#3138: Dimensional Lumber Tape Measure

XKCD comic, described below.
Transcript

[Header:] Dimensional Lumber Tape Measure

[Paragraph to the left:] Dimensional lumber sizes are tricky. A “2×4” is actually 1½″ by 3½″, and a “1×8” is ¾″ by 7⅛″.

[To its right, a drawing of a rectangular wooden block labelled “2×4”, with notes indicating the length of the height and width being 1½″ and 3½″]

[To the left, two drawings of tape measures seen from the side. One is labeled 12′, and the other is labeled 12′*]

[Paragraph to the right:] If you know someone into carpentry or woodworking, get them our [in italics:]dimensional lumber tape measure.

[Two drawings viewing the extended tapes, with titles, one above the other; The double-riveted 'hook end' fitting is at tape's left-hand 'zero' mark, and they extend off beyond the right edge of the panel featuring digits marking full height "inch" division-lines, with decreasingly partial-height lines indicating half-, quarter-, eighth- and sixteenth-inch sub-divisions from the lower edge, though either measure explicitly indicates the unit being used]

[Title one:] Normal tape measure:

[The measure is divided into inches evenly, the rightmost visible measure being a '9', and slightly further than the next half-inch division being visible at the edge of frame]

[Title two:] Dimensional lumber tape measure:

[The measure is divided unevenly, such that 1st and 2nd marked 'inches' are each equal to a ¾-inch increment on the above drawing, but the 3rd to 7th marks each equate to a 1-inch progression, shifted. The 8th mark is once again ¾-inch after the 7th, and then roughly inch again for the fully visible '9' and '10' numbers and similarly proportional to just beyond the rightmost quarter-inch division visible]

[Slightly bold:]Don’t tell them you got it[Normal weighting:]—just leave it in their toolbox. They’ll appreciate the surprise when all their measurements work out!


(Sourced from explainxkcd.com)

Title text:A person with two watches is never sure what time it is, especially if I got them one of the watches.


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