Alright, today we’re going to cover how I coat screens with emulsion and dry them safely. First off, you’ll need your screen, some emulsion (I use Ulano QTX), and a method to get the emulsion on the screen evenly. If there’s one piece of screenprinting equipment that I cannot recommend enough, it’s a scoopcoater (That’s the metal trough thing in the photo, in case you don’t know).

I started out putting a bead of emulsion on my screen and spreading it with a squeegee. That method does work if it’s your only option. I did that for about 6 months, until I got a scoopcoater and everything became so much easier and far, far less messy.

 

Fill your scoopcoater about half full of emulsion. If you overfill it, spills happen, like this. I didn’t get any pictures while actually coating screens because I needed both of my hands, sorry. Using the sharper edge of the scoopcoater, I pull one coat of emulsion on both sides of the screen. Coat the back side of the screen first, and then the squeegee side. This will give you the smoothest surface when you actually get to printing. I dry my screens (squeegee side up) in a large cardboard box that I normally store under my printing table. Conveniently, the boxes that my new screens get shipped to me in happen to be perfectly screen-sized.

When you’re done coating, don’t forget to take a plastic card or small squeegee and scrape the leftover emulsion from you scoopcoater back into your tub of emulsion, it’s still good.

 

To make the drying process much faster, I have a flap cut in one side of the box, just large enough in which to stick a small desk fan. I can stack five or six screens in one box, each one separated by pieces of scrap wood, as you can see in the photo. This gives you enough room for the fan’s breeze to fully circulate around your screens.

 

Once the emulsion starts to dry, it becomes light sensitive, so I have a large piece of heavy fabric that I can hang over the window to block out all light. Any room lights should be off at this point too, unless you have a red or yellow darkroom safety light.

 

If, like me, you’re drying your screens in a room you use for other purposes, and you can’t get away with having your room in total darkness for a few hours, you can also drape that same fabric over the fan side of your box.

With the fan on constantly, I’ve gotten away with exposing screens that have been drying for about 3 hours. If I’m not in such a rush, after an hour or so, I take the fan out, close the flap in the box, and just let the screens chill in their dark box until I need them the next day or whenever.

That’s it, if you have any questions or comments, shoot. This week’s print is going to be a bit weird, but probably won’t post until Thursday or Friday, so make sure you check back.

One of the biggest complaints I’ve heard from other at-home printers is a lack of knowledge of a good way to register a multi-color print. My process has evolved over the years, and is a mix of common sense and other folks’ methods, and I have to say it works pretty dang well. So, let’s get this class started: you’ll need, as always, your exposed screen, squeegee, and ink, but you may notice that on the table under the screen is a large sheet of mylar, which is taped down on the left hand side. Lastly, there’s a roll of Dymo tape; you’ll need to cut three pieces about an inch or so each. (If you’re unsure what Dymo tape is, it’s the adhesive label tape that goes in label makers like the one below)

Spread your ink on the screen and pull you first print onto the mylar. As long as your clamps can hold the screen well, each time you pull a print, it will print in exactly the same spot as it did on the mylar.

Line up your paper underneath the mylar until the ink on the mylar is directly over where you would like it to print on the paper. (More explanation in the next step)

Since most of the prints for The Weekly Print are the same size, I can use an earlier print to make sure each week’s print goes in the same spot. On top of that, I have lightly taped the positive that I used to expose the screen (use very low tack artist’s masking tape), and THAT is what I was lining up to the print on mylar in the last step. Once you’ve got everything lined up, peel back the mylar without losing your paper placement. Now, while holding down your paper firmly with one hand, place the Dymo tape strips flush to the edge of your paper with your other. Two on the long side and one on the short side of the paper is good enough.

(A quick tip: personally, I find the paper backing on the Dymo tape nearly impossible to peel off, so I always make sure I peel it off and set the tape aside BEFORE I make the first pull onto the mylar. It’s just less hassle that way.)

Throw down a fresh piece of paper and slide it into place so it is flush against all three of your tape strips. Then pull a print! If you make sure to always align the paper to the tape every time, each print you pull will be in exactly the same space on your paper.

OK, so anyone can do one color, but what if you want more? After printing and cleaning up after your first color, clean off your mylar and re-tape it in place on your table. Just as you did with the first color, pull the first one onto the mylar.

Now, line up the paper with your first color underneath the mylar, pull the mylar away, and adjust your Dymo tape strips accordingly. I’ve found that I can use the same three tape strips for at least three colors, just pull it up and re-place it when you switch colors.

Print away and you should have a properly aligned, two-color screenprint, congratulations! You can use this exact same method over and over for as many colors as your print requires.

If you only do smaller, less registration-intense prints, you can also hand register each print by keeping the mylar taped to your table. Pull the first one onto the mylar, just like above, roll away the mylar, print, roll back the mylar, place new paper underneath mylar, roll back mylar, print, new paper, and so on. Instead of using the Dymo tape, you just eyeball it under the mylar each print you pull. It takes a lot longer, but some people are more comfortable with it, and it’s also a good method to know if your paper does not have perfectly straight cut edges.

That’s it for this lesson, hope it was helpful! If you’re getting anything out of these home printing lessons, I’d love to see what you’ve been printing.

OK, so you’ve got a screen exposed and washed out, what’s next? Well, it’s time to get printing, the exciting (and let’s be honest, sometimes tedious) part! On the table, I’ve got my screen, of course, paper cut to the proper size, the transparency positive for one of the colors, ink, a small plastic scraper (to clean ink off the screen when you’re done), a squeegee, some spray tack, and a large sheet of clear mylar. On these smaller prints, I can fit two colors on one screen, which is why one half of my screen is masked off with newspaper.

Also just as important, in my opinion, is what’s up on the wall behind my print table. That whole wall is tacked and taped with prints, photos, drawing, and the like from many of my creative friends and acquaintances from all over the world, and is a never ending source of inspiration and visual candy while printing.

For those of you new to the screenprinting process, the screen gets clamped to the table with hinge clamps, which secure the frame to the table, but allow the screen to raise and lower in the same spot every time. The green tape is taping down a small piece of pressboard lined up with the screen frame, this slightly increases the distance between the bottom of the screen and the table, also known as off-contact.

Here, I’ve lightly taped down one of the transparencies I used to expose the screen to my paper. I’ve used a previous print to get a general idea of where on the paper I wish to print, to create a consistent placement.

First color of ink is on the screen, people! You want some good flow to the ink, but not runny. The consistency of pancake batter seems like a good match I guess.

Here’s where the mylar comes in. Tape down one edge of it to your table, then pull your first print on the mylar. Take that transparency-taped paper from the previous step, and line it up under the print on the mylar. As long as your hinge clamps are tight, each squeege pull will print on that exact same spot it did on the mylar.

I’m thinking of doing a whole separate post just on registration in the coming weeks, but here you can see that I’ve laid down Dymo tape in an L-shape aligned to the paper. Put a very light coat of spray tack down, just enough to stick the paper to the table lightly, but not glue it down. Now get printing!

OK, the first color is dry, second color is on the screen.

A very transparent yellow is my second color of this print. When printed over the halftone dots of the blue layer, it creates a nice light green color.

I didn’t take any pictures of the last color being printed, but here’s the final print, all lined up and drying on my drying rack, otherwise known as my bed.

I hope you liked my second big installment of my at-home printing process, and I hope maybe you’ve learned something. If you’re reading this, and there’s a specific question you have about the process or setup, or you have a suggestion for what step you’d like to see me cover next, please speak up.

And please, if you have been enjoying the site, or these more informational posts, remember that all of these prints are actually for sale in the Weekly Print store. Any sales would be much appreciated right now.

This week’s print might post a little later than usual: Wednesday or Thursday, so check back!

Käro requested that I do a post on my exposure setup and times and whatnot, so here we go. The picture above is probably the best photo of my unit in action.

For the light source, I’m using two 500W halogen worklights. These should be available at any hardware store for $15 (US) or less. They usually look like the picture above, but I removed the cage and protective glass. It didn’t say on the box, but some glass has UV protection properties and you want all the UV you can get when exposing, so I took it off just in case. I also removed the normal metal base on the light. Then, I built a very simple frame using scrap pieces of 2 by 4s and 1 by 2s that I had around. The work light can then be screwed into the top bar of the wooden frames and angled accordingly. The bottom of the light’s reflector is about 24 inches above the ground. The lower your bulbs are, the quicker your exposure, in theory, but you’ll also get less light coverage over your whole screen.

In the top image, the screen is sitting on a 3 inch thick slab of foam that I cut to the inner dimensions of my screen. On top of that is some black paper (supposedly cancels out some light reflection that could mess with your exposure times), then the emulsion-coated screen, then my positive (I use inkjet transparencies, a little more expensive than I might like, but they work really well), and to top it all off, a piece of glass that I took out of a cheap picture frame. The glass sandwiches the positive and screen together between the foam, giving you a tighter seal, so you don’t get any light leakage under your positive.

OK, onto exposure times. First off, the emulsion I use is Ulano QTX. I started out using Speedball Diazo emulsion, the kind that comes in their kits, but I’ve moved on. With the setup above with two worklights at 24 inches off the ground, my exposure time is 17 minutes for a screen with yellow mesh, and 14 minutes for a screen with white mesh. I’m pretty sure that I could easily lower my light source at least another few inches and I’d be OK and get lower times, but for the time being, I’m too lazy to change it and I’m getting good results so I’m happy.

One last bit of advice, don’t take my setup or exposure times as law, figure out what’s going to work out best for your space and abilities. And as much as you want to, don’t just jump into exposing something for a print, DO A STEP TEST UNTIL YOU FIND YOUR OWN PROPER EXPOSURE TIME! If you don’t know what that is or how to do it, just ask and I can do a post about it later this coming week, OK?