Underlay is the hidden layer of stitching that goes down before your visible top stitches. Most beginners ignore it or use a single default setting. Experienced digitizers treat it as the foundation of the entire design — because it is.
What Does Underlay Do?
- —Compresses fabric pile (fleece, terry, velvet) so top stitches sit on a flat surface
- —Stabilizes the fabric within the hoop to reduce distortion
- —Locks the stabilizer to the fabric so they move together
- —Provides a base for top stitches to grip, preventing sinking or shifting
Edge Walk Underlay
A single row of running stitches placed just inside the outer boundary of a fill or satin area. It's the lightest underlay type and the most common first layer.
Use it for
- —Outlines before satin columns
- —Light woven fabrics that don't need heavy compression
- —First layer beneath other underlay types
Edge walk alone is rarely enough for fills on stretchy or pile fabrics. Combine it with a second underlay layer for better results.
Zigzag (Double Zigzag) Underlay
A back-and-forth zigzag pattern that covers the interior of a fill area. It runs perpendicular or diagonal to the top fill direction, creating a mesh foundation.
Use it for
- —Medium-weight knits and jerseys
- —Polo shirts and structured wovens
- —Most standard left-chest logo placements
Zigzag underlay is the workhorse of embroidery — if you're not sure which underlay to use, start here for fills on standard garments.
Grid (Lattice) Underlay
Two passes of zigzag or running stitches crossing at 90° (or 45° and 135°), forming a grid pattern. It creates the most stable foundation and the most compression.
Use it for
- —Heavy fleece and French terry hoodies
- —Towels and terry cloth
- —Velvet and velveteen
- —Any high-pile fabric where stitches tend to sink
Underlay for Satin Columns
Satin columns (used for lettering, outlines, and borders) use different underlay than fill areas. The standard approach is a single center run of running stitches down the middle of the column, which stabilizes the column without adding visible bulk.
For wide satin columns (over 6mm), add edge walk underlay on both sides of the column in addition to the center run. Wide columns without edge walk tend to roll and gap in the center.
Common Underlay Mistakes
- —No underlay at all — top stitches sink into pile fabrics
- —Using grid underlay on thin wovens — adds unnecessary weight
- —Underlay that runs in the same direction as top stitches — provides no compression benefit
- —Skipping underlay on caps — curved framing needs the extra stabilization