If there’s been too much light exposure to the screen the image area could be partially exposed and hard to wash out or may wash out unevenly.
C. Your image on the transparency may not be solid black. If the transparency lets light through the image area can become slightly exposed. It’s possible to double your transparencies, just be sure to line both copies up carefully.


Problem 4. Losing fine detail when you burn screens.

A. The transparency may not be making good contact with the screen. Make sure you place the transparency with the print side next to the screen and weight it well enough to make good contact. A vacuum exposure unit is best, but if you don’t have one of these you have to be more careful.
B. The screen is over-exposed. If the exposure is too long, the fine detail will not wash out and will be lost.
C. The light you are using to expose the screen is not angled correctly. The light source needs to be as straight on as possible, in other words, 90 degrees to the screen.
D. The light source may be too weak. If you are using a weak light source and a long exposure there is more risk of ambient light or light scattering contaminating the exposure.


Problem 5. Pinholes in the screen.

A. The glass over the lights may be dirty or have dust on it. Same with the transparency. Be sure to clean the glass before you burn a screen and the transparency before you tape it onto the screen.
B. Dust or dirt could have blown onto the screen while the emulsion was wet.
C. The emulsion may not have been completely cured.
D. If you do get pinholes and they aren’t too big, you can either cover them with tape or you can use a screen touchup pen or fill them in with a little more emulsion and let it dry and expose it to UV light to harden it.


Problem 6. The emulsion breaks down while you are screen printing.

A. The emulsion may not have been exposed long enough. We expose the finished screens to UV light after they are burned and washed out and have dried. Either with sun light or placing the screen back onto the light unit.
B. The emulsion is applied too thinly on the screen. The emulsion should be thin and even, but coated at least once on each side with a good scoop coater.
C. The emulsion may not have been properly cured. We usually allow a minimum of 24 hours for a screen to dry.
D. Wrong type of ink for the emulsion you are using. We use dual cure emulsion that works with both water-based and plastisol inks, but choose your emulsion carefully and check to make sure it works with the ink you intend to use.
E. Too much squeegee pressure or screening too many prints can cause the squeegee to wear down the emulsion. Be sure to use the correct emulsion for the type of ink you are working with and coat the screen an extra time on the inside of the screen where the squeegee will make contact if you will be screening a large number of impressions.


Problem 7. The screen is hard to reclaim.

A. The emulsion on the screen may be old. The longer the emulsion sits on your screen, the harder it is to reclaim.
B. The reclaiming solution dried in the screen. Once the reclaiming solution dries on the screen, it becomes permanent and ruins the screen. Always be careful to wet the screen before you apply the reclaimer, keep it wet and work the reclaimer around on the screen with a brush or scrubbie.
C. The emulsion may be uneven. If the emulsion is thick in spots, like around the edges, it may be hard to get all of the emulsion out. Though if it’s only on the edges, it may not matter.
D. You may not be using enough water pressure. Try using a pressure washer, a special hose like the one Victory Factory sells or even try a coin-op DIY car wash.
E. Ink may have dried in the screen. If the ink was not washed out thoroughly it may have dried in and blocked parts of the mesh. You can try a haze remover like Enviro Haze. But if the ink has really dried in there, the screen may be ruined.


Here is a handy chart from Speedball that I found. It may help with estimating exposure times if you are using light bulbs.

Next: Why Screen Green?

Rocking the Basics Part 2 - Water Based and Discharge Inks

Just Watch the Videos! How Easy is that?

There are many videos and tutorials out there about the basics of silk screen printing. You can check youtube.com, vimeo.com. Instructables.com, wikihow.com and ehow.com are all places you can find some information on the basics or on different techniques for screen printing or decorating clothing.

Here are a few water based and Discharge inks videos excerpted from the Ryonet DVD. I recommend the DVD. It has helped us learn.


Mixing Discharge ink (Note: They say the ink is good for 8 hours but we notice a drop off in print quality after 4 or 5 hours)


Discharging the Discharge ink on shirts.


Clearing dried water based ink (We use the RC water-based inks, they are very good, but the ink will dry in the screen sometimes)


Enviro Wash Screen Cleaner (We use this and it’s great)


I really couldn’t find anything good on using Discharge Paste, which we use quite a lot. I think we will have to make one. If you would like to look over my blog post on Discharge Past here it is.


Extra stuff:

Recession advice for screen printers (Don’t have a job? Make your own!)


Got a Yudu? Here’s a nice tip:
Coat Your Yudu Screens With Liquid Emulsion

diyteeshirts.com YUDU Hacks: Coat a Yudu Screen from DIY Teeshirts on Vimeo.

Next: Troubleshooting Screen Problems

Rocking the Basics Part 1 - Coating and Exposing the screens

Just Watch the Videos! How Easy is that?

I haven’t covered the basics of screen printing because so many other people already have. There’s a ton of information out there that has helped us so I’m just going to link a bunch of it here! Sit down with some popcorn and watch!

Ryonet has many good videos on youtube and they sell excellent DVDs. Catspit Productions has some great videos. The only drawback (for us) is that Catspit only prints with toxic Plastisol ink. We don’t use that ink very much, only on one type of shirt, our UV reactive shirt, prefering to stick to more evironmentally friendly products. But they are a great source of DIY information. Basically, you can find most any type of beginner information on youtube.com. You can find a master list of the stuff we use here.

Prepping And Coating Screens
We don’t degrease or abraid the mesh. I know you’re supposed to, and we did at first, but then we found we didn’t need to after all. You have to find what works for you.


Putting emulsion on your screen
We mostly use one coat on each side. We also work in normal room light, fluorescent or 60 watt incandescent, but we are using dual cure emulsion. We just put our screens in a big cardboard box with a black cloth draped over it to dry and we separate them with votive candles or small jars in between the screens. But the storage closet is nice!


Another - How to Put Emulsion on Your Screen (Nice one!)


Placing Your Film On The Screen


Image Placement on the Screen and Screen Exposure
Click to Watch

How to Burn a Screen
Good information and a cute girl! We basically do things much this way but we use dual cure emulsion, expose the screen for 5 minutes and do all of this in low normal room light, but no sun light.


A couple of different ways to expose your screens


Screen Exposure Problems PART 1


Getting Your Art To Screen


Washing Out The Stencil & Reclaiming
We dab our screens dry with a paper towel and sometimes dry it further with a hair dryer, NOT held too close because nylon mesh can melt. We also use a special hose from Victory Factory instead of a pressure washer. A pressure washer is better, but you can get along with less.


 Here is a Speedball exposure chart that may help when exposing screens using light bulbs.

Next: Rocking the Basics Part 2 - Water Based and Discharge Inks

The World’s Most Painful Poster

I know I keep mentioning this poster. Our first. Oh, the horror. The first time we tried to screen print a poster it was a whirlwind of trouble. One weekend of pure hell. If this project didn’t make us give up, nothing will. But I will explain all of the problems that we had and maybe that will help if you run into problems.

Before Freddy and I started screen printing, I had designed some posters and had them printed by several different screen printers, all of whom did a wonderful job. But it was time to do our own. We started small. Our first poster was 12” x 18” and 2 colors.

It started out just fine. I took some photos of Freddy posing with a skull I had laying around the house and did the sketch, inked it and did the separations, planning on a simple 2 color poster in classic red and black. Freddy got the poster press built and ready in time for the weekend printing session. We had the screens made for us at Standard Screen in Manhattan since we weren’t experienced at burning screens yet.

The posters I had drawn before were silk screened by other people and I had always done the separations myself. I was very sure to make the posters pretty easy to screen and give the screen printers good separations. But on this one, I got lost in the creative process and created a bit of a difficult registration issue. I did something that is generally not a good idea and had 2 colors need to line up precisely to look right. Below is an example of what I mean. The top picture is the black screen out of register and the bottom picture shows it correctly in register.

The press Freddy built is capable of very accurate registration... when it is working right. Anyway, I had done all of the research on printing posters so we began, thinking we knew what we were doing. We hung the paper up in the basement overnight to let it acclimate so that it wouldn’t change shape on us as it absorbed the humidity or changed temperature.

We started on our adventure. We ran into trouble almost right away. We could not get a good print out of the red screen. Below are some examples of the problems we had.

Here the ink squeezed out under the screen. And perhaps you can see that the texture of the ink is blotchy, not smooth like it should be. The ink we were using was too thick and needed to be thinned, but we did not know. We used the Speedball acrylic ink right out of the jar. Freddy had to press so hard to get it through the screen that it bled under the masked areas. And it was so sticky that it stuck the screen down to the paper and didn’t pop back up like it should even though we increased the off-contact (or space between the screen and the paper). Now we know that it may have been possible that the ink was spreading out under the stencil like that BECAUSE we increased the off-contact. Sigh.

We also had problems with the ink not going on evenly and skipping some areas. Usually the same areas. We would later discover that we had a bad squeegee.

Here’s an action shot at our low point with the bad squeegee, bad ink and bad hinge clamps.

We tried to clean the screen out on the press after it would squeeze out like that, but it didn’t work. We would have to take the screen off and go wash it up and wait for it to dry. During one of these breaks, we re-watched a Speedball DVD we had and realized that perhaps the ink was too thick. So we thinned the ink to the consistency we had seen on the DVD and tried again. It was still hard and we ruined a lot of paper, but we finally got 60 good prints. It seemed like it took forever.

Once the red prints dried, we started trying to print the black screen. It was going worse than ever and now we were ruining some of the red prints we had screened. About that time, while we were cleaning up the screen for another try, Freddy noticed that the squeegee wasn’t straight. It had a slight curve on one end. That was one problem. He also felt like the black ink was too thinned out. So we found another squeegee and I mixed another batch of ink, thicker this time and we started again.

Everything was going wonderfully... until we noticed the black was going out of register. It wasn’t lining up and it was different on every print! We found the problem – the hinge clamps weren’t holding the screen tightly and it was slipping around. No matter how we tightened them with pliers and even vice grips, they would still loosen up.

So we took the Staten Island train to the Staten Island Ferry to (oh god why did I move to Staten island? Oh yeah, a house & basement.) Manhattan and then took the subway to the art supply store to buy the good hinge clamps that we should have bought in the first place. Sigh. But we hadn’t known. Buy Jiffy Clamps. Trust me on this. Here’s a picture. The Jiffy clamps and a discarded old, bad clamp.

We mounted the new Jiffy Clamps and screened the rest of the black. At that point we were amazed at how easy it was. We finished screening the posters and they came out beautifully. We even managed to print my tricky registration with very little trouble at that point.

We finished up and hung the prints to dry. We celebrated our victory by watching a silly horror movie... somehow fitting.

Rawk!