An important aspect of screen printing a T-Shirt properly is getting the print straight on the shirt. A print that is not square and runs up or down hill will surely end up in the rag pile.
Once you line up the screen to the image to be printed, you should be ready to print a full run of shirts without the screen moving.
Then it is as simple as putting each shirt on the platen in the same place to get a consistent placement of the image.
Setting a standard measurement to use is a good rule of thumb. We’ll use the bottom of the shirt collar as a starting point to measure from. As an example, we’ll place an image on the front of the shirt “3 inches from the bottom of the collar”. This means we have measured and placed the top of the image to be printed 3” below the collar. We will tape the film positive in place and use it to line up the screen. Now that you have a shirt placed on the platen properly and have determined where the image will be placed, we'll demonstrate how to set up the artwork for printing. We are going to cover lining up a single color print job.
Step 1. Place the film positive artwork on the shirt. Measure 3” from bottom of the collar to the top of the image. Center the art on the shirt. You can center the artwork on the shirt either visually or by measurement.
Step 2. Next, place a T-square under the image to make sure the image is square with the shirt. You can obtain a t-square at most office supply stores. An 18-24” t-square works best for setting up jobs on most t-shirt screen printing presses.
Step 3. Tape down the film positive on the shirt with removable tape. Be sure to use several pieces as you do not want the film positive to move once you determined the exact placement.
Step 4. Bring the screen head down and place the screen on top of the film positive so that the stencil lines up exactly. Tighten down the knobs of clamps of the print head. Each time you bring the screen down to print, it should print the image in exactly the same place on the shirt.
TIP: Before you print an entire run of shirts, check out the placement by either holding up the shirt and looking at the and looking at the print or try on the shirt and look in a mirror.