Mechanical Scale - Mail

This simple mechanical scale indicates if your letter needs 1, 2, or more stamps for first-class mailing by the US Post Office.  A one-ounce letter requires 1 stamp.  A two-ounce letter requires a second stamp.  Over two ounces costs more.

You will need to add a clip to the scale to attach the envelope and a counterbalance weight in the hole.  I used a ¼” x 1” bolt and nut.   

You will need to make 1 and 2-oz envelopes to calibrate your scale.  

The pointer and ring a sufficiently flexible to be put together.