Patch borders and edge types

Borders

The border is the first part of a patch to fail. It is also the part most buyers never specify, which means the supplier picks it — usually the cheapest one their machine is already set up for. This page sets out the five edge treatments, the shapes each one can and cannot follow, and the practical minimum size below which the border starts eating the artwork.

What the border is actually doing

Two jobs, and they pull in different directions. The first is mechanical: the cut edge of a woven backing cloth will fray, and the border is what stops it. The second is visual: the border is the line that separates the patch from the garment, and its weight changes how the whole design reads at arm’s length.

A border that is doing the first job well can be doing the second badly. A heavy merrowed edge on a small patch seals the cloth perfectly and swallows a third of the visible area. That trade-off is the reason edge type and patch size have to be decided together, not one after the other.

The five treatments

EdgeHow it is madeShapes it followsPractical minimumWhere it fails
MerrowedAn overlock machine wraps a raised cord of thread around the cut edgeCircles, ovals, rounded rectangles, shields with soft cornersAbout 1.5 in / 38 mm acrossAnything with an interior angle or a sharp point — the machine cannot turn that tightly
Hot cutA heated blade cuts the backing and melts the synthetic fibres closed in the same passAny outline, including complex silhouettesAbout 1 in / 25 mm acrossNatural-fibre backings, which char rather than seal
Laser cutA laser follows a vector path and seals as it cuts, with a narrower kerf than a bladeAny outline, including fine points and interior cut-outsAbout 0.75 in / 19 mm acrossThick or multi-layer builds where the beam cannot cut cleanly through
Satin stitchA dense band of flat stitching along the edge, then the surplus is trimmed back to itAny outline, but corners soften as the band turnsAbout 1.25 in / 32 mm acrossHeavy wash cycles, where a trimmed edge outside the stitch line can lift
Rolled edgeThe backing is folded under and stitched down, giving a soft, thick perimeterSimple convex shapes onlyAbout 2 in / 50 mm acrossSmall work and anything with concave curves

Where the minimums come from

None of the figures above is a machine limit. They are the sizes below which the border stops being a frame and starts being the design. A merrowed edge lays down a cord roughly 3 to 4 mm wide, and it does that regardless of how big the patch is. On a 3 in patch that cord is a thin outline. On a 1 in patch it is a quarter of the diameter, and whatever was inside has lost most of its room.

The same arithmetic applies to satin stitch, which is why its minimum sits close to merrowed. Hot cut and laser cut add almost no width at all, which is why they go smaller — and why they are the honest answer for lapel-sized work.

Choosing an edge, in order

  1. Start with the outline. If the shape has an interior angle, a sharp point or a cut-out, merrowed and rolled are already out.
  2. Then the size. Compare the widest dimension against the minimums above. If the shape passes but the size does not, you are choosing between a bigger patch and a cut edge.
  3. Then the backing cloth. Hot cut needs a synthetic backing to seal against. On cotton twill it scorches instead of sealing.
  4. Then the wear. Workwear and anything washed weekly favours merrowed or a stitched edge over a bare cut line.
  5. Then the look. Merrowed reads as traditional and raised. Laser cut reads as flat and modern. Neither is better; they are different signals.

What is published here

The figures on this page are practical minimums drawn from what the treatments physically lay down, not quoted from any one supplier’s price list. Where a supplier tells you a different minimum, they are usually describing their own equipment rather than the method — ask which of the two they mean.