“How To” with Heat Presses
Beyond transfers, take a look at what processes can be achieved with a heat press
Published in Printwear Magazine, June 2010
With consumers becoming savvier and demanding more creatively decorated apparel, the standard screen print just isn’t going to turn heads anymore. You might ask yourself, “How can I increase creativity and offerings to my customers without investing in large amounts of equipment and software during these challenging economic times?” The answer is simple – the heat press machine.
The heat press machine has been around for years – not too much has changed in terms of its dynamics, but a whole new world of opportunity has opened up to its various uses.
For years the heat press was used to apply heat transfers, and heat transfers alone, to T-Shirts, hats and other garments. But with tremendous advancements in printing technology over the past 10-15 years, people have found new uses for the age old heat press. With the advent of digital direct to garment printing, heat presses have become essential components of the curing process.
Not only is the heat press being used for DTG printing, but because of tumultuous economic times and consumer demand for unique multi-media applications, screen printers are using equipment (i.e. heat presses) they currently have laying around in their shops and are finding new ways of using them for embellishment.
To succeed in today’s environment, screen-printers need to be creative and their products must stand out amongst a sea of “ordinary”. Consumers are looking to spend their dollars on items that are original and unique – items they feel reflect their own individuality. More and more screen print shops are turning to heat press machines because they are finding that using a heat press in conjunction with screen-printing gives their products an edge over the competition.
In certain cases, using a heat press can also cut down production time. In some screen-printing processes, a heat press can replace the use of a tunnel dryer to cure inks. Where a tunnel dryer can take 3 minutes for a single garment to pass, that same garment can sit under the heat press for 15-20 seconds and achieve the same results – case in point, discharge printing. Later, we will take you through a step-by-step process of how to do a discharge print using a heat press instead of a tunnel dryer.
To give you an idea of just how effective a heat press can be in expanding screen-printing capabilities, we will walk you through a few simple processes that have incredible results. To begin, it is of utmost importance to invest in a quality heat press. A good heat press provides even and consistent heat and pressure across the entire platen because heat and pressure are key elements to a successful application of any kind.
How to Use a Heat Press to Cure a Discharge Print:
1. To mix the colored discharge ink, first add a non-corrosive water based pigment into the discharge base. Then add approximately 6% of ZFS (Zinc Formaldehyde Sulfate) thoroughly into the discharge base. For a less intense discharge look, add a smaller percentage of the powdered agent into the base. Place your garment on the platen and screen-print the water-based discharge ink.
2. Let the garment sit for 3-5 seconds and then place it under a flashing unit for approximately 12 seconds to remove any excess moisture. You can increase or decrease the amount of time under the flash unit depending on how intense and even you want the color distributed across the graphic. The longer the garment sits under the heat the more color will show up in the graphic. We left our garment under for 12 seconds to allow for color variation.
3. Move the garment onto a heat press machine and place a Teflon sheet over the design. Set machine to 350 degrees, 40 lbs, 12-14 seconds (settings may need to be adjusted depending on the heat press) and engage the heat press. The level of discharge can be controlled in this process by adjusting the dwell time. The longer the dwell, the greater the discharge effect.
4. Once cycle is complete, peel the Teflon sheet off of the finished garment.
Textured Palette Processes:
To most screen-printers, the thought of using a textured palette is completely counter-intuitive. Standard procedure requires making sure your palette is completely flat prior to printing. However, times have changed, and “standard” is not going to stand out and be noticed. A textured palette allows printers to create completely unique and original prints. No two shirts will ever look exactly the same. By using a textured palette, the printer is letting go of some control over the process – so every print will come out a little differently. Each one will be one-of-a-kind.
How to Create a Textured Palette:
1. Cover the platen with palette peel to protect the platen. Spray the palette peel with adhesive and place a piece of crinkled transfer paper on top.
2. Cover the crinkled paper with palette peel and then tear excess peel off.
How to Create a Textured Discharge Print:
1. Create a textured palette
2. Repeat steps 1-7 of the “Discharge” section above. To create the above print, we used a dischargeable colored ink during Step 1. The combination of the textured palette, dischargeable ink and the heat press create gorgeous halftones and color variations that will be unique to each print.
How to Create a Textured PVC-Free Based Flock Foil Combo:
1. Create a textured palette
2. Build a thick stencil on your screen in order to achieve a thick deposit of ink on your garment. For this exercise, we are using a PVC Free special effects plastisol based ink. Once printed, send the garment down a tunnel dryer to cure the ink. Typical curing temp is 320 degrees for 90 seconds – however, settings may vary.
3. Once inks are fully cured, place the garment onto a heat press to apply the foil. Set the heat press for 350 degrees, 15 lbs, 2 seconds. Lay a sheet of foil over the design and engage the heat press. When cycle is complete, peel foil off.
4. Next apply your flock. Re-set the heat press for 350 degrees, 40 lbs, 12-16 seconds and lay a sheet of flock over the graphic. Engage the heat press – once the cycle is complete, if you find that you didn’t get a heavy enough flock lay-down, go back for another full cycle.
5. Once the desired look is achieved, complete the process by running the garment through the tunnel dryer again to ensure the flock and foil are fully bonded to the ink.
The heat press machine can help cut production time while allowing you to achieve ingenuity and originality in your work – far beyond what standard screen-printing methods offer. In the processes described above, no two prints will ever come out exactly the same – each one will be unique. We do recommend doing your own testing on all of the above methods to make sure you dial in the correct settings for your specific inks, machinery and desired looks.
So, to boost your business’ creativity and offerings to customers without much investment, check out your heat press resources.
Click here to view the full article in the June 2010 issue of Printwear.