How Etchings Were Made

From a Cambridge Glass Company Brochure

The etching process started with two basic ingredients, an engraved plate and a solution called "etching ground".

The plate was metal and had the background area etched away so that the main design area appeared in raised relief.  Several different size plates were required in each pattern to accommodate the variety of sizes and shapes of the many blanks.

The etching ground solution was prepared in the factory.  It consisted mainly of beeswax, lamp-black, rosin and turpentine.  These ingredients were mixed together and cooked at least overnight before they were used.

The etching ground was applied to the engraved plate with a special steel knife which would deposit the wax into the low areas of a plate and would keep the higher pattern area scraped clean.

A special type of transfer paper, imported from England, was then cut to proper size and applied to the wax covered plate.  A piece of felt would be used to rub the paper and cause it to adhere to the wax.  Keeping the plates slightly warm permitted the wax to be lifted from the plate along with the transfer paper.

The transfer was now ready to be applied to the blank that was to be decorated.   It was covered with wax in all of the areas of background, and the lines that made up the design of the pattern were without the wax cover.  It was then applied in the proper position to the blank and again rubbed gently with felt which caused it to adhere to the glass.  This process was repeated as often as required for the blank that was being prepared.

The blank with the transfers applied was then immersed in a solution of alcohol and water.  This wetting would permit the removal of the paper from the wax, and thus completed the actual pattern transfer operation.

The blank was then sent to a "paint girl" who would cover all of the remaining exposed areas of glass.  Using a small paint brush and working from a heated pot of etching ground, she would complete this operation entirely by hand.

As many a two dozen articles, depending upon their size, would then be stuck to a wax covered board approximately 18 x 24 inches.  This board containing the blanks that were to be etched was then inverted and immersed in a tank of acid.  hydrofluoric acid was used and it was controlled at a constant temperature.

The etching process required a time frame of from three to eight minutes.  This was controlled by the acid's strength and the desired depth of the pattern being etched.

Upon being removed from the acid, the article would be placed in the "scalder".  This was a machine that used a combination of hot water and steam to remove the etching ground from the article.  During this procedure the wax would be carried by the water into a tank built into the base of the machine.  Here the wax would float, enabling the workers to skim it off for reuse.

The article of glass which started out as a plain blank, had now been etched with a pattern and had the wax removed from it.  The final etching process occurred on the sawdust table.  Here the article was dried, cleaned, and polished by a brisk rub-down of sawdust.

If the article was to receive no further decoration it would then be wrapped in tissue and placed in a storage bin.  It would later be sent to the packing room where it would be carefully packed for shipment.