Want to print more T-shirts an hour? Or cut down on your ink usage? Or create different finishes for your prints? Our experts explain how to get the most out of your DTG machines (continued)
Finishing Touches
Choose your finish
It is possible to achieve different print finishes depending on the method you use to cure your pre-treat and inks. On heat presses you can use different coverings, and there are other products you can try to see what finishes you’ll get. Like most things this will require testing, but most of the time it’s well worth it as you can find some amazing and unique finishes that will make you stand out from your competition.
Luke Mitford, technical sales consultant, MHM Direct GB
How to achieve those different finishes
Gloss finish The glossy high resolution look is popular on dark retail fashionwear; printing black on black with a gloss finish gives that classy designer look. In order to achieve the best possible gloss image you will need a good quality Teflon sheet: most are a golden brown colour and have a slippery, non-porous surface. When curing with Teflon it is important you start with the DTG print still a little wet. There can be a fine line between too wet, where bleed will be apparent, or too dry, which will produce a matt, flat look. Place the printed shirt on the heat press and position the Teflon sheet over the printed area. Be careful not to slide the Teflon sheet across the image as this will cause a smudge. Close the heat press under medium pressure for your normal curing time and, once removed, you should see a nice glossy print.
Matt finish This can be achieved by using a good quality silicone curing paper. The process is similar as for gloss, but you do not need the print to be naturally wet before curing. Place the silicone paper over the printed area and close the heat press. Again, avoid dragging the paper over the image or you could smudge it. Close the heat press, but this time use only light pressure for your normal curing time. Once done, remove the silicone paper and you should see a nice flat, matt print. When curing in this way a distressed image in most cases will look better in matt rather than gloss.
Colin Marsh, managing director, Resolute DTGmanaging director, Resolute DTG
Add depth to your print
To improve print quality, use a good quality base garment. Heat press before pre-treating and give the garment a mist-over with warm water after printing as this will add an extra depth to the print.
Sean Barker, national sales manager, GS UK
Heat not pressure
DTG inks require heat rather than pressure. A tunnel, such as the dryers for screen printing, are great for curing printed garments on larger print runs and will be something that most screen printing businesses already own.
Grant Cooke, product development & campaign specialist, Xpres
Keeping Things Running Smoothly
Use a professional
Have your machine regularly serviced by the supplier because the better and more consistent the maintenance, the less down-time and engineer call-outs.
Liam White, technician, DTG Digital
Printing white ink after a weekend away
Always shake the white inks well before use – no matter if the ink is in a bottle or a cartridge. If there are ink lines outside of the printer (that is, bulk bottle style systems) always move and agitate those too, if possible. You should do this each day before printing.
Typically the white ink will settle a little in the lines inside the machine and the first prints will include a little of this separated white ink. To purge this, print a block of white ink – just big enough to get all the ink out of the print head and ink lines – then you’re ready to start production.
The longer the white ink sits, the longer you’ll have to shake: if the white ink has sat for a week or two, take an extra minute or two to get everything mixed back into solution.
Brian Walker, Image Armor
Saving ink
Any direct-to-garment system will do a regular purge procedure to keep the nozzles open, either after a certain number of prints or after a certain time has elapsed. In order to keep ink consumption to a minimum collect your jobs and produce them all together (rather than keeping the system idle and printing ten shirts every now and then).
Oliver Luedtke, Kornit
Managing environmental conditions
Both temperature and humidity levels will affect print consistency on any DTG print machine. The ideal DTG print conditions would see temperatures above 18°C and humidity over 50%. A good DTG print machine will operate well outside these ‘ideal print environments’, but levels of ink wastage, possible nozzle issues and print consistency will be improved by maintaining the recommended environment.
Top-end machines will have a degassing system to remove air particles from ink prior to reaching the print head and some have an internal humidifier system to ensure continuous print head operation. Try and keep the drying process separate to the print environment as any heat unit will have a negative effect on humidity.
Mark Smith, sales director, Adelco Screen Process
Environmental conditions out of hours
Many people make the mistake of controlling the environment only during operational hours. That is a big mistake. It can take hours for the ink temperature to adjust, and some larger machines have a thermal mass that could take several hours to acclimate. Operators need to take into account the cost of air conditioning/heating and humidity when considering the cost of overhead in DTG printing because the failure to maintain a consistent environment can cause all kinds of issues, including poor opacity caused by cold ink not flowing correctly, ink not jetting correctly because of elevated temps, large volumes of ink wasted in extended cleaning processes, and print heads permanently clogged because of low humidity.
Harvey Knapp, digital specialist, M&R
Productivity Boosters
Planning your layout
Make sure your production has a one-way flow. Everyone’s layout will be different dependent on the equipment you have and the space you have available.
An ideal flow would consist of pre-treatment; pre-treat curing; computer that loads the designs; printing; and ink curing. This is the simplest layout, but you also need to consider other factors. Where’s your stock going at the beginning of production? Do you have single heat presses, or maybe a tunnel or conveyor dryer? Do you have a packing or dispatch station that it needs to end at?
If you have a good workflow you can reduce the time wasted going from A to B to C hugely, which can be used more productively to make more prints or be invested in other projects.
Luke Mitford, technical sales consultant, MHM Direct GB
Automating workflow
Having a smooth and automated workflow system is highly recommended, particularly when dealing with the smaller job quantities usually associated with DTG output. Made-to-measure software systems are available from some suppliers that enable workflow to be automated and include back-end order processing and management. These can often be linked to a barcode system for each job to simplify and further automate the production process.
Mark Smith, sales director, Adelco Screen Process
Lower the resolution
Make sure your design is of suitable quality, but try cutting down on the resolution: you could well find that dropping this will not affect the quality, but it will speed up the print process. Do some tests and assess the difference, if any, in the quality of the prints.
Peter Wright, managing director, Amaya
Advance pre-heating
To boost productivity, try pre-treating in advance with just another quick heat press before printing. Also, group the smaller orders together to run later on in the day.
Sean Barker, national sales manager, GS UK
Optimum output
Maintaining the optimum throughput for each machine type is directly linked to the volume and type of work specific to each of our customers. DTG print machines like to run continuously so if you are not operating your printers all the time, try and batch your production so the print line/lines are operating on a constant basis from start-up. If you are running many different types of garment you can increase productivity by batching garment types and reducing changeover times from one fabric type and thickness to another.
Mark Smith, sales director, Adelco Screen Process
Switch to fast-curing inks
Try using an ink which requires less time on the heat press. You can now find inks that will cure in around 45 seconds for white shirts and 90 seconds for darks.
Peter Wright, managing director, Amaya
