There is a couple things we have found to keep the square off the shirt
1. Pressure... really it's an art depending on the material on how much pressure will be effective enough to cure the inks and last.
2. Try things like pressure pads (pillows work the best but again it's the art of the pressure). Too much pressure with these tools will be more problematic then good.
3. When doing sublimation, tear the edges of the paper. Works amazing!
To sum it all up, pressure and timing seems to be most of the art of using a heat press. We started in the print industry using transfer heat fx printing, then moved to dtg, and now we've stepped into screen printing. The Stahl Hover presses have been a key to getting our business off the ground. Feel free to pm me if you have any questions. Blessings!
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