![]() Then tilt the scoop coater forward so that the emulsion begins to flow toward the mesh. Tilt the scoop coater slightly backwards and place it at the bottom of the mesh on the print side (always coat the print side before the squeegee side).They don’t need to stick out very much at all just enough to stop the screen from shifting. A wooden block attached to the wall will do nicely, but even nails or screws in the wall will do. The screen should be braced (at the top) so that it won’t shift while you are coating it. Usually placing the screen at a slight angle to a wall is fine. Place the screen so that it is almost vertical, (but slanted roughly 70 -80 degrees.Let the emulsion settle so that it is equal in depth across the length of the scoop coater. Pour the emulsion into the trough of a scoop coater. ![]() Whichever type of emulsion or scoop coater is used, the techniques for coating are essentially the same. Some scoop coaters just have one coating edge that is usually somewhere in the middle with regard to “sharpness” and coat thickness. The “sharp” edge of one of these type scoop coaters will deposit a thinner coat of emulsion than the “rounded” side. Some scoop coaters have two different coating edges. There are also different types of scoop coaters. It generally has longer exposure times than the alternative, pure photopolymer emulsion, which is ready mixed. Dual cure emulsion is emulsion that is mixed with a photo sensitizer (Diazo - usually supplied with it). There are basically 2 types of liquid emulsion used in screen printing. Make sure the mesh is completely dry before coating. The screen should be suspended so that it is supported by the frame and air is allowed to flow freely over both sides of the mesh. Place the screen in a horizontal position to dry (either side up is ok).Rinse with low water pressure until there are no more “soap” bubbles. After you’ve lathered both sides of the mesh, flip the screen back over and thoroughly rinse the squeegee side first and then flip and rinse the print side.But you do want to be methodical about it and degrease every bit of the mesh. So, although this is a good technique, it’s fine to use a technique of your own. Note that the idea here is to THOROUGHLY clean the mesh and prevent problems. After that, use the exact same process on the outside (print side) of the screen. Next go around the inside (squeegee side) of the frame, one stroke around all four sides going counter-clockwise, then the same going clockwise. Then scrub the whole screen at approximately a 45 degree angle, switch (90 degrees) and scrub in the opposite direction. Next scrub the mesh horizontally left to right working in rows from top to bottom then vertically scrub up and down working in columns from the left side of the screen to the right. Then do the exact opposite, that is, small, clockwise circles working from the lower right to upper left corner. A good technique is to start at the upper left-hand corner, using small, counter-clockwise circular motions and moving left to right in descending rows towards the lower right-hand corner. Using a scrub brush, (the long bristle kind with a handle is recommended, but almost any kind will do) methodically scrub the ENTIRE surface area of the mesh, starting with the inside, or squeegee side, first. ![]() It is possible to use a dishwashing detergent (like Dawn®) but a degreaser designed for degreasing silkscreens is best because it will not contain dyes, perfumes and other things you don’t need (those things can leave residue).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |