Screen Printing FAQ

Q: What mesh should I use?
A: Glitters = 25
Foil Gels, High Density = 60-110
Athletic numbering and lettering, whites, high coverage = 110
Detailed Spot Color = 160-200
Overprints over a base plate, industrial printing = 195-355
Higher end halftone 4/C process, industrial printing = 300-305


Q: What ink should I use?
A: With the series of inks in the marketplace such as multipurpose, low bleed nylon, polyester, water-based, discharge and the list goes on. Choosing the proper ink can save time and money.
Multipurpose inks. Can be used for printing 100% cotton or 50/50 poly cotton with no modifications. If printing, direct to nylon jackets a catalyst must be added.
Low bleed or polyester inks. For printing on 50/50 blends, 100% polyester, or dye migrating fabrics.
Nylon inks. For printing on open mesh jersey nylon jackets, catalyst is normally recommended.
High opacity inks. For printing , super opaque maximum coverage on dark garment.

Q: At what temperature should my dryer be set?
A: Plastisol ink needs to cure at 320° throughout the entire ink deposit. This is accomplished by temperature and dwell time. Depending upon type of dryer you would raise or lower temperature and adjust belt speed. A quick check for curing is to stretch your print after it comes out of the dryer. If the print does not crack then your print is most likely cured. If the print does crack your garment is under cured. You can slow your belt speed down and repeat the process.
The best way to determine if they garment is cured is a single garment wash test.

Q: When exposing what causes my positives to stick to the screen?
A: Insufficient drying of the emulsion or high humidity, for best results coated screen should be thoroughly dry, use of a dehumidifier is helpful.

Q: What causes pinholes and the stencil to breakdown?
A: This is a very common problem and can be avoided.
list of common causes:

• improper degreasing and final rinse
• under exposed screen, not enough burn time, week bulbs
• uneven coating, damage scoop coater, screen mesh tension
• improper mixing of emulsion, diazo bad
• exceeded shelf life of emulsion
• emulsion not dry before exposure
• dust or dirt on coated screen
• dust or dirt on positive or exposure glass

Q: Screen selection wood, aluminum, or re-tensioning?
A: Frames come in a wide variety of sizes and mesh counts. Most common is a 20 x 24 wooden frame.
Standard wooden frames are inexpensive and will hold tensions reasonably well, however they do not clean up well and have a tendency to warp. The frame must be re-stretched on a stretching table.
A rigid aluminum frame will stay flat and will clean up well. Also must be re-stretched on a stretching table.
Self tensioning frames with a little maintenance are forever. They clean up well and you can re-stretched and retention yourself. More expensive and is a challenge to learn to stretch and maintain.

Q: there is liquid on the top of my ink. What causes this?
A: With time some inks will settle or separate producing a liquid to form on top, it must be re-blended well before using. If used, and not blended well, the ink will not cure properly and will wash out.

Q: What is the process for reclaiming a screen?
A: Reclaiming a screen allows you to remove the stencil and use it for another job,
Supplies needed: ink wash, emulsion remover, haze remover and degreaser.
First, remove all excess ink and remove any tape on the mesh and frame.
Next, use an ink degradent or press wipe and remove all remaining ink and rinse with cool water.
Spray emulsion remover on both sides of the frame using a scrub pad or brush on both sides of the frame, rinse the image off with cool water. An electrical power wash unit is helpful for this process.
Spray haze/degreaser on both sides of the frame using white scrub pad scrub both sides of frame.
Final rinse with cool water low-pressure.

Q: When this flash curing used:
A: For the screen printing process flash curing is a major part and is done for several reasons.

1. Pre-shrink a garment before printing. On some nylon and polyester or garments where the registration is tight. Flash, and leave it a little longer than what the actual flash time would require.
2. To enhance ink coverage, print the first color place under flash unit until it's just dry to touch. Let the print cool and then print same color again.
3. To avoid muddy prints, when printing multicolor one ink sits directly on top of another ink colors. The ink will mix, resulting in a muddy appearance to prevent this flash after each color.
4. To avoid pick up on the screen when printing multicolor jobs. By flashing between each color. the screen will stay clean and reduced possibility of shadowing.