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Rib › Double-bed structures (cardigan, Milano, tubular)

Half and full cardigan (fisherman's rib)

A thick, soft, lofty rib. Half cardigan: the two faces look different; one face shows plump, wide knit columns. Full cardigan: both faces look the same, with very full, rounded rib columns (the classic fisherman's rib)[inference].

Machine types that can knit it

Demo swatch

Drawn for: Double-bed hand flat (V-bed)
Approximate preview worked out from the bed chart, not a photo.
Bed chart
15101520253035→←→←→←→←→←→←→←→←→←→←→←→←→←→←→←→←→←→←Both beds (double jersey)Tuck1 square = 1 stitch × 1 row · read from the bottom · Hand flat (V-bed), 36 needles, half pitch
Needle notation, first steps
1. Row 1: knit 1 rowDouble jersey (all needles)tuck 36carriage →backfront2. Row 2: knit 1 rowDouble jersey (all needles)← carriagebackfront3. Row 3: knit 1 rowDouble jersey (all needles)tuck 36carriage →backfront4. Row 4: knit 1 rowDouble jersey (all needles)← carriagebackfrontShowing needles L12–R12 of 36; repeat across the working area.

Steps

  1. Cast on full needle rib, all needles on both beds, half pitch.
  2. Half cardigan: row 1 front knit, back tuck; row 2 both beds knit. Repeat.
  3. Full cardigan: row 1 front tuck, back knit; row 2 front knit, back tuck. Repeat.
  4. Hang weights evenly; this fabric needs steady take-down [inference].
  5. Measure the gauge on a washed sample: the width changes a lot.

The full card

What it looks like
A thick, soft, lofty rib. Half cardigan: the two faces look different; one face shows plump, wide knit columns. Full cardigan: both faces look the same, with very full, rounded rib columns (the classic fisherman's rib)[inference].
How it behaves
Much wider and thicker than a plain 1×1 rib on the same needles, with less stretch. Full cardigan spreads the most[inference].
How it works
Both beds have all needles in work in full-needle (half-pitch) rib, and tuck stitches are added on one bed or both. Half cardigan: one row knits on the front and tucks on the back; the next row knits on both beds. Full cardigan: one row tucks on the front and knits on the back; the next row knits on the front and tucks on the back. The tucks add extra yarn into every other row, which makes the rib wide and thick.
Machines
Double bed: hand flats such as Dubied (tuck cams), single bed + ribber (ribber tuck levers), industrial V-beds. On a domestic ribber machine the ribber tucks in one direction for half cardigan [unverified]. Full cardigan needs the main bed to tuck on the opposite rows too (tuck setting with every needle selected) [unverified].
Parameters
Pitch: half pitch, all needles in work on both beds. Tension: the tuck rows take up more yarn; most knitters use a tension close to normal rib or slightly tighter [unverified]. Repeat: 2 rows.
Steps
1) Cast on full needle rib, all needles on both beds, half pitch. 2) Half cardigan: row 1 front knit, back tuck; row 2 both beds knit. Repeat. 3) Full cardigan: row 1 front tuck, back knit; row 2 front knit, back tuck. Repeat. 4) Hang weights evenly; this fabric needs steady take-down [inference]. 5) Measure the gauge on a washed sample: the width changes a lot.
Charting
Stoll-style colour key. Half cardigan: a row of "loop front, tuck rear" (pink) alternating with a row of "all needle, double bed" (light blue). Full cardigan: "tuck front, loop rear" (brown) alternating with "loop front, tuck rear" (pink). On a bed chart: tuck cells on the tucking bed, knit cells on the other.
Limits and common problems
Too little take-down → tucks will not knit off and pile up [inference]. The fabric is much wider than rib, so a cardigan-stitch welt flares if it is not planned [inference]. Changing from cardigan to plain rib changes the width.
Combines with
milano-rib (other full-needle structures), vertical-rib, stripes-and-colour-relief (two-colour full cardigan shows a different colour on each face).
Pieces and assembly
Chunky jumpers, scarves, collars, blankets. Factory names in Chinese flat knitting: half cardigan 单元宝, full cardigan 双元宝 [unverified].

Written in our own words from machine manuals, knitting references and swatching. Knit a test swatch before a whole piece.

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