Choosing the right frame and mesh is critical to achieving quality prints. This overview looks at different frame types, mesh parameters and performance criteria, screen-preparation tips, and recommendations for ensuring long-lasting screens.
When you get different fabrics in the higher mesh counts, you will notice there are white meshes and yellow meshes, many in the same counts. Generally, whites are cheaper than the dyed/colored mesh. So why use yellow?
When exposing a positive on white mesh, especially halftones and fine lines, you may notice the edge definition and the quality of the image is rougher than the positive. This is due to light bounce. The white threads reflect light in different directions and produce soft edges on the stencil. Yellow mesh minimizes this effect and produces sharper images. This is not so critical on coarser meshes where details are bolder—i.e., for T-shirts or basic designs with flat colors. It does become critical in halftone or fine-detail printing.
Note that stencils on white meshes expose faster than those on yellow mesh fabric. You should adjust your exposures to take this into account.
Rips and tears
The following recommendations will help you deal with mesh rips and tears:
• Avoid pressing against the mesh along the frame and glue joint, as this can cause the mesh to delaminate from the frame. The adhesives are very strong side to side, but will give way when pulled up (shear vs. tear strength).
• Pinholes or small rips in mesh can be carefully taped on both sides. Thin gold Mylar decal material makes good patch material (Figure 4), and stencil place ment and care can allow the printer to work around a hole and extend the useful life of the screen.
• Don’t print over sharp edges of plastic, metal, glass, or paper, or you will wear out the stencil, and the screen mesh. Tape over wear points on the underneath side of your stencil to protect screens from ripping.
Mesh opening vs. ink flow
The amount of opening between the threads in a screen is one of the factors that determine the ink flow through the screen. As mesh counts get higher, the thread diameter also comes into play. New mesh technology has produced finer threads, allowing larger openings between them, even in the higher mesh counts.
Screen care tips
The following screen care suggestions will help you prolong the life of your screens:
• Once properly tensioned, new mesh should be chemically scrubbed and degreased before use, to allow the stencil to adhere properly.
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