PRESTO letter scale
maker: Metal Specialty Manufacturing Co. Chicago, USA
Presto letter scale
| The Presto is a spring balance. This spring is a leaf spring riveted to the bottom of the housing of the scale. The indicator strip and a V-shaped transverse strip are connected to the free end of the spring. Letters rest on this transverse strip. The housing is made of two parts. The bottom and front are one part. The sides and the sloping top form the second part. Both parts are connected by protrusions folded into a couple of slots. The applied steel plate is massive (± 1.3 mm). It is a remarkable heavy letter scale, which, as a paper-weight, functions very well. This letter scale is a strange combination of round forms with ugly pointed forms. The paper chart is glued at the front.
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indicator and V-shaped strip
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red presto | 
blue presto |
The range is limited to 6 oz. The rates of First class, Airmail en Third class mail are given. The stated First class rate was valid from 1932 till 1958. The stated rate for Airmail was only valid from 1946 till 1949. Therefore, this letter scale dates from 1946-1949. At the bottom there is this text: LETTER SCALE MFD, BY METAL SPEC,MFG.CO. CHICAGO,24,ILL. PAT. APPL'D FOR. Indeed, a patent was granted: US patent 2,458,129. It was granted on January 4, 1949 to Walter R. Amstutz of the firm mentioned earlier. The application was already made January 13, 1947. Besides the green chart, also red and blue charts were made. Below some more photos of this letter scale.
round and pointed forms
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top view
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letter placed in groove
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figure 1 of patent 2,458,129
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made of thick steel plates
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cross-section
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side-view |
green chart
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model name |