If you eBay or mail things out, you'll eventually need to weigh things to calculate postage. Unless you are a meticulous cook, a chemist, or a drug dealer, you won't have a scale handy at home. This article describes how to build a pretty accurate scale for almost no money.

The linked image shows how to make a scale from a plastic hanger, wooden clothespins, and string. It's a simple balance scale useful for measuring the weight of envelopes, or other "clippable" things.

Click here to see the image in a new window.

Hangers are good for scales because they are cheap and come pre-balanced. For this scale, use a hanger that comes from the store, made of soft plastic that you can drill out with the point of utility knife.

For string, use yarn or any other thick, soft string.

For clothespins, you need wooden ones with springs, because the handle needs to be notched just a little, so the string can be tied on and not slip.

1. Cut the loopy thing off the top of the hanger. You can just cut into the thick parts of the plastic a little, and break it off. Then, find the center of the hanger and drill a hole there with the point of the utility knife (or use a drill or the point of scissors). To find the balancing point, gently hold the hanger between your pinched fingers, so it's free to tip to the right or left side. The center will be near where you think it should be.

2. Drill holes into the left and right arms. Again, they'll be where you think they should be. Try to get out to the ends.

3. Take a wooden clothespin, and use the knife to put a pair of very small notches into the handle. 1mm to 2mm deep is fine. Then, tie a string onto the handle, so it's in the notches. This will hold the thing you're weighing (or the reference weight). Tie the other end of the string to the hole you just made. Do the same for the other arm, with the second clothespin.

4. Tie a piece of string to the balance point. Leave slack on both ends. The top end needs a loop, so you can hang it over a doorknob if necessary. The bottom end should be tied to something heavy, like a bolt or some keys. This bottom part of the string creates a perfect vertical line that's your reference. Use a marker to draw the position of the line when there's no weight on the scale.

5. To use the scale, clip your object to be weighed to one arm, and a "reference weight" to the other arm. A reference weight is a known weight. Here are some known weights:

CD in jewel case and padded mailer = 4+ ounces = 1.35 cents postage
5 cent coin = 5 grams
25 cent coin = 5.670 grams

You can get more "known weights" by taking objects and weighing them at the post office. You can make weights more "clippable" by tying them up in string or putting them in a CD case.

Change the known weights until you get the scale to be balanced. The scale is balanced when the reference line and the marked line match up (obviously).

Tip: You can use Google to convert weights. Type in a search like "80 grams to ounces" and it'll tell you the weight in ounces.

Tip: If you don't cut the loopy thing off, you can continue to use the scale as a hanger. I just cut it off so it won't interfere so much with the top string.

Tip: If you need a more accurate scale, drill the balance point lower. This will move the pivot closer to the ends of the arms. Also, you can move the holes at the ends upwards, and cut the ends off... but if you're doing all this, you might as well just get a stiff stick and use that as the balance. The point of this article is to make a scale cheaply and quickly from materials at home.