<b>NORTHWOODSTUDIOS: Thermal Screen Instructions</b> >

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6-Step Printing | Processing The Screen | Printing onto Fabric | Heat Setting | Printing Without a Printing Base | Multi-Color Printing | 4-Color Screen Printing | 4-Color Computer Separations

6-Step Thermal Screen Print

step11. Create Screen
Run a thermal screen with your photocopy through a thermal imager.
step22. Peel
Peel the stenciled screen from your photocopy.
step33. Frame Screen
Apply tape to plastic frame and attach screen.
step44. Apply Ink
Align the screen on your printing surface and apply ink across the top of the screen.
step55. Squeegee
Pull the squeegee toward you to make print.
step66. Lift
Lift screen and you have your print.

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Processing The Screen

Rolls: Cut the screen the required size for your image. A nine inch length of an 113/4” roll will give youa sheet of screen for a full-sized plastic frame. These sheets can be cut in halves or fourths for small frames. A nine inch length of 173/4” roll will give you a sheet for a full-sized frame plus a sheet for a half-sized frame.
Place the screen, rough side of the screen facing up, smooth side down against your artwork. The smooth (plastic) side of the screen must touch the black carbon of your drawing or photocopy. Use an acetate carrier to feed the screen through the copier. You can make your own carrier by folding down3/4” across the top of a white sheet of paper and inserting the top of the screen in the fold.
For large images the width of the rolls is too wide to fit in a thermal copier opening. Fold the extra width (half on each side) over a sheet of white paper placed in back of the artwork, and use a carrier to feed the screen through the copier. Now you can image the full width of the image area on the thermal copier and use the folded areas as a margin for the ink when printing the screen.

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Printing onto Fabric

Follow the instuctions for printing the screen, substituting water-based textile paint.

 

Heat Setting the Dried Print for Permanency

Place a light piece of fabric, paper, or wax paper over your imaged fabric design and then use an iron or a heat press at the “cotton” or “highest” setting to go over each square foot for about 30 to 60 seconds until the cover fabric, paper, or wax paper, but not your imaged fabric design, lightly scorches. Avoid fabrics that will melt or scorch easily.
For best results print a darker color on a light or medium colored fabric. The color of the fabric will show through when using a light color.

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Printing On A T-Shirt Without a Printing Base

  1. Crease the center of the T-shirt and mark the top and bottom of the frame with a pencil at the center of your image.
  2. Place a paper between the front and back of the shirt to prevent the paint form soaking through both layers of cloth.
  3. Align the center marks of the imaged frame with the center of the shirt.
  4. Print on a clean smooth surface.
  5. Dry thoroughly before heat-setting.
    *If you use a T-shirt printing base, attach the plastic frame to the hinged portion and follow the directions for placing the shirt on the board.

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Multi-Color Printing

For multi-color printing, a design is usually separated so that each color is printed with a different screen. Some common methods of art separation are tracing, blocking, cutting, or computer separation. The separated screens are printed one at a time, with each specific color aligned on the printing surface to produce the finished composite.

Preparing the Artwork

  1. Draw at least three small crosses, one each in the top left, right, and bottom left or right margins. These are your registration marks.
  2. Trace the outlines for the lightest color you will print. Fill in the solid areas for this color. Remember to trace the crosses.
  3. Repeat Step 2 for each color.
  4. Make a photocopy of the artwork for each color.

Preparing to Print

  1. Choose a squeegee and spatula for each color of textile paint or ink that you will use.
  2. Use post-it notes or tape on the area of the shirt where the crosses will be printed.
  3. Repeat Step 2 for each color.
  4. Check the screws on each arm to be sure they are tight and the frame is held firmly in place.

Printing

  1. Squeegee the lightest color first. You do not have to wait for this color to dry before printing the next color.
  2. Turn to the second color and lower arm. Check that crosses match the first color crosses. Print second color.
  3. Repeat Step 2 with third color.
  4. Repeat Step 2 with fourth color.
  5. Remove post-it notes or tape from shirt. You may want to block off crosses with tape on the plastic side of the screen so that you do not have to add post-it notes to each shirt.
  6. Remove shirt carefully from platen board and allow to dry before heat-setting.
  7. Wipe board, if necessary, before slipping next shirt in place.

Preparing the Screens

  1. Image each copy on a separate screen in your thermal copier. Follow the artwork placement for each screen. If all the color is at the top of your design, image the top of the screen.
  2. Tape each screen to a plastic frame.

Preparing the Printing Base

  1. Check your registration by printing on paper first.
  2. Prepare platen board with an adhesive spray or plan to hold the shirt in place with a large rubber band around the bottom of the board.
  3. Slip T-shirt, bottom first, over the printing base and secure so that the T-shirt does not slip.
  4. Attach printing frames to the printing base with image upside down. Start with the lightest-color frame and proceed to the next-lightest color, attaching a black outline frame last.
  5. Adjust frames in the printing base arms so that the crosses will print directly over each other. You may want to tape the line drawing to the T-shirt for this placement.This is a 4-screen color separation of a Dover line drawing (1) that was traced to obtain 3 fill colors (2, 3, 4). After making a photocopy and screen of all four separations they can be mounted and aligned on a 4-color printer and each screen can be printed in any desired color to obtain single or multiple copies of this 4-color design. Black, Orange, Green, Blue

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How To Screen-print In 4 Colors with Thermal Screens

Preparing the Artwork

Choose a design that you would like to print in four colors, and place an “x” or a circle in each corner of your design, for registration, then make four copies of that design. You might want to make an extra copy on which you can experiment to determine were you want each of the colors.

Color Separation

Some common methods of art separation are tracing, blocking, cutting, and computer. You may find it convenient to use all of the first three methods. Computer Separation using various software programs, such as Adobe Photoshop, will enable you to come up with your design separated into the four components. Print them out on your laser printer, if available. If not, you must make a copy so that carbon toner is placed on your designs. This toner is used in practically all copiers, if not all, and also in laser printers (but not in inkjets).

You are now ready to make your screens. You need some thermal screen and a thermofax, and a frame on which to mount your prepared screens. Your designs will be melted off the plastic side of the thermal screen, allowing ink to be squeegeed through in only those places desired.

In that your imaged screens need to be positioned so that your picture is printed properly, you will need a printing base. With thermal screens, the large metal machines are not necessary. Light wooden models are available for a nominal cost that will allow you to register your screens.

If you are going to print on textiles, set up your registration by printing first on paper to get your alignment with your four registration marks on each of your screens, this is easier than you might think.

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4-Color Computer Separations

SCAN / ADJUST / CONVERT

  1. Scan image into grayscale
  2. Adjust levels (brightness/contrast); convert to bitmap to create a total contrast image
  3. Convert to CMYK

FILL IN COLORS

  1. Use paint bucket and/or paint brush to fill in each 4 colors
  2. In colors window, use 100% of each either CMY or K for each color
    (Note: Make sure black is 100% black in info window)

PRINTING

  1. Page Setup: Choose "Print Registration Marks”
  2. Print: Choose :Print Separations”

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