How to Put Iron-On Letters on a T-Shirt Straight
Crooked iron-on letters are the most visible application mistake. Even a slight angle or uneven spacing is immediately obvious because text is something our eyes are trained to read precisely. The good news is that getting letters straight is a matter of preparation, not skill. Measure, mark, and tape before you press.
The Measuring Method
Lay the shirt flat on a hard surface. Find the centre line by folding the shirt in half vertically, aligning the shoulder seams and side seams. Press a light crease or mark the centre with a small piece of tape at the top and bottom.
Measure from the collar seam down to your desired starting position. For a chest placement, this is typically 8-10cm below the collar seam. For a back name placement, 10-15cm below the collar seam. Mark this height on both sides of the centre line.
Place a strip of masking tape or painters tape horizontally across the shirt at your marked height. This tape line is your baseline. Every letter will sit on this line. The tape will peel off cleanly after pressing without leaving residue.
Spacing the Letters
If you are using individual iron-on letters, spacing matters as much as straightness. Print your text at the correct size on a piece of paper first and use it as a spacing guide. Place it under the shirt (if the fabric is thin enough to see through) or above the tape line as a reference.
For DTF transfers where the entire word or name is printed as one piece, spacing is handled in the design file. Upload your text as a complete image rather than as individual letters - this eliminates spacing problems entirely.
If using individual letters, space them by eye from the centre outward. Find the centre letter (or centre gap between two letters), position it on the centre line, then work outward left and right. This keeps the text centred even if your spacing is slightly uneven.
Pressing Technique for Text
Once positioned and taped, cover with parchment paper and press at the correct temperature for your fabric. Press each letter or section for the full recommended time. Do not slide the iron, especially with individual letters - sliding pushes the letters out of alignment.
For long text (names, slogans), press in sections from the centre outward. Each section gets its own full press time. Overlap the sections slightly to avoid cold spots between letters.
Peel the tape after the carrier film has been removed and the design has cooled. The tape served its purpose as an alignment guide and is no longer needed.
Common Alignment Mistakes
Eyeballing without measuring: it feels straight but it is not. Always measure from the collar seam and use a tape baseline.
Using the shirt neckline as a guide: necklines stretch and distort. Measure from the shoulder seam junction instead.
Pressing on a soft surface: ironing boards, bed surfaces, and carpet cause the shirt to shift during pressing. Use a hard, flat table.
Not accounting for the design weight: text that is optically centred on the shirt should be positioned slightly above the physical centre. The visual centre of a garment is roughly 40% from the top, not 50%.