DIY From the Archives: Make Your Own Magnetic Postage Scale

Postage prices just went up again (groan). Save yourself some change by using this DIY device to find out exactly how many stamps to slap on to that overstuffed envelope

By Joel Barnard Posted 06.18.2009 at 2:48 pm 1 Comment

DIY Postage Scale Joel Barnard

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You’ve successfully tested the limits of how much can fit into a #10 envelope without bursting its seams, but now you’re questioning how much postage you need. Sure you could just slap a few of the new 44-cent stamps onto whatever you're sending and be done with it, but that’s good money you’re throwing away.

Instead, spend just a few bucks now to build a simple magnetic postage scale, newly updated from an original article in the February 1971 issue of Popular Science.

This handy little device works by balancing the unknown weight (your obese letter) against a calibrated opposing force developed by five or six small ring magnets poled to repel each other.

Go ahead and make your own!

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1 Comment

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katachresis

06/18/09 at 5:17 pm

It's important to remember that pennies pre 1982 were 3.1 grams, but pennies after 1982 are 2.5 grams. You should adjust for calibration accordingly. Also 28.34 grams is an ounce (avoirdupois) these days.