How to Screenprint or Screen Print

Screenprinting involves a number of different steps to produce the finished product. There are a number of different companies that produce and sell screen printing supplies. We have found that we prefer certain products and suppliers in our production process. You will notice we reference the screenprinting vendors that we use in our shop in this section of our site.

There is a great deal of knowledge and experience required to accurately produce high quality screenprints. If you want to know how to screenprint then you should take the time to read the information below, but keep in mind this is a very basic overview of the screenprinting process. High quality screenprinting will only come with a continous process of learning and lots of hands on experience.

Attention to detail and high quality standards are key to a succesful screenprinting operation.

• Preparing Artwork to Screenprint - The first step, and probably the most important step in the screenprinting process is preparing your artwork for production. Your artwork may contain as many colors as your screenprinting press is capable of printing. Our printing presses can print up to six colors at once, so that is the maximum number of screens that any of our designs will have. We can actually screenprint almost any color needed using full color process or 4 color process printing. If you have a design with 3 colors in it then you will have at least 3 screens needed for production and possibly a fourth screen if your are printing on dark garments that need an underlay. The color of garment or textile that you will be printing on is an important piece of information to know before you can correctly prepare your artwork for production.
  

  • Artwork Seperation for Screenprinting - All artwork has to be seperated into individual colors and then positives for each color must be produced. For Example: If you wanted to print the American flag on a black shirt you are going to need a screen for each color in the design.  Therefore you would need three screens to print the American flag on a black shirt. One screen for the red ink (stripes) , one screen for the white ink (stars and stripes), and another screen for the blue ink (background for stars). Each color will first need to be printed on a positive that will be used to "burn" or create your screen. Properly seperating designs takes a great deal of knowledge and understanding. To properly seperate artwork for production you need to be very familiar with some of the high end graphics software. We use Adobe Photoshop and Adobe Illustrator for all of our design and production. Multiple color designs must be precisely seperated with accurate registration marks so that all of your screens will line up properly on the printing press. You have probably seen registration marks before on other printed products. Registration marks usually look like  a circle with crosshairs in the center. You will use registration marks on all mulit color jobs. They will allow you to precisely line up each screen in the correct location for printing.

  • Film Positives - Positives can be printed on a number of different media types like vellum or clear film. They can also be produced with several different kinds of printers. Some screenprinters use laserjet printers and vellum to produce their positives. This is the cheapest way to produce your positives, but it will give you average results at best. We use an Epson Pro 4800 Ink Jet printer and print our positives on Chromaline Accumark film because it produces very high quality positives. The Epson 4800 printer is capable of amazing detail and accuracy. Accuracy is very important when producing positives, you will be much more effecient in the operation of your printing presses if you make sure that your positives are very accurate. It is much easier and quicker to make changes on your computer than it is on the screenprinting press.
    
    A high quality positive will be very transparent (like a clear film) and the printed areas of the film will be highly opaque allowing little or no light to pass through the printed area on your positive. The goal is to have no light pass through the printed areas of your positive. High quality film positives will give you the best results when you apply them to your screens to make the final stencil for production. The stencil is made by transferring the image form your film positive to the emulsion that is coating the screen that will be used for printing. Emulsion is a light activated chemical that allows us to create the stencil or image on the screen. UV light is used to cure the emulsion on the screens. The printed area of the film blocks the light from that specific area of the screen. The parts of the emulsion that were covered by the ink on your posistve will wash out of the screen and the areas that were not covered by your positive will have been cured by the light. The cured portions of the emulsion will not wash out. So...in a nutshell. Your positive is the media that transfers the design on your computer to the screens on your printing press. The higher the quality of your positives the higher the quality of the finished product. Quality art positives are very important to the screenprinting process.
    
  • Screens and Emulsion - It would take and entire book to accurately cover all of the information and variables involed when dealing with screens and emulsions. Therefore, we will cover the basics of screens and emulsion, as well as some of the equipment and supplies that we use at Sold Out Merch.
    
    The mesh on your screens is one of the more important variables in the printing process. Lower  screen mesh numbers allow more ink  to pass through the screen each time your squegee passes over the screen.  When we need to print larger quantites of ink we use an 83 or 110 mesh count screen. These mesh counts allows us to deposit more ink on our fabric or garment. On the other hand when the artwork that we are printing calls for fine detail or small amounts of ink we use a higher mesh count screen like a 230 or 305. Ink type, ink color,  garment or fabric type, and desired printing effect are all variables that will determine the correct screenprinting mesh to use. There are at least 20 different widely used mesh counts. They range from 17 coutn mesh all the way up to 380 mesh count or more.
    
    There are three different types of screen frames that we used for screenprinting, wooden frames, aluminum frames, and retensionable frames. Wooden frames are the least expensive (about $18 each), but as you might have guessed they also give you the lowest quality results.  The tension of your screen mesh is very important, and can greatly affect the quality of your screenprints.  Wooden frames can easily warp and generally do not hold a good screen tension or very long. If you use wooden frames we recommend only using them for one color jobs. Because of their low tension they do not hold registration well and often give you undesirable "double prints" if you make more than one stroke with your squegee.
    
    Aluminum frames are a little better than wood becasue they do not warp easily and they hold their screen tension slightly better than wood. Aluminum is a little better, but not a lot better.
    
    The main problem with wooden screens and aluminum screens is that you cannot re-tension the mesh without replacing the entire mesh portion of the screen. Most shops are not equipped or do not know how to re-tension wooden and aluminum frames. Your print quality is significantly better and registration and printing are much easier when using retensionable frames. If you only use wooden or non-retensionable alluminum frames it will be very difficult for you to consistently produce high quality results in your screenprinting operation.
    
    We use Newman Roller Frames by Stretch Devices at Sold Out Merch. In conjunction with our Newman Roller frames we use The Shur~loc Accelerator 2 re-tensioning system. The Newman Roller frames are completely retensionable. This allows us to keep our screen tension very high throughout the life or our mesh. In return we can print very detailed designs that require very accurate or "tight" registration.  
    
    

    Coating, Burning and Washing Out Screens

    Burning and washing your screens for is a very important step in the screenprinting process. First of all you have many different mesh patterns to think about before your initial setup. We use several types of mesh counts depending on the amount of ink that we want to deposit onto the garment and the type of ink used; for example: If you use artwork that has a large bold print that requires a large coat of plastisol based ink, you would use a 110 mesh screen; simply because it has larger holes and less holes per sq. inch which in turn, lets more ink pass through the screen. Conversely, if you had a smaller more detailed print and you are using a thinner plastisol ink, or water based ink, you would not need to let as much ink to pass through the screen mesh, therefore a higher mesh would be required for your print to be clear and legible; like a 230 mesh for example. 

    You will also need to coat your screens with some type of emulsion or use a capillary film. You are coating the screen with a photo sensitive emulsion or film in order to give you a medium into which you can "burn" your image that will be printed. There are a number of different suppliers that produce emulsions and capillary films. We use Chromaline and Ulano emulsions and capillary films in our screenprinting operation. You will need to use and test different emulsions to determine which ones you like best.  
    
    

    Once you have determined the screen mesh and emulsion that you want to use, you are now ready to burn your art.   First of all, you normally want to center your art on the screen; be very careful on the method you select for multi color prints, for they all must line up according to the registration marks on your image; failing to do so will cause you to have to "re-burn" your screen and waste time and materials. Once you are confident that you are ready to burn, tape your art positives to the underside of the mesh using a clear small piece of tape. You use a clear tape to prevent the tape from leaving a "burned in" image.  

    Be careful not to let your image extend outside the emulsion coating causing you to lose part of your design.  

    Different light tables require different time settings for each mesh configuration and emulsion type in order to properly burn the image. We use a Richmond SM 3000 for all of our screens. After your image is "burned in" the screen, take the screen to the wash out tank and wet both sides down thoroughly, then let it sit for approximately two minutes. This ensures that your image has time to dissolve through due to the reaction the uncured emulsion has with the water. Next you spray your screens off with high pressure water to remove the excess emulsion that is your print area until you can clearly see through every part of your design to the other side.    

    Hold your screen up to a light source to determine if you are satisfied with the result. If you are, then set aside the screen to dry before you take any further steps. Once your screen is dry, you are ready to put it on your screenprinting press.

    
    
    

    Setting Up Your Press and Printing

    When screenprinting multi-colored designs, you must make sure that all of your pallets are set up equally and aligned to ensure that your design is on the same part of the shirt for every print. Otherwise your design will be near the top of the shirt for one print and further down the shirt on the next. Consistancy in printing is very important. Quality is very importat especially when poor quality could  possibly lose repeat business from your customers. After you are confident that you have everything in order, then you can align your screen using your registration marks to ensure that the design is centered and straight on yor pallet. For multi-colored prints make sure all your colors match up accordingly making any adjustment necessary to line the design up to your standards. Next, tape of all the borders of the screen to ensure you have no ink leaking onto your garment.
    
    Once completed take a shirt and do a test print. Again, for multi-colored designs; make sure that you have your flash dryer in place and heated up to the required temp. for the garment you are printing. Also be sure your belt dryer is ready and heated up at the temperature needed to fully cure the ink on your garment before it comes out of the dryer. Like we talked about earlier; if your ink is not cured properly the image will crack and wash out; again leading to loss of your return business. If you are confident you have completed all of these steps, and your test print is satisfactory, then tape of your registration marks, and you are ready to start printing the order. After you start to print the order and run the shirts through the dryer check the first couple shirts with with a digital laser thermometer to ensure that your ink is cured and there will be no problems with the quality.