OWA
BRIEFWAAGE
OWA
LETTER SCALE

maker: Oschatzter Waagenfabrik Otto Bielig, Oschatz, Germany
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letter scale, maker Otto Bielig
the OWA weight lifting letter scale - Otto Bielig Hubgewichtswaage
 

This hefty letter scale was made by Oschatzter Waagenfabrik Otto Bielig, from Oschatz, Germany. This scale factory was founded in 1922. This scale was intended for use in larger companies and at post offices. It is a weight lifting letter scale in which one arm of the mechanism picks up more and more counterweights when a heavier load is placed on the letter platform until a balance is found. The scale has seven weight limits that it can exceed, namely 20, 50, 100, 250, 500, 1000, and 2000 grams. With a load above 2000 grams, the arm will hit a stop. With an over or underweight of a few tenths of a gram, the pointer moves to the nearest higher or lower weight zone. To prevent a long lasting oscillation of the scale mechanism, an oil damper has been applied to the moving scale arm. This OWA letter scale can be read on the two long sides. The postal rates are clearly arranged. For rate adjustments, a new rate card must be affixed to both sides of the scale. This letter scale model is best known with the brand name Bizerba. I don't know what the relationship is between Bizerba and the Oschatzer Waagenfabrik Otto Bielig. The dimensions: base plate 33 x 18 cm, scale house 28.5 x 16.5 x 22 cm high, letter plate 11 x 11 cm at 28.5 cm height. This letter scale is heavy, namely 10.3 kilograms! The scale has three adjustable feet and a vial helps to level the scale.

other side of the scale
other side of the letter scale
 

In Germany, the first letter scale of this type was approved for calibration at the beginning of February 1933. My OWA copy dates from December 1941. In 1946 the Oschatzer Waag Fabrik Otto Bielig was expropriated by the East German state.
The idea to achieve an increasing counterweight with multiple weight rolls, or rolling pins, was already applied in England in a letter scale on August 12, 1840 by Robert Willis and patented in the English patent no.8384. Rein Kok wrote in Meten & Wegen No.118 June 2002, pp.2808-2810 about the Bizerba Hubgewichtswaage in an article with the title: Een oude brievenweger in moderne uitvoering. (This is Dutch, translated: An Old Letter Scale in a modern design).
Below are some images of this robust letter scale.

detail 1
one of the figures from Dingler's Polytechnisches Journal
Band 79, 1841, pages 98-102 and Tab. II
detail 2
the images from the OWA brochure [source: Stadt- & Waagenmuseum, Oschatz]
 
detail 3
figure from Mechanics' Magazine No.885, July 25, 1840
pages 148-149
detail 4
the lift arm lifts all seven rollers, pointer beyond 2000g
 
detail 5
these yellow/white striped postal rates from 1 July 1974 were
later applied to this letter scale. The original postal rates
from 1941 were in red/white striped and in an old font
 
detail 6
the oil damper is only accessible after disassembly
of the scale house and the nearby tariff plate
 
loaded to the max
animation:
from no load to a load above 1000g
[move the pointer over the photo]
 
the parts of the oil damper
the three parts of the disassembled oil damper, the inner
diameter of the damper housing is smaller at the lower half
 
 
the damper in motion
animation:
the movement of the oil damper
[move the pointer over the photo]
 
twee wegerstanden
animation: charged with 20+ grams
[move the pointer over the photo]
 
twee wegerstanden
animation: charged to 1000-2000 grams
[move the pointer over the photo]
 
twee wegerstanden
animation: from zero to 1000-2000 grams
[move the pointer over the photo]
 
detail 7
the letter scale without the scale housing, without
the postal rates plates and without the oil damper
 
detail 8
the seven weight rolls seen from above
 
detail 9
the seven postal weight classes in the old typeface
 
detail 10
the side with calibration lead area, spirit level,
and brand plate
 
detail 11
the lead with stamped banderole calibration mark
 
 
detail 12
the spirit level indicates level
 
 
detail 13
this side has two adjustable feet
 
detail 14
Otto Bielig's brand plate from December 1941
 
detail 15
the adjustable feet have a securing lock nut
 
detail 16
the lead seal with calibration office mark
 
detail 17
on both sides the seal is like this
 
detail 18
the seal on the other side of the scale
 
detail 19
cup with fine adjustment lead balls
 
detail 20
the cup in the right place
 
detail 21
the lead balls are in the cup
 
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« collection part 22 «© copyright André Solversion: November 30, 2021