Impressions - June/July 2016 - 54

The biggest
challenge for
heat printing
oversized
transfers is the
size limitations
of some heat
presses.
process, both sides of the garment are heat
printed at the same time by laying one
transfer (ink side up) on the heat press'
lower platen, then laying the garment on
top of it. Next, lay the second transfer
(ink side down) on the opposite side of
the garment, press for 30-40 seconds at
400˚F-425˚F with medium pressure and
the results are amazing.
Large-format, inkjet printers have paved
the way for sublimation printers to produce
seam-to-seam designs covering the entire
front and back of a garment. The fabric
must be 100% polyester or have a high
polyester content for the ink to transfer.
Plus, sublimation transfers only work on
white or light pastel colors due to the
ink's transparency.

Press size insights
The most common heat press sizes on the market are 15" x 15" and 16" x 20". Oversized heat presses
are generally in the 20" x 25" to 40" x 48" range or bigger. The 20" x 25" size is ideal for big chest or
back prints, but the 30" x 40" or 40" x 48" size is needed for allover prints that run from seam to seam
and for graphics that extend to the sleeves of a garment.

After applying with the
required time and pressure,
peel the transfer paper back in
a smooth, continuous motion.

Application Tips
The biggest challenge for heat printing
oversized transfers is the size limitations
of some heat presses. For best results, buy a
jumbo heat press to apply oversized transfers in one pressing. Another option is
to use a smaller heat press and apply an
oversized transfer in two steps: applying half
the transfer and then sliding the garment
to apply the other half.
This method takes practice. Also, it's
recommended to use a hot-split transfer,
since the ink re-melts and doesn't leave a
noticeable "line" in the design after sliding
the garment over for the second heatpress application.
When applying an oversized transfer, it's
important to have a pressure-adjustment
mechanism to increase the clamping
pressure since the larger heat element
will require more downward force to
properly apply the transfer. Oversized
pneumatic presses are ideal since they rely
P.54

on an air gauge for repeating successful
pressure settings.
For example, use 40 pounds per square
inch (PSI) for light pressure, 50 PSI for
medium pressure and 60 PSI for heavy
pressure. Note that this is airline pressure
and not platen pressure.
It's a myth that a heat press can produce
60-90 PSI of downward pressure. Manual
or small-format air machines actually
only produce clamping pressures between
5 and 7 PSI of actual platen pressure,
which is adequate for most heat-transfer
applications. Large, oversized heat presses
produce even less PSI of downward force,
so you may need to experiment with
different time, temperature and pressure
settings for best results.
Heat printing oversized designs has
introduced the challenge of producing thousands of them in a short period
of time. To help meet high-production

i m p r e s s i o n s m a g . c o m JUNE/JULY 2016

requirements, shuttle transfer presses
have been introduced. With these highproduction systems, gar ments are
continuously loaded on the machine's
lower platen and shuttled under a heat
platen to be pressed.While one garment
is being pressed, a blank garment is loaded
on the second platen to be shuttled under
the heat platen next. Several manufacturers
offer this technology.
For industrial oversized heat-transfer
applications, heat-roller technology is available to print materials roll to roll.These
heat-transfer machines feature two large,
heated steel rollers that produce highpressure contact between the substrate and
the transfer material.The combination of
the heated roller and extreme pressure
allows for a quick heat-transfer rate and
can be useful for transferring continuous
designs onto large bolts of material.
Whether you choose to use jumbo

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Impressions - June/July 2016

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