A sewing pattern tracer that works in AR

Sttchr projects your sewing pattern onto the fabric at true size, through your iPhone or iPad camera. You trace the lines straight onto the cloth. No printing, no taping pages together, no tracing paper.

What is a sewing pattern tracer?

A pattern tracer is anything that gets the lines of a sewing pattern from the pattern onto something you can cut. Sometimes that is fresh paper, so the original stays whole and you can trace a different size later. More often it is the fabric itself, so you can chalk the outline and cut. The job is always the same. Copy every line at exactly the right size, with the grain line and notches in the right place.

The old ways to trace a pattern

Tracing paper or Swedish tracing paper

Lay a sheet over the pattern, copy your size with a pencil, then cut the copy out and pin it to the fabric. It protects the original, but it is a second round of tracing and cutting before you have touched the cloth.

Tracing wheel and carbon paper

Sandwich dressmaker's carbon between pattern and fabric and roll a wheel along the lines. It is quick, but the marks can be faint on textured cloth, hard to remove on light cloth, and the wheel perforates the pattern.

A light box or a sunny window

Light from behind makes the lines show through. It works well for paper and sheer fabric, but the box limits the size of the piece and heavier cloth blocks the light.

A projector

Projector sewing skips printing entirely, which is why so many people love it. It also means a ceiling mount, a dark room, and calibrating the image every time the projector or the table moves. See projector sewing without a projector.

And before any of these, a PDF pattern usually means printing 30 or more pages, trimming the margins and taping them into one big sheet. Here is how to use PDF sewing patterns without printing.

How Sttchr traces at true size

Sttchr does the projector's job with the phone you already own. Point the camera at your fabric and the pattern appears on it, at the size it was drafted, and stays put while you move around.

1. Pick a pattern. One from the shop, a free one in the app, or your own PDF.
2. Choose your size. One tap, and the app keeps only the lines for that size.
3. Scan your fabric. Move the phone once so it learns the surface.
4. Place the pieces and trace. Chalk the lines and cut.

There is no pinch to zoom, on purpose. Every piece is shown at its real printed size, and each pattern carries a scale reference you can match to a ruler once to be sure. Pieces you have placed stay on the fabric as ghosts, so you can lay out the whole cutting layout and check it fits your yardage before you cut. See how to trace with a tripod or freehand and how to check the scale.

Supported pattern types

• PDF sewing patterns in any sheet size. A0, A2, A4 and US letter, including print at home files you would normally tile and tape.
• Layered PDFs with one layer per size, so you can show only the size you are cutting.
• DXF files. Exports from CLO 3D, Seamly2D and Optitex land at true size with no calibration.
• Patterns from the Sttchr shop, from independent designers, ready to trace the moment you own them.

More detail in what types of patterns are supported and how to upload your own pattern.

Frequently asked questions

Is the projection really true size?

Yes. Every piece projects at its real printed size, and there is no pinch to zoom on purpose. Check it once against a ruler with the scale reference, and the app tells you any time you leave 100%.

Do I need to print anything?

No. Quick trace needs no printing at all, and it is the default. If you want a locked, centimetre accurate fit, you can print four anchor squares and lay them around your pattern.

Which devices does it work on?

Sttchr runs on iPhone and iPad. A tripod that bends at an angle keeps both hands free, but tracing freehand with the phone in one hand works too.

Is the pattern tracer free?

The app is free to download. Your first 2 uploads of your own PDFs are free, and patterns you buy in the Sttchr shop are always free to trace. Sttchr Pro gives you unlimited uploads.

Will it work on dark or plain fabric?

Yes. Turn on a light and move the phone side to side so it can read depth. If it still cannot find the surface, the app lets you place the pattern yourself, and you can switch the line color to white for dark cloth.

More in tips and tricks for a cleaner trace.