Ever needed to measure something, but did not have a tape measure handy? Next time, use your iPod headphones!
Just add inch marks to the headphones' cable, and you'll have a 31" long measuring tape that's always with you, with no extra weight or clutter.
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Step 1: Tools and Materials
Soldering iron or other heat source.
Step 2: Make Inch Marks on the Headphones' Cable
The first mark will be on the connector. I used red marker on 10th, 20th, and 30th inch.
Step 3: Heat the Marks
We're not done yet! The marks can rub off and stain your clothes later, and you probably don't want that.
To make the marks last longer, heat them up so that the ink diffuses better into the external surface of the cable sleeve. I used 25W soldering iron, but pretty much any heat source will do.
Hold the cable right on top of the heating element of the hot iron, rotating the cable slowly. Don't let the cable touch the iron! You want the hot air ascending from the iron to make the external surface of the cable's insulation soft, but not melt it. Usually 20 to 30 seconds should be enough, but you might want to experiment a little on an extra bit of cable to determine optimum time.
Step 4: That's It!
Carefully wipe the cable with a piece of cloth to make sure the marks stay permanent and won't run. That's it!