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Humboldt State University ® Department of Chemistry
From: Fisher Scientific Company. Modern Laboratory Appliances (Catalog 90). Fisher Scientific Company and Eimer and Amend (1942, reprinted 1946) p 48.
In cleaning a balance, remove the hangers and stirrups, and taking hold of the indicator just below the beam, lift the beam slightly and lower the releasing mechanism after which one end and then the other may be lifted from the yoke supporting the stirrups; the beam can then be removed from the bearing at the center. Be careful not to strike the agate edges or to bend the long indicator attached to the beam. Brush the beam with a soft camel-hair brush.
Clean the agate edges and planes with soft tissue paper (cloth may leave lint) moistened with alcohol or gasoline. Do not touch the beam or other lacquered parts with alcohol as it will remove the lacquer.
With a tooth brush, vigorously brush out the grooved supports which carry the agate edges of the stirrups when the balance is arrested. Collected dirt in these grooves causes the stirrups to stick and release unevenly.
Wipe the glass surfaces of the base and case with a chamois; wool or silk cloths will produce "static."
Use the least possible amount of light high-grade oil on metal bearings and sliding contact surfaces of the pan-arrest mechanism and the beam-release mechanism. More oil than is necessary will collect dust and become streaky and is more objectionable than no oil at all. Use no oil on the agate bearings.
Reassemble the balance and be sure that the beam is resting
on its contacts on the releasing mechanism. If the Indicator has
not been bent then the only adjusting which might be required
is that of the balancing screw-weights at the ends of the beam.
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