Where does this come from, and can I check it?

A flat spiral spring inside the case stores energy as the blade is pulled out. The figure is taken from National Institute of Standards and Technology, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a everyday life fact?

Yes. It sits on the Everyday Life shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

A retractable tape rewinds with a coiled spring

A flat spiral spring inside the case stores energy as the blade is pulled out The spring is a long strip of tempered steel wound into a tight spiral, and pulling the blade out winds it further. Releasing the blade lets the spring unwind and drag the tape back, while a brake shoe on the button holds it at any length. The hook is riveted loosely so it can slide by its own thickness, which keeps inside and outside readings honest. It sits in Mondo's everyday life collection, one of 200 facts that each trace back to the reference below.

Where this comes from

National Institute of Standards and Technology

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Technology trivia General Knowledge trivia

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A binder clip is one folded strip of steelThe looped handles are the spring, squeezed to open the jaws A spring clothes peg pivots on a coiled springTwo shaped halves meet at a coil that pushes the gripping ends together A try square keeps its blade at ninety degreesThe raised handle registers against the edge and holds the blade square Tape measure hooks slide to allow inside measurementsThe loose rivets let the hook move by its own thickness on purpose A spirit level reads tilt from a trapped bubbleThe liquid surface stays level, so the bubble parks between the marks Sandpaper grit numbers count mesh openingsA coarser paper has a low number because fewer strands cross each inch

Tags: tools, measurement, springs

A retractable tape rewinds with a coiled spring: the short answers

Where does this come from, and can I check it?: A flat spiral spring inside the case stores energy as the blade is pulled out. The figure is taken from National Institute of Standards and Technology, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a everyday life fact?: Yes. It sits on the Everyday Life shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.