Pittsburgh - New Kensington - Butler - Leechburg - Natrona Heights - Kittanning - Freeport
Tarentum - Lower Burrell - Vandergrift - Ford City - Hyde Park - Fox Chapel - Brackenridge

Your Guide to the
Alle-Kiski Valley
and the Greater
Pittsburgh Area

October 14, 2019


Go Outside    



Back Issues    

History - Industry - PPG Tarentum

Revolving Iron Disks Grinding Surface of Plate Glass

Here we see a plate of glass after it has been thoroughly set and is nearly ready for sale. The machines now used for the grinding save a great deal of time. The improvement is chiefly in the March transfer polishing table, which combines the advantages of reducing the temperature of the glass while grinding, by circulating water below it, thus permitting a much higher speed in the grinders, with a device for polishing the under side of the plate, without the frequently disastrous operation of removing it from its plaster bed and turning it over. This transfer table is also movable from grinder to polisher, effecting in this way a considerable saving of time, while ensuring the greatest security in handling.

There used to be many restrictions upon the output of the glass-workers by the Glass-Workers' Union but immigrants, willing to work on an unlimited plan, forced themselves into the trade, and this compelled the Union, for self-protection, to remove the restrictions on its members. The increased production because of the removal of the union limitations amounted, in one case, to 100 per cent, and the increase of earnings to about fifteen per cent. A discriminating entrance fee, so effective in other instances, is employed by the flint-glass workers to protect themselves against an influx of cheap foreign workmen.

Next - Workmen Finishing Plate Glass Windows

Previous - Casting and Rolling Sheets of Plate Glass

Return - PPG Tarentum

Copyright 1999-2014 by Darren McPhilimy, All Rights Reserved.