The Screen Printing Technical Foundation, SPTF,
has developed an Ink Calculator software package to estimate ink use for a particular
screen printed image. Accurate ink estimation helps to reduce wasted ink. The correct
amount can be purchased and, if necessary, mixed for the job. This avoids problems
with an incorrectly mixed shortfall makeup batch or storage and disposal of leftovers.
The formula uses mesh count, thread diameter, weave type, fabric thickness, image area,
squeegee and stroke length and ink viscosity. For small images the stencil thickness above
the mesh is used to determine how well the squeegee forces the mesh to the substrate and
how this affects ink use. Ink density and cost are also added if weight or cost outputs
are desired. When number of images to be printed is included, the total amount of a
particular ink color is estimated.
Output can be printed or filed electronically for recordkeeping.
It is recommended that additional computerized scanning and estimation be added to
determine the percentage of the screen used for the image. Also, estimations are better
for mesh counts above 110 threads per inch.
This software is available free to SPTF investors from the SGIA web site. Others can contact SPTF for availability.
Author: Dawn Hohl
Source: SGIA Journal, Second Quarter 1999, p. 17-20.