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The enthusiasm of the open up source and maker movements has led to quite a democratization of tools. Capabilities one time reserved for professional or academic users have become staples of our daily lives. One of the earliest tool sets that changed the world after it became democratized was printing. This happened in the 15th century and again in the 20th. Inkjet printers are then cheap that they frequently toll less than the refills of their ink. The materials they print on are besides varied and easy to learn. T-shirt transfers, stickers, business cards, transparencies, and other media are common materials for personal computer users.

Nonetheless computer printing's predecessors remain in utilise. The market for printing presses may have receded, but information technology hasn't disappeared. Of the many printing processes that continue to have utility, screen printing manages to remain a viable practice amongst professional and DIY users. T-shirts may exist the most pop option, simply there are many other uses for this venerable technique. The basic activity is expressionless uncomplicated and can be washed with surprisingly primitive equipment. As with many interesting skills, incredible results can be accomplished past learning the subtleties of the fine art.

HOW DOES IT WORK?

The fundamental concept of screen printing is to stretch some kind of tightly woven material and block specific parts of the material so that when ink (or pigment) is forced through it, the ink only passes through the unblocked portions. The blocking, or resist, creates a negative epitome on the screen of what you desire on the printed surface (Figure A). Screen printing is often called "silk screening" because silk was once the best available fabric. Constructed materials have largely replaced silk over the years, only the proper name remains.

Figure A. Only areas where ink should pass are left unblocked.

The screen maintains its stretch by attachment to a frame of some sort. Many screens are stapled or glued to a wooden frame, only in that location are lots of ways to employ metal or even plastic frames. Using a frame that won't warp or distort the screen is of import for reuse.

Most screen press techniques use a squeegee to evenly strength the press medium through the screen onto the print surface. This operation is referred to as pulling a screen since the squeegee is unremarkably drawn toward the printer for the print stroke (Figure B).

Effigy B. "Pulling" a print refers to forcing the ink through the screen with the squeegee.

Screen printing is a binary operation; if you're printing with black ink, you cannot directly print gray. Even so, special techniques have evolved to emulate fades and gradations. Instead of mixing white with black to get grey, a halftone image is created that uses proportionally sized dots to create the perception of gray, or pink from blood-red and so forth (Figure C). This method also allows for mixing colors on the print. A 50% halftone of yellowish printed on pinnacle of a 50% halftone of ruddy will create the perception of orange (Figure D).

Figure C. Halftone grays are possible with dissimilar size black dots.
Figure D. Halftone colors trick the eye into mixing colors.

Multicolor prints require a screen for each color (except for some interesting effects accomplished by mixing multiple colors of ink or pigment on the screen). A print store that prints colour images will usually accept a screen press with 4 screens bundled in a style that allows the print surface to exist carefully registered on each screen until each of the colors (cyan, magenta, yellow, and blackness are common) has been pulled (Figure E).

For this skill builder, we'll stick to printing a unmarried colour without halftones. There is a wealth of opportunities for this approach; printing labels on command surfaces, adding logos to products, making basic T-shirts, or even putting a resist layer onto a surface for etching printed circuit boards.

Figure E. A patent prototype of a multiscreen press.

MAKING THE SCREEN

Screens tin can be created with a variety of methods. You tin can pigment the resist material onto the screen by hand, yous can use a vinyl cutter to create a stencil and use it directly to the screen, or you tin utilise photograph emulsion to transfer a transparency onto the screen. Each of these methods has pros and cons. We'll do the simplest for this first screen and you tin allow your level of interest determine which other methods y'all pursue.

About art supply stores acquit basic materials for screen printing and online sources have everything you need whether you're printing for fun or running a screen printing business organization. In the interest of simplicity, we're going to utilize unremarkably bachelor materials to demonstrate the ease of basic printing. Feel free to upgrade if you're interested.

Rather than going through the process of stretching screen material to a wooden frame, nosotros'll utilize an embroidery hoop for holding our stretched screen material. In the spirit of low budget skill hacking, we can use any sheer polyester material or organza for our screen instead of commercial screen cloth. I bought a bathroom drapery at Goodwill. The results won't be every bit good as using a high thread count textile made specifically for screen press, just it volition nevertheless work. Cut the material and so that yous have a section slightly larger than the hoop. Lay the material across the smaller hoop ring, then put the larger band effectually information technology and tighten while stretching the fabric as tightly as possible. I used small binder clips to lock the cloth in place (Figure F).

Figure F. The outer hoops and clamps maintain the screen'due south stretch over the inner hoop.

ADD YOUR DESIGN

Adjacent we demand to create the fine art. We'll hand paint it onto the screen, so y'all'll want to match the art to your dexterity level. For your beginning effort, avert fine lines and stick to something bones. Impress the art out on newspaper to the same size you lot want to screen information technology. You'll need a couple inches around the art to movement the squeegee, then don't make the art bigger than half the size of the hoop.

Tape the print of the image to a solid surface so it won't move and place the screen on top of it. Use a soft pencil to trace the outline of the image onto the height of the screen (Figure Thou). We're going to utilize Modern Podge for resist. Commercial resist products are available that are meliorate for serious efforts, but that's true for pretty much every aspect of this projection.

Figure Thou. Trace the outline of the prototype onto the screen.

Our goal is to block passage of the ink through whatever tiny holes in the screen other than the ones nosotros intentionally left uncovered. We will paint the Modernistic Podge resist onto the screen to cover areas where we don't desire paint to go through. It may take multiple coats of resist to fully cake the cloth (Figure H).

Figure H. Paint the resist over all areas where ink should non pass.

Assemble YOUR TOOLS

Squeegees are traditionally safety with a business firm but flexible edge. They come in a variety of sizes, but it'southward important that the squeegee be wider than the art and so that you lot can pull the print in one motion. We tin can use a credit or society card (Figure I) as our impromptu squeegee, just anything with a firm plastic edge will work.

Figure I. Anything with a crisp firm edge, like a credit card, tin work as a squeegee.

For ink, we'll use acrylic paints. Commercial inks are available that are designed specifically for different surfaces. Screen printing ink (or paint) has to exist thick plenty so that it doesn't run when you push it through the screen.

Become READY, Go SET, PRINT!

Whatever your intended print surface will be, it's e'er a adept idea to pull a couple of prints onto paper or cardboard to get a feel for the duster, ink, and screen. Place some protective newsprint onto your piece of work area and lay downward a slice of cardboard. If things are likely to slide, tape everything in identify. To avoid blurring, it's very of import that neither the textile being printed nor the screen movement while printing.

Pulling the print is typically done in three motions; offset driblet some ink onto the screen, apply a skilful dollop and then that you lot'll accept more than enough for a impress (Figure J). Second, use the squeegee without pressure to lightly spread an even coating of ink over the fine art (Figure K). Third, printing the squeegee onto the screen above the art, hold it toward y'all at 45° and pull it toward y'all while pressing evenly, merely not too firmly, down, forcing the ink through the screen (Figure 50). Learning the right pressure level is an important reason to run through some test prints showtime.

Figure J. Add enough ink to ensure proper coverage over the impress.
Figure Grand. "Load" the screen with a light pass to spread the ink.
Effigy L. Pull the impress with a firm stroke (but not as well heavy).

Lift the screen straight off of the print. Commercial (and many domicile) screen press rigs mount the screen on a hinge then that information technology can be easily lifted up. Requite it fourth dimension to dry before touching it (Figure M). If you're printing textile ink on article of clothing, you'll demand to oestrus-prepare the ink with a heat gun before washing.

Effigy Yard. Y'all tin can print on anything your screen will lay affluent against.

Nosotros've really only scratched the surface of screen printing. For another keen projection, effort cutting stencils with adhesive-backed vinyl that y'all employ to the screen (utilize a heat gun to get the vinyl to stick). Photograph emulsions allow you to brand screens with incredibly fine item. Screen printing is a not bad fashion to get professional-looking patterns onto your projects or to do short runs of clothes, posters, or art. I hope you'll keep looking into the next steps now that yous've seen how easy it is!

Tagged make56 printing screen Skill Builders

Tim Deagan

Past Tim Deagan

Tim Deagan (@TimDeagan) likes to brand things. He casts, prints, screens, welds, brazes, bends, screws, glues, nails, and dreams in his Austin, Texas, shop. He's spent decades gathering tools based on the idea that one twenty-four hours he volition come up up with a project that has a special employ for each and every one of them.

Tim likes to larn and try new things. A career troubleshooter, he designs, writes, and debugs code to pay the bills. He has worked every bit a stagehand, meat cutter, speechwriter, programmer, sales associate at Radio Shack, VJ, sandwich maker, computer tech support specialist, car washer, desk-bound clerk, DBA, virtual CIO, and technical writer. He's run archeology field labs, darkrooms, produce teams, video stores, water ice cream shops, consulting teams, developers, and QA teams. He's written for Make: mag, Nuts & Volts, Lotus Notes Advisor and Databased Advisor.

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