The Price per Kilogram You Buy At, and the Cost per Metre You Weave At

How to read this sheet

This sheet does not always favour the better yarn, and that is the point of running it rather than assuming the answer. On the seeded article the efficiency argument wins while the quotes sit within about seven percent of each other and loses beyond that: at a two percent spread the cheap yarn costs seventy-five thousand a year, at four percent forty thousand, and at eight percent the cheap yarn is genuinely cheaper and should be bought. Since quotations for one count usually differ by two to five percent, the quality argument normally holds - but a supplier offering a real ten percent discount is offering something worth taking, and a mill that has learned to always buy the dearer yarn has stopped calculating. Everything rests on break rates measured in your own shed on your own article. A supplier will not quote them, a test certificate will not predict them, and the same yarn behaves differently at a different sett, a different loom speed and a different relative humidity - so a comparison assembled from anything but a trial is a comparison of guesses. Repair minutes matter as much as break counts and are almost never recorded: the figure wanted is the loom stopped, from stop to restart including the walk, not the time the weaver spends mending. Where the shed is sold out the loom hour cost must include the contribution an idle hour forgoes, and leaving it at cash cost alone will understate the whole answer, often by more than the price difference being argued about. Finally, one row of this sheet is one article. A yarn that suits a coarse sett can be the wrong choice on a fine one, and a purchasing decision taken across the range needs the sheet run for each article and the answers weighted by volume.