Cloth or recipe: buying the same look twice

The situation

2 April, Ulvan's costing office. Two quotations for the same construction, both 11.5 oz comfort-stretch, both delivered to Corlu:

• Terkos, ring-spun warp, rope-dyed: USD 4.05 a metre.
• A second mill, open-end warp, slasher-dyed: USD 3.28 a metre.

Ring-spun yarn is twisted the slow way and has an uneven surface. Open-end yarn is made faster and comes out flat and regular. Rope dyeing runs the warp through indigo as thick ropes, so the dye stays near the surface and leaves a white core. Slasher dyeing runs it as a flat sheet, and the colour sits more evenly.

Seventy-seven cents a metre, on an order of nineteen thousand metres. In most categories that is a straightforward saving and the conversation lasts four minutes.

What makes denim different

In almost every other category the fabric decision and the finishing decision are independent. You cannot buy a better hand on a knitted top by dyeing it longer. You cannot make a poplin shirt look like a better poplin in the finishing line. The two lines of the cost sheet do not talk to each other.

On denim they are substitutes for the same visual outcome. The look Tarnwick sealed on 6 May is a contrast — pale where the garment stands proud, dark where it does not — and there are two ways to buy it. You can buy it at the mill, in a ring-spun yarn with an irregular surface and deep rope dyeing that leaves a white core to expose. Or you can buy it at the laundry, by abrading a flat open-end yarn long enough and hard enough to force the same contrast out of less. Course 2.4 explains why the yarn behaves that way. What matters here is that the two are exchangeable, so neither line of the cost sheet can be quoted alone.

That is the category rule. A denim quotation that prices cloth without naming the recipe it assumes, or prices a wash without naming the cloth it was trialled on, has not priced anything.

The two routes, on one jean

Sarband trialled the cheaper cloth and reported what it would take to reach the sealed standard. The short recipe does not get there. The recipe that does adds a stone step, a light bleach and the neutralisation that follows it.

Desizing washes out the starch put on the warp to survive weaving. Two things in that table are worth stopping on before the money.

The consumption is not the same. The harsher recipe shrinks the cloth more, the pattern is cut bigger to compensate, and the marker grows with it. So the cheaper cloth is also used in greater quantity — 1.531 m against 1.482 m. The saving of USD 0.77 a metre is worth USD 0.98 a pair, not USD 1.14.

The minutes are the laundry's calendar. At 240 pairs a load, this order is 53 loads. Route 1 holds a machine for 48.58 hours. Route 2 holds it for 119.25. That is 70.67 machine-hours you have to buy from a company whose order book you do not control, and it is invisible on a cost sheet.

Carried to a margin

Everything except cloth and wash is the same on both routes: trims USD 1.72, CMT USD 3.05, finishing and packing USD 0.38, freight to the laundry and back USD 0.07, factory overhead and margin USD 2.20. That is USD 7.42.

The cheaper cloth costs USD 0.65 a pair, or USD 8,190.00 on the order. The saving was real and it was never available, because it was a saving on one line of a pair of lines that move together.

The reject line is the one people leave out, and on denim it is never small. A pair scrapped at the laundry has already absorbed its cloth, its trims, its cutting, its sewing and its wash. It is the most expensive unit of loss in the order. Route 2 runs a bleach step. Bleach is fast, cheap and unforgiving, and 2.4 percent against 0.9 percent is what that costs.

And the route that costs more is also the riskier one

Two more things follow the harsher recipe, and neither shows on the cost sheet.

Strength. The bleach takes warp tensile strength from 412 N unwashed to 296 N, against Tarnwick's floor of 280 N. That is 16 newtons of headroom on a test whose result moves with the neutralisation, the storage temperature and the laboratory's grip method. How to read that floor properly is course 3.6's third lesson. The point here is that route 2 spends the headroom route 1 leaves intact.

Time. Seventy hours of extra machine time in a shared laundry is not seventy hours of delay. But it is seventy hours you have to find in somebody else's calendar, and lesson 5 shows what happens when you cannot.

The booking nobody can make correctly

Now the second half. This one is specific to product that is finished after it is made.

Ulvan booked cloth on 2 April: 12,600 pairs at a trial consumption of 1.462 m, plus four percent for ends and cutting loss, rounded up to the mill's put-up — 19,200 m. Correct practice, done on the right day, because a rope-dyed lot has a lead time and the cut plan needed it.

The wash standard was sealed on 6 May. The corrected pattern arrived on 8 July. It consumes 1.482 m, so the order needs 19,420.1 m.

The booking is 220.1 m short. It was short from the moment it was made, because it was made against a pattern that did not exist yet.

The right answer was available in April and costs a quarter of the wrong one. On a garment-washed product you are booking cloth against a shrinkage figure that is not approved yet. So book against the harshest recipe still under discussion, not the trial one, and put the over-book on the cost sheet as a line with a number. Then it is a decision somebody made, priced at USD 1,620.00, instead of a shortfall somebody discovers.