Nine out of ten DTG complaints that land on my desk trace back to two pieces of equipment: the pretreat sprayer and the heat press. Not the printer. Not the DTG ink. Not the RIP software everyone loves to blame. The boring stuff. And boring stuff is where most shops quietly bleed money, one reprint at a time.
I’ve watched people drop five figures on a machine and then wreck the output with a clogged spray bottle and a press left on whatever setting the last operator used. So here’s the unglamorous truth, mistake by mistake.
Pretreatment Is Not a Formality
The number one error is simply using too much. A shirt should feel damp after pretreat, never soaked. When you flood it, the ink floats instead of bonding, whites go grey and flat, colors lose punch, and the hand feel turns stiff enough to stand up on its own. On light garments, that excess moisture plus press heat is also a direct route to scorching and yellowing. More pretreat does not mean brighter prints. It means mush.
Uneven application runs a close second. Clogged nozzles, inconsistent passes, drips, puddles at the edges. You get patchy whites, haloed edges, mottled blacks, and a visible rectangular ghost where the pretreat landed heavier. If you’re doing volume, a proper pretreat machine pays for itself in consistency alone. If you’re spraying by hand, slow down, keep a steady overlap pattern, and clean that nozzle like your margins depend on it, because they do.
Then there’s the fabric mismatch. Pretreat is not one-size-fits-all. Cotton, blends, and poly-heavy garments want different chemistry and different heat. Treat a poly blend like a 100% cotton tee and you’re inviting dye migration, ghosting, and a print that shifts color after the first wash.
Printing on wet pretreat is another classic. If you can feel moisture, it’s wet, and wet means bleeding, mottling, and inconsistent ink absorption. Dry it fully at a low temperature. Blasting it with high heat to speed things up can prematurely activate the pretreat and leave you with scorched whites before the ink even touches the shirt.
And stop eyeballing your dilution ratios. Some pretreats are ready to use, some need cutting, and guessing wrong gives you either weak, washed-out whites or a shirt that feels like cardboard. Follow the spec sheet. Write the ratio on the jug.
The Curing Mistakes That Cost You Customers
Under-curing is the silent killer. The print looks fantastic coming off the press. It looks fantastic on the shelf. Then it goes through five washes and cracks, fades, or washes clean out. Guess who gets blamed? Not the press setting. You do. If your prints fail in the wash, you didn’t cure them. Period.
Stop trusting the dial on your press. Temperature controllers drift, platens run hot in the middle and cool at the corners, and “350” on the display is often nowhere near the actual surface temperature. Buy an infrared temp gun and verify. Then verify again next month.
Over-curing has its own signature: yellowed whites, scorched edges, a plasticky hand, and prints that crack when you stretch them because the ink has been cooked brittle. There’s a narrow window between underdone and burnt, and the only way to find it is measurement, not vibes.
Pressure matters more than people admit. Crank down too hard and you flatten the ink into the weave, change the texture, and sometimes imprint the top platen right into the print. Too little and you never get proper contact. Light, even pressure. Just enough.
Pre-press the garment. Always. It pulls out moisture and wrinkles, gives the ink a flat surface to sit on, and prevents the ghosting and uneven cure that come from pressing a lumpy, damp shirt.
Then, the one that gets overlooked constantly: don’t stack hot shirts. Trapped moisture between freshly pressed garments causes dye migration on blends and lets prints stick to each other. Let them cool on a rack. It costs you a few feet of floor space and saves you a pile of returns.
Cure time and temperature are fabric-specific, not universal. Cotton typically wants around 320°F for 30 to 60 seconds. Blends and poly want lower heat and more time. Learn your combinations and write them down, because “whatever worked last time” isn’t a process, it’s a gamble.
Finally, test. Wash test every new fabric and ink combination before it goes into production. Five washes, hot water, no fabric softener. If it survives that, it’ll survive your customer.
The Fix Is Usually Cheaper Than the Reprint
Here’s the part nobody wants to hear: most of these problems aren’t solved by a new printer. They’re solved by a better pretreat, a sprayer that doesn’t clog, a temp gun, and twenty minutes of actually dialing in your press. That’s it.
If your whites are dull, your darks are cracking, or your inbox is full of “it faded after two washes” emails, the answer is probably sitting in your pretreatment station and your heat press. Fix the boring stuff first. The printer was never the problem.