What is the minimum line thickness for puff print?

3 mm (0.125 in), and 5 mm (0.2 in) if you want a pronounced three-dimensional rise. Anything thinner carries too little ink to lift off the surface and will read as a flat print.

How small can text be in a puff print design?

31 mm tall (1.22 in, roughly 88 pt) is the minimum, in a bold sans-serif face. The ink expands about 20% as it cures, so at smaller sizes the enclosed spaces inside letters close up and the word becomes an unreadable block.

Why is there a maximum solid area for puff print?

Solid areas above about 10 × 10 cm cure unevenly, so the surface goes lumpy instead of smoothly raised, and a large continuous mass of raised ink flexes less than the fabric beneath it and wears badly. Break big shapes into outlines, bands or areas of negative space.

Will the preview show the raised effect?

No. The on-screen preview shows your artwork flat, so it shows placement and colour but not the height. The lift is the reason to choose puff print and it is exactly the part a flat image cannot represent — order a sample if you need to see it before selling.

Printed on the surface

Puff print

Puff print is a heat-applied ink that expands as it cures, raising your design a few millimetres off the surface into a soft, three-dimensional relief you can feel. It is the most tactile decoration we offer and it reads as genuinely premium. The trade is that expanding ink needs room: strokes, gaps and text all have generous minimum sizes, and large unbroken solid areas puff unevenly, so a puff design has to be drawn bolder and simpler than a printed one.

Minimum line thickness: 3–5 mm (0.125–0.2 in)Closer to 5 mm gives a more pronounced rise
Minimum gap between elements: 3 mm (0.125 in)The ink expands about 20%
Minimum text height: 31 mm (1.22 in / 88 pt)
Maximum text height: 292 mm (11.5 in / 826 pt)
Maximum solid area: 10 × 10 cm (3.94 × 3.94 in)
File formats: PNG, SVGTransparent background

How it works

Puff print is a design cut or printed from a specialty vinyl and heat-pressed onto the item. The material is what you are buying: it brings a physical property — height, sparkle, shine — that no flat ink can imitate, and none of it shows in a flat on-screen preview.

A foaming agent in the ink activates under the heat press and the design rises off the fabric. How high it rises depends on how much ink is there, which is why thickness is the governing constraint: a 3 mm stroke puffs modestly, a 5 mm stroke puffs dramatically, and anything thinner barely lifts at all.

White puff and metallic gold on finished garments. The raised surface is the thing you are buying, and the thing no on-screen preview can show you.

Designing for expansion

The ink expands by roughly a fifth in every direction as it cures. That single fact explains all the minimums. Two elements 3 mm apart will still be separate when they have both grown; two elements 1 mm apart will merge into one shape. The enclosed centre of a letter O will close up entirely if the stroke around it is thin and the counter is small — which is why the minimum text height is 31 mm rather than the few millimetres a cut vinyl would need.

Bold, simple, sans-serif shapes are what this method wants. A thin script or a delicate serif face cannot survive expansion in any size that fits on a garment.

A bold sans-serif beside a thin decorative face at vinyl minimums. Only one of these keeps its counters once the ink expands.

Why large solid areas are capped

A solid block larger than about 10 cm square puffs unevenly — the middle and the edges cure at slightly different rates, so the surface goes lumpy rather than smoothly raised. Large blocks are also the ones most likely to crack or wear badly, because a big continuous mass of raised ink flexes less than the fabric under it.

The way around it is to break large shapes up: outline instead of fill, add internal negative space, or split a solid mass into bands. The design keeps its scale and the puff stays even.

Do this, not that

Do

Keep every stroke at least 3 mm thickThinner strokes carry too little ink to rise.
Leave at least 3 mm between separate elementsThe ink expands about 20% and neighbouring shapes will otherwise merge.
Set text at 31 mm or taller, in a bold sans-serifBelow that, the enclosed spaces inside letters close up as the ink expands.
Break large shapes into outlines or bandsSolid areas over 10 cm square puff unevenly and wear badly.

Avoid

Thin scripts and delicate serif facesFine strokes and hairline serifs cannot survive expansion at any wearable size.
Fine internal detail inside a puffed shapeDetail below the minimum stroke width simply fills in as the ink rises.

Common questions

What is the minimum line thickness for puff print?: 3 mm (0.125 in), and 5 mm (0.2 in) if you want a pronounced three-dimensional rise. Anything thinner carries too little ink to lift off the surface and will read as a flat print.
How small can text be in a puff print design?: 31 mm tall (1.22 in, roughly 88 pt) is the minimum, in a bold sans-serif face. The ink expands about 20% as it cures, so at smaller sizes the enclosed spaces inside letters close up and the word becomes an unreadable block.
Why is there a maximum solid area for puff print?: Solid areas above about 10 × 10 cm cure unevenly, so the surface goes lumpy instead of smoothly raised, and a large continuous mass of raised ink flexes less than the fabric beneath it and wears badly. Break big shapes into outlines, bands or areas of negative space.
Will the preview show the raised effect?: No. The on-screen preview shows your artwork flat, so it shows placement and colour but not the height. The lift is the reason to choose puff print and it is exactly the part a flat image cannot represent — order a sample if you need to see it before selling.

Related methods

How we know this

Supplier heat-transfer-vinyl design guidelines — verified 2026-08-15