The toe: one seam, three ways to close it, and the money between them

One seam

A plain sock has exactly one sewn seam, and it is across the toe. Everything else is knitted: the welt, the rib, the heel pocket, the reinforced sole, the cuff. Course 4.2 teaches stitch and seam classes on a garment with forty seams in it. Here there is one, and that turns most of a merchandiser's habits upside down.

Three things follow at once.

The toe carries the whole sewing risk. A defect list for a woven shirt is mostly seam faults. A defect list for a sock is mostly knitting faults: dropped stitches, needle lines, oil marks, shade bars. There is one sewing entry on it. Your sewing quality plan for this order is a plan for one operation.

The toe carries the whole comfort complaint. It sits across the ends of the toes, inside a shoe, under load, all day. It is the most complained-about feature of any sock. A bulky one is the reason a customer does not buy the second pack.

The toe is the last thing done, and the easiest thing to under-resource. Knitting is 6.48 days on machines nobody can add to. Toe closing is people, and people can be added. That is exactly why it gets planned last and goes wrong.

Three ways to close it

The word seamless is used commercially for all three routes that leave no ridge. Know that before you repeat it to a customer. On a specification, write what you mean: linked, closed, or knitted closed. Only the third has no seam.

The money

Tanyeri's loaded operator rate is USD 3.20 an hour. Loaded means the wage plus the social charges the mill pays on top of it. Hand linking at 95 socks an hour is USD 0.0337 a sock. Twenty-four socks, which is one dozen pairs, is USD 0.81.

The automatic closer is a station. The operator costs USD 3.20, and machine depreciation, power and blades add USD 0.62 an hour. That is USD 3.82 an hour for 620 socks. One dozen pairs is USD 0.15.

The gap is USD 0.66 a dozen pairs, or USD 4,756 on this order. That is 5.8% of the order value, and more than half the quoted margin, on one operation that takes a few seconds.

Which is why the break-even is short. A closer costs about USD 30,000. At USD 0.66 saved a dozen pairs it pays for itself in 45,417 dozen pairs, and Tanyeri passes that in well under a year. Any mill doing volume socks owns closers. A mill quoting you hand-linked toes at a volume price either has a customer who insists on it, or has not costed it.

The third route, and why it is not obviously best

Closing on the knitting machine removes the operation completely. It also costs money in two places that never appear on a toe-closing line.

An auto-toe machine costs about USD 38,000 instead of USD 22,000. That raises the machine-minute rate from USD 0.0155 to USD 0.0206. And the cycle goes from 2.75 minutes a sock to about 2.93.

So the seamless route costs USD 0.28 a dozen pairs more, and it takes 6.7% longer per cycle. On a floor already limited by bank C in lesson 1, that is capacity you do not have.

It is still the right answer for some products. A running sock, a diabetic sock, a child's sock, anything sold on comfort: there the ridge is the product's whole argument, and USD 0.28 a dozen pairs is nothing against a return. For a five-pack of cushioned everyday crew socks at USD 11.40 a dozen pairs, it is not.

What to write in the tech pack

Three lines, and most sock tech packs carry none of them.

1. The route, named the way this lesson names it, not as "seamless".
2. The stitch, if a closer is used. A chain stitch will run back from a single broken loop, so the seam opens along its whole length instead of at one point. That is acceptable on a bag closure and unacceptable across a toe. It is the reason a toe seam is specified rather than left to the closer's default setting.
3. The acceptance, in words a hand can check: a ridge no thicker than the sock's own fabric, and no thread ends inside.

Act as a hosiery costing manager. Build me a cost sheet for one sock style per DOZEN PAIRS, and name the denominator underneath every line, because the lines in a sock cost sheet are counted in at least five different units and that is where the errors live. Style facts: [STYLE], [QTY] dozen pairs, price [AMOUNT] a dozen pairs, terms [TERMS], pack format [HOW MANY PAIRS TO A PACK]. Size ranges, their share of the order, and the finished weight in grams a pair for EACH size: [LIST THEM]. Yarns bought, with grams a dozen pairs and price a kilogramme: [LIST EACH, AND SAY WHICH ONE IS THE COVERED ELASTANE AND WHAT ITS CORE AND COVERING ARE]. Over-issue above the in-sock weight: [PERCENT]. Dyeing: [PRICE A KILOGRAMME], machine load [KG], and the split between chemistry that scales with weight and machine cost that does not, if known. Knitting: cycle minutes a sock and the machine-minute rate. Toe closing: the route and its rate. Boarding, pairing, packing and packaging: rates and the unit each is quoted in. Seconds rate and the salvage value of a second. Freight and overhead. Do the following. First, build the cost per dozen pairs line by line with the denominator written beside each line, and flag any line I have given you in the wrong unit. Second, reconcile the yarn bill against the label composition, showing how much of the covered elastane yarn is core and how much is covering, and what percentage of the finished sock each declared fibre is. Third, recalculate the yarn and dyeing lines at the ORDER'S BLENDED WEIGHT rather than at the middle size, and tell me in money what the size mix costs against the size the quote was built on. Fourth, express seconds as a cost per SHIPPABLE dozen pairs, net of salvage, not as a percentage. Fifth, carry it to a margin a dozen pairs and a margin on the order. Sixth, tell me what a defective sock costs at each unit: opened and remade at the mill, and sorted at the customer's warehouse. Name every assumption in a list at the end, and do not give me a range where a number is possible.