Registering a print is a vital piece of the screen printing process. Printers need to make sure that all screens align with each other and have the proper placement on a shirt. Let’s take a look at properly registering single and multicolor prints with plastisol and water-based ink.
LINING UP THE SCREEN
Lining a screen up to the film used is a great standard. To do this, simply grab the film you used for the job and place it in the center of the platen. Use the primary print color film to align screens. This should be either the white underbase or the black outline. Use whichever film gives the greatest surface area to align screens with.
Pro Tip: When creating films for a job, place registration marks 1” above the design. Include registration marks on the corners of the film too. This way, you’ll be able to ensure the film is perfectly centered on the platen. Create the registration marks at 1pt line width for a fine-tuned register.
The lines on your platen should mark the center, and you can line up the film to where you want the print to land on a shirt. Once the film is lined up, tape it down using Scotch tape. Then, simply bring the screen down on top of the platen and align the screen to the film. Repeat these steps for all screens in the job.
Now that the screens are all aligned with the center of the platen, it’s time to start registration. Let’s start with the easiest ink to register: plastisol.
REGISTER PLASTISOL PRINTS
When registering for any job, there are a lot of potential variables: off contact, print pressure, screen tension, etc. When registering any print, it’s easiest to register directly to the print. This shows a truer representation of what you’ll see when you start the print run.
First, apply platen tape and water-based pallet adhesive to the platen. Pour a small amount of the adhesive onto the platen, swipe it around evenly with a cleanup card, and send it under the flash dryer until it’s tacky. Load a shirt onto the freshly-tacked platen and add a small amount of ink to the screen.
Pro Tip: Start by adding a small amount of ink to the screen with an ink spatula.
Load a junk shirt or test pellon onto the platen. For 1-color jobs, this process is simple. All you need to do is ensure that the screen lines up with the shirt and the print is centered.
REGISTERING MULTI-COLOR PRINTS
Registering by hand works most of the time, but there are limits. Without micro-adjustments, you’ll have to tap the screen back and forth to get it exactly in register, which can take time and become frustrating. Multi-color prints can quickly turn into a challenge without micros.
If you’re looking for tight registration or want to print multi-color jobs easily, micros will help you out. Micros are knobs on the printhead that allow you to move a screen vertically and horizontally without loosening the screen clamp. If a screen is off by a hair, you can make the smallest adjustments with the twist of a knob. Micros make it much easier to register screens, streamlining the pre-production process.
Now let’s register a water-based print.
REGISTERING WB PRINTS
When registering water-based prints, line up the screens to the film, set up a junk shirt, and get ready to be speedy. Water-based ink dries out, whereas plastisol ink won’t. The more colors you’re trying to register, the greater chance you’ll have ink drying on the screens. You don’t want to have to clean out a screen before you’ve even started printing.
If you’re just registering a one-color water-based print, you won’t need to worry too much about ink drying on the screen. Simply line it up, do a test print, and check out the result.
Registering multicolor water-based jobs gets a little more complicated. You’ll need to keep the ink in the screens wet while moving through every color. Say you’re printing a four-color water-based job. Add ink to the first screen, check for proper screen alignment and registration across all colors, and print it.
Once you’re happy with the registration on the first screen, wipe out the image area on the T-shirt side of the screen before moving on. Keep a spray bottle of water nearby to spritz the squeegee side of the screen you just printed with to keep the ink moist. Register the current screen and move to the next. Repeat this process with every screen. Keep an eye on the screens as you go, wiping down the T-shirt side and spritzing the squeegee side.
Note: Shops with low humidity will need to spritz screens more frequently than shops in high humidity. Keep track of your shop’s humidity like you would a darkroom. A hygrometer can be a screen printer’s best friend.
Water-based ink is trickier to register, and you can’t step away from the press for long while the ink is on the screen. Bring your lunch and your water bottle with you for ultimate productivity.
No matter which type of ink you use, registration takes time. Proper registration marks and a little bit of patience go a long way. Once all the screens are registered, do a test print or two. Check out how close the registration is and adjust if necessary. Tape off registration marks, take a bite of your lunch and get printing.