Boundary behaviour and finishing in intarsia

Machine types that can knit it

• Single bed, punch card
• Single bed, electronic
• Single bed, no patterning
• Single bed (punch card) + ribber
• Single bed (electronic) + ribber
• Double bed with pushers (Passap type)

Steps

1. Default: cross at every boundary on every row.
2. Steep diagonals (≤1 step per row): cross normally.
3. Shallow diagonals (>2 stitches per row): catch the travelling yarn halfway, or redraw the chart steeper.
4. Finish each area by crossing once more before cutting.
5. Weave the ends diagonally on the purl side, splitting the purl bumps.

The full card

What it looks like

Vertical boundary: a straight column join, where the edge stitch can look larger. Diagonal: staircase steps of 1+ stitch per row. Horizontal: a clean colour line with no crossing.

How it behaves

Flat. Tightly pulled diagonals pucker.

How it works

Vertical edges need a cross every row, otherwise the two areas separate into a slit. On diagonals, the yarn moving into the new area travels a few stitches as a short float on the back. Steps leaning one way partly interlock by themselves; steps leaning the other way still need a cross. Crossing anyway is the safe default (hand-knitting source; the machine analogue is [inference]). A horizontal boundary is a plain colour change: break the old yarn and join a new one, with tails to weave in.

Machines

All intarsia methods.

Parameters

max horizontal step per row before a float is needed ≈ 2–3 stitches (standard gauge) [inference]; weave tails 5–8 stitches diagonally on the purl side; pre-tug the new yarn at vertical joins to tighten the edge stitch.

Steps

1) Default: cross at every boundary on every row. 2) Steep diagonals (≤1 step per row): cross normally. 3) Shallow diagonals (>2 stitches per row): catch the travelling yarn halfway, or redraw the chart steeper. 4) Finish each area by crossing once more before cutting. 5) Weave the ends diagonally on the purl side, splitting the purl bumps.

Charting

Default crossing is implicit. Draw slits (no cross) as a double vertical line ‖. Mark steps wider than 2 with a small "f" (float) at the boundary.

Limits and common problems

1-stitch-wide areas or lines → use Swiss darning/duplicate stitch afterwards instead. Too loose a tension shows the joins.

Related techniques

• Hand-laid intarsia, single bed
• Intarsia carriage or built-in intarsia setting
• Intarsia by holding, one carriage pass per colour
• Partial-knit pseudo-intarsia
• Diamond / lozenge colour block