Job Preparation
Nothing will frustrate and cost a printer during production quite like lack of preparation. Print production is an art that requires a rhythm and flow so that the printer can be both efficient and accurate. Production is where profit is made or lost and most often it is preparation that dictates which a printer will experience.
Job Cart
Whether you use an actual cart, a card table, or just the box your shirts came in, it is important to put together any and all items that you are going to need before you start production.
Items you will want to have ready include but are not limited to:
- Films
- Shirts
- Adhesive
- Ink
- Ink knives
- Screen opener
- Press wash
- Tape
- Pellons
- Rags
- Squeegee
The goal is to ensure that you have what you need while printing so you won’t have to stop to find it.
Pallets
Although some people think that the only consideration when it come to pallets is whether or not your print will fit on it, there is much more to consider. Just because your print can be done with a pallet doesn’t mean it should be done with a pallet. Remember that loading and unloading your garment is not only important to the accuracy of the image placement but also makes up a significant portion of the total movement a printer will make during the course of production. If a printer can reduce the time and effort needed to load and unload their garment they may be able to reduce their workload considerably.
Pallets are offered in a variety of sizes, shapes, and materials. Some pallets, like jacket and koozie pallets, are designed to work with specific substrates. Other pallets are designed to help with prints on legs, sleeves, pockets or other unique placements. Pallets are most often made of wood or aluminum but also come in composite and other materials. If printing were a dance, your pallet would be your dance floor so make sure it’s right or you might break your leg.
Pallet Adhesive
Pallet adhesive is integral to the success of any print. In order for a printer to achieve proper ink coverage on his or her garment, multiple passes may need to be made during the printing process. If for any reason the garment should move between prints the image will come out distorted and the garment will have to be discarded. There are multiple types of adhesives designed to work with specific garments or in specific printing scenarios.
Pallet Tape
Pallet tape is a thick masking tape product that is used to cover the pallet prior to printing. By guarding the pallet from the damage of heat and adhesives, pallet tape will help a printer extend the life of their printing pallets. Pallet tape is sold in large rolls and is very economical when compared to the cost of replacing costly pallets.
Press Adjustments
Screen printing presses are for the most part very basic machines. There are however a few basic adjustments that should be made before you begin production.
Off contact
Off contact refers to the distance between the screen and the substrate when the screen is in the down position. When the squeegee travels across the screen the screen mesh is stretched downward until it makes contact with the substrate and the ink is deposited. After the ink is deposited onto the substrate, the mesh should snap back to its original position leaving a clean crisp image on the substrate and allowing the screen to be raised without damaging the image. If the off contact is not correct, the mesh will not be allowed to properly snap back into place and could damage the print when the screen is raised.
Tilt
The tilt adjustment is used to ensure the off contact adjustment is consistent from the front of the print to the back. In some cases the tilt will be used to allow for slightly less off contact in areas where the printer is unable to achieve firm print pressure.
Registration
Registration is used to align each image to the pallet and/or the other image elements that will be printed on the garment. If pre-registration was performed during the exposure process, the work required to register on press should be minimal. Often printers will affix a film to the pallet on which they will be printing and use that as a template for registering the screens. This method works well but will still require a test print to ensure accuracy. Regardless of which method is chosen, proper registration will ensure that your print is placed correctly and in line with other image elements.
Printing Techniques
Those that are new to screen printing often think that the physical act of printing a garment is going to be complex or difficult. The truth is that printing is really very simple with a little direction. The key to good printing is making sure that the angle of your squeegee is appropriate for the amount of ink you are trying to deposit and the finish you are looking to achieve. A tall angle will deposit a thin layer of ink with a very clean finish whereas a low angle will deposit a thick layer creamy ink. Once you have the angle figured out, you simply need to ensure that you are able to generate the appropriate amount of pressure needed to clear the ink from the screen.
Push Printing vs. Pull Printing
Push printing and pull printing are exactly what they sound like and the choice to push or pull is totally up to the person printing. While there are some squeegees that are designed for one style or the other, most often the choice is based upon the printer’s ability to generate the needed force. Because pull printing is more taxing on the arm muscles, it is often avoided by those with low arm strength or those printing large orders.
Flooding
Flooding takes place when the squeegee is pulled across the screen with enough force to fill the open mesh areas with ink, but not so much force that the ink passes through the screen and onto the substrate. By flooding a screen the printer is ensuring that the entire image is going to appear on the substrate during the printing process. If a screen is properly flooded the printer only needs to separate the ink on the upper portion of the screen from that on the bottom during the printing process to achieve a clean and vivid print.
