The heat press has become an integral part of the digital workshop as a companion tool for direct-to-garment printers, rhinestone machines and vinyl cutters. (Image courtesy iDek USA Inc.)

Necessity breeds invention is an oft quoted cliché, but on the flip side of that, inventiveness itself is necessary, especially in an industry where it can be seen every day through the custom clothing creations imagers bring to life. To ensure apparel decorators’ ability to achieve that creative cusp, we’re fortunate to work within a world affording wiggle room at even the machinery level, with modifications continually made to one of the most trusted staples: the heat press. Here, a few press professionals give Printwear the scoop on innovative tweaks and the applications that inspired them.

 

Under pressure

Time, temperature and pressure are the big three heat press variables, and while operators have long been able to dial in the first two, the elusive pressure element is now being incorporated into many machines’ digital controls. With this feature, manual presses can display some degree of pressure, giving pressers a higher degree of confidence in their light, medium or firmness, generally on a zero to 10 scale, says Aaron Knight, Geo Knight & Co Inc. “This technology is important because, number one, eighty to ninety percent of heat presses out there in small shops are manual presses. And by a long shot, the number one tech-support call we get is: How do I know if I’m pressing it properly?” Now, rather than estimating or attempting to translate the pounds of pressure at which you’re clamping down, people have a solid reference when following their transfer supplier’s setting instructions for pressure, Knight states, especially reassuring to new users who have yet to generate a personal feel for it.

HIX Corporation’s James Ortolani encourages operators not to worry about the pounds-per-square-inch settings that often accompany transfer papers because when broken down, the numbers don’t add up. For example, if a transfer calls for 90 PSI (heavy pressure) in a 15 X 15 press, that’s 225 square inches multiplied by 90 pounds per each one of those inches. This equals a grand total of 20,250 pounds, or 10 tons, of overall platen pressure… the likes of which no commercial manual machine on the planet is capable of, says Ortolani. 

Regarding heat press controls in the context of another consideration, Linda Woods of iDek USA Inc. brings up temperature. “Heat needs to be consistent, so it is imperative that the control includes a good industrial-grade microprocessor programmed to control heat temperature between press cycles,” she says. 

 

With digital pressure readouts, operators get a good sense of where they measure up in terms of light, medium and firmness. (Image courtesy Geo Knight & Co Inc.)

Atypical adaptations

Although today’s press operators have a more accessible means of determining the big three, these variables are no less dependant on the substrate in question, and according to Woods: “There are many novel uses for the heat press. Pannini maker (less the grill marks) is one of them, no joke. Boot brander to rhinestone bikinis, baby diaper imprints to photographs on silk scarves. We’ve seen suction rings for no-spill drinking and recognition for paintball equipment,” she reports. “Car parts to carpet swatches. If that’s not enough, try batteries and compression bras.” 

Knight notes a significant part of the heat press business today leaning toward large format, in large part due to the popularity of all-over printing. “There’s a very common trend of doing post sewn, finished garments,” he says. “You’re laying a huge sheet transfer face-up at you; you put the shirt on it, followed by another transfer on the other side. Press the whole thing and you get this wonderful print, almost everywhere.” 

The shoulder and underarm areas that don’t receive ink due to fabric wrinkles do not pose a problem, as they are considered by design, Knight points out. “They’ve actually made this a style where there are areas that are wrinkled a bit or little white lines where the fabric folded and didn’t get ink, somewhat three-D areas of the garment. So this is actually something you’ll see in stores—this distressed sublimated full-color print. It’s because a lot of U.S. makers just want to be able to print fully-assembled garments without having to sew afterward.” 

While high-end bike and sportswear requires a more involved print, cut and sew operation to produce perfect results, Knight adds that the technology side of the aforementioned process involves monstrous presses with heat at both ends. “Both sides are printed at the same time and two transfers are sandwiched around a shirt with top and bottom heat.” 

Another element thrown into this particular mix is a twin-shuttle option with a Teflon support sliding back-and-forth underneath the heat platen and allowing operators to load garments without scorched fingers. “You’re not actually loading onto the bottom heater,” Knight reports, “you’re loading onto a carrier tray, shuttling it into the press and the moment the press comes together, that’s when both sides are heated.”

When heating both sides simultaneously for the same duration, there’s no difference in printing results between shirt sides, Knight goes on. “And you can get this in a twin station format, so while one side is pressing, you can be loading and unloading the other side,” he adds. “The moment it’s finished, you already have another set of work ready to slide right into the press again.”

 

There are many variations of the similarly functioning twin- and shuttle-oriented presses, designed to fulfill needs for production heat pressing. (Image courtesy HIX Corporation)

Mod modifications

Re-popularized for all-over printing, top and bottom heat was originally designed for chunky appliqués, as the heat helps draw the adhesive on the back sides of embroidered patches into the fabric, Knight points out. Like bellbottoms, he observes several heat-press styles and functionality coming back into fashion. And as a modern wash or detailing may update an old jean with a distinguishable flare, enhanced technology—such as better magnets and electronics—serves to modernize the heat press as these features re-emerge. 

Another embellishment-driven resurgence is pop-up functionality, newly necessitated by direct-to-substrate processes. “Direct-to-garment printers have these long curing times and just didn’t want to be held hostage by the print, standing around the press,” Knight remarks. He jokes that with Americans’ attention span being no more than 20 seconds and D2 dwell times reaching beyond that to as long as a minute and a half, shirts are doomed to burn up after the operator completely moves onto other tasks. “So they wanted the press to pop open automatically, but didn’t want an air-compressor automatic expensive air-driven press, so all of a sudden, pop up kind of revived again.” 

Ortolani points out that when it comes to D2, heat pressing for the cure will produce a flatter, shinier finish. So if more of a matte look is the desired effect, he recommends running it through a conveyer dryer or employing another method. 

Brought about by the popularity of multimedia prints, a rather unconventional heat press alteration involves building one right into a screen printing set up. “Let’s say I’ve got a T-shirt that I want to screen print, flock transfer and foil transfer all on the same print. There are ways to put a heat press in line with an automatic printer,” offers Ortolani. “Picture a heat iron in that slot where a screen fits in the automatic press, that way, you can start off with a registered print and then station number two, instead of printing a second color, we might put a flock transfer on there or a foil transfer in line, and it stays in registration with the print.” 

Disabling an automatic’s print squeegee stroke to make way for a pressing station, in-line heat pressing allows for custom combinations. Ortolani additionally mentions a hoop designed to go from embroidery machine to heat press, also facilitating multimedia apparel decoration.

Always evolving to keep up with the dynamic decorated-apparel industry, it’s hard to know what kind of heat press technology will surface or resurface next. But much of the machine’s fate will be shaped by its operators, and what’s to come is only for embellishers’ creativity to reveal.