FRONTIER GOODS LTD Taking readings

Taking the readings

Fields 04, 05 and 06 are the only figures on the sheet produced by an instrument rather than by a transcription. This page is the method: where the item sits, how many times it is read, which reading is kept and what is written down when a reading will not settle.

A specimen bench: the item measured across its widest axis, the three readings written down, and the same item on the scale with its net and gross masses Left, an item stands on a flat surface with a rule set beneath its widest axis. Centre, three readings of that axis are written out and the largest is ringed as the one kept. Right, the item sits on a scale platform under a readout giving a net and a gross mass in grams. WIDEST POINT OF THE AXIS SPECIMEN READINGS — ONE AXIS READ 1 141 mm READ 2 142 mm READ 3 141 mm LARGEST KEPT, ROUNDED UP NET 1240 g GROSS 1410 g
A specimen bench, read left to right. The item stands free on a flat surface; the rule is set under the widest point of the axis, not the nominal one. The three readings are written down in full and the largest is the one that goes on the sheet. The same item then goes on the scale for a net and a gross mass. The figures drawn here are a worked example and measure nothing in particular.

The bench

Readings are taken with the item at rest on a flat surface, under even light, with the item free-standing rather than held. Nothing is read while it is in a hand, a bag or a part-made pack: the weight of a hand shows on a scale, and an item under tension measures smaller than it is. The instrument used is named on the slip — rule, caliper or scale — and so is the surface, because a reading taken on a soft surface is a different reading.

Three readings to an axis

  1. 1

    Find the widest point of the axis

    Not the nominal point and not the middle. A moulding seam, a hinge or a foot is part of the item and is included.

  2. 2

    Read it three times, setting the instrument down between readings

    Reading the same contact three times proves nothing; the point is to re-approach the item.

  3. 3

    Keep the largest of the three

    Not the mean. The largest reading is the one the packed form has to accommodate.

  4. 4

    Round up to the whole millimetre

    Rounding down would understate an axis, and an understated axis puts the item into a packed form that does not close.

  5. 5

    Write all three readings on the slip, not only the kept one

    A single surviving figure cannot be checked later; three can.

Mass

The scale is zeroed immediately before each item, not once at the start of a session. Two figures are taken: net, the item alone, and gross, the item in the form it would be despatched in. Both or neither — a net mass with no gross beside it invites someone later to treat it as the gross. Masses are written in whole grams, rounded up, and the scale’s own graduation is written on the slip so that a figure is never read as more precise than the instrument that produced it.

A reading that will not settle is written as the range it moved through, both ends of it, and the number of seconds it was watched — never averaged into a single tidy figure. Some items do not give one answer: a soft pack, a loose fill, anything that creeps on the platen. A range is useful to whoever reads the sheet next, and an average conceals exactly the thing they would need to know.

Packed volume

Field 06 is computed, not read: the three packed dimensions multiplied together, converted to cubic centimetres and rounded up. It is the only derived field on the sheet and the only one carrying two signatures, because it inherits every error in the three figures behind it. It cannot be filled from the item’s own dimensions, which is why it stands blank until a packed form has actually been made up.

The reading slip

Each session produces a slip carrying the line reference, the date, the instrument, the surface, all three readings for each axis, the kept figure, the scale graduation and the signature of whoever took them. The slip is kept separately from the sheet, because the two answer different questions: the sheet says what the figure is, and the slip says how it was arrived at and whether it can be reproduced. A retake is a fresh slip, never an edit to the old one, and the two slips are read side by side. The sheet’s amendment rule then governs what changes on the record itself.