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Many
thousands of years ago, a man picked up a pebble from the bed of a
stream. He compared it with the ones on the river bank, saw how much
smoother and rounder it was, and realised that this must have been
caused by the water flowing over it.
Another man, also long ago but in a different place, turned a
rough-cut stone axe over and over in his hands. He realised that the
times were changing, and that he could obtain a much finer finish by
using sand to abrade the stone.
In
more recent history, Roman soldiers on their way to battle placed
their swords, shields, helmets and breastplates into jute sacks full
of sand and pieces of leather. They loaded these onto carts, so that
they would be polished by the movement as they went along, and the
resulting brilliance struck fear into the hearts of their enemies.
Today, at the turning point of the third millennium, we face a whole
new set of needs and problems in an increasingly competitive global
market. We are entering a new era in mass finishing techniques, with
high-technology vibratory media, new materials being used to make
flexible abrasive tools, and new designs. As a result, the finishing
process is becoming faster and more effective, with fewer financial or
environmental drawbacks.
We
have come a long way since our ancestors discovered abrasives all
those tens of thousands of years ago, and we have made rapid progress
even in the last few years. Even just a few years ago, we could not
have imagined how advanced technology could be used to achieve surface
finishes of the quality we see today.
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