Three settings, one goal
Density is the spacing between two rows of stitches in a fill or a satin: 0.35 mm means one centimetre receives 28 rows. Underlay is a first pass of light stitches (contour, perpendicular rows, zigzag) that flattens the fabric and gives the fill a foundation: without it, the stitches sink into a soft fabric and the fabric shows. Pull compensation widens every shape by a few tenths because the thread, as it tightens, pulls the fabric inwards. All three depend on the fabric.
The table
| Fabric | Fill density | Satin density | Underlay | Compensation | Stabilizer |
|---|---|---|---|---|---|
| Twill, heavy cotton canvas | 0.35 mm | 0.35 mm | Contour + tatami | 0.20 mm | Tear-away |
| Piqué polo | 0.38 mm | 0.38 mm | Contour + cross tatami | 0.30 mm | Cut-away |
| Jersey T-shirt | 0.40 mm | 0.40 mm | Cross tatami, zigzag under satin | 0.35 mm | Cut-away, light |
| Sweatshirt, fleece | 0.40 mm | 0.38 mm | Tatami + water-soluble topping | 0.30 mm | Cut-away |
| Structured cap | 0.38 mm | 0.38 mm | Contour + tatami | 0.25 mm | Cap tear-away |
| Leather, faux leather | 0.45 mm | 0.45 mm | Contour only | 0.15 mm | Tear-away, leather needle |
| Terry, towels | 0.35 mm | 0.35 mm | Tatami + water-soluble topping | 0.30 mm | Tear-away + topping |
These values are those of the reference fabrics built into the studio; choosing the fabric at the Size step applies them to every object. They were tuned on a Tajima with 40-weight polyester thread; rayon thread needs 5% less density, 60-weight (fine) thread 10% more.
The density test: stitch once, know for good
Every machine, every thread and every fabric shifts these values a little. Rather than groping around, stitch the studio's density test (Tools ▸ Density test): a row of filled circles, a row of satin rings and a row of fill + border, at several labelled densities (0.30, 0.35, 0.40, 0.45, 0.50 mm). Look at it in raking light: the right density is the widest one that does not let the fabric show. Enter it in "Global density", which multiplies every spacing in the design, and save the fabric as a reference.
Symptoms and their causes
- The fabric shows between the rows: density too wide, or no underlay on a soft fabric. Go from 0.40 to 0.35 or add tatami underlay.
- The design puckers, the edges lift: too dense, or no cut-away stabilizer on jersey. Widen to 0.40 and change the stabilizer.
- The satins are narrower than expected: insufficient compensation. Go to 0.35 mm on stretchy fabrics.
- Thread breaks in dark areas: overlapping fills. Enable "automatic holes" so that the fill underneath leaves room for the one on top.
- Skipped stitches, loops underneath: tension and needle, not the file. New 75/11 needle, 60-weight bobbin thread.
Frequently asked questions
What is the default density?
0.35 mm with tatami underlay, the studio's value, tuned on real embroidery. It is a starting point, not a truth.
Density in lines per millimetre or in millimetres?
The studio uses the spacing in millimetres (0.35 mm). Some software talks in lines per millimetre: 0.35 mm ≈ 2.9 lines/mm ≈ 7 lines per quarter inch.
Does underlay add many stitches?
10 to 20% on a fill, less on a satin. It prevents a failed design, which costs more.
Go further
The studio is free to draw, open and check designs. Your first machine file takes five minutes.
Updated 2026-09-24.