Postage Scale

Save a trip to post office and weigh your envelopes and Christmas cards at home.

This design has the 1 & 2 ounce weights engraved. However, I would suggest that you make up a test articles to verify the accuracy.  

The beauty of this design is that you can add/subtact a nut or washer to calibrate the reading against a known 1 and 2 oz weight.

The basic USPS first class mail stamp is for  a 1 ounce envelope. 

For the first time since 1959, when I took statics as an ME freshman student, I used a statics calculation to determine the theoretical weight needed (4 oz) on the pendulum to provide a 45 degree  indication at 1 ounce on the scale.  I was surprised that the calculation was pretty close.  

A ¼-20 x 1” bolt,  nut and lock washer provided the 4 oz. 

There is a ¼-20 thread in the pendulum. 

One STL provides the three printed parts.  A second STL is provided if you want different colored pointer and ring.

 Pease verify / validate the scale on your print against known 1 & 2 oz weights.  I don’t  want to get yelled at for being the cause for returned  mail (insufficient postage) and gross incompetence (even if true).

If a different unit of measure is desired, mark the back appropriately.

I needed to incorporate the calibrated (actual) pointer angle into the design. To measure this angle, I used my other offering in this competition, an angle measuring tool.  Actually having a need for that tool was a surprise.

Store bought: 

   paper clip or binder clip (in photo). 
   ¼“ x 20 bolt, nut, lock washer.