Types of Presses
There are a wide variety of presses available to the modern textile screen
printer. More economical machines generally have fewer print heads and process
control capabilities. Speed and ease of use as well as ink deposit and
registration tolerances are some of the things that can become more problematic
when using a cheaper or older press. A skilled operator with a solid maintenance
system can produce quality work on a less sophisticated press, but often
with a prohibitive amount of added effort.
The major distinction in press types is between manual and automatic equipment.
Manuals use manpower to move the screens from shirt to shirt and to pull
the squeegees across the screen. Autos automate these procedures but both
require manpower to get the shirts on and off the press. Manuals are usually
used for shorter runs and fewer colors as the cost of make-ready is cheaper.
Manual presses are also more difficult to use when attempting to maintain
consistency in complex or halftoned images.
There are also a range of presses designed to handle specialized tasks in
Belt presses are used to print over the entire area of the shirt by adhering
it to a moving belt that travels under the screens. Belt presses are quite
expensive and control of registration and ink deposit is often well outside
the traditional standards of the industry. Discharge inks are often used
on belt presses to control the thickness or 'hand' of the print.
All over presses are used to achieve a similar effect as the belt press.
Instead of adhering the shirt to a belt the shirt is placed over large metal
plates. Once on the plate smaller plates slide out to hold up the sleeves.
All over presses yield much greater control over the quality of print than
belt presses but are not capable of covering the garment edge to edge. A
small, usually quarter inch, gap results from the edges of metal plate. Both
of these techniques require expensive and specialized equipment and involve
a great deal of labor, so these large format prints generally cost significantly
more to produce.
The rarest of these specialized presses is the cylinder press. This is used
to create a continuous image band around the entire garment. It functions
much like the presses used to print on mugs and other cylindrical surfaces.
It is limited to printing a band around the middle of the shirt.
Many garments are decorated before they are cut and sewn on what are known
as roll presses. These presses print repeating patterns on bulk rolls of
fabric. This is the most effective way to cover the entire surface of the
garment but requires a very substantial initial investment in set up costs
and is used only for very large runs.