Answered By: Beth Hylen
Last Updated: Sep 30, 2016     Views: 57

I am not sure about the terminology you are using, so I am sending several possibilities. If none of these meet your needs, please contact me again with a little more information about how you will use the techniques.

Bill Gudenrath uses the term"cracking off" in this video: 

the technique is similar to videos I found online for "hot popping."

I added scans of "hot wire cutting" of Pyrex and soft glasses as well as "Cutting Bottles with a Flame" from Wheeler's Scientific Glassblowing [NY: Interscience Publishers, 1958], pp. 58-62.

When I toured the Libbey factory last year, they were using a mechanized version of this technique to open their mold blown tumblers and wine glasses. Is this what you are looking for?

I had better luck with "fire polishing" glassware.

I'm sending a scan from Giegerich and Trier's book, Glass Machines: Construction and Operation of Machines for the Forming of Hot Glass. [NY: Springer-Verlag, 1969]. The Owens-Schwartzkopff Type OS machine is a "suction blow" machine that includes fire polishing bottles, pp. 230-231.

Pincus' book, Secondary Manufacturing in the Glass Industry, includes several articles about fire polishing and I am sending scans of those pages.

Pincus, Alexis George. Secondary manufacturing in the glass industry / compiled by Alexis G. Pincus and S. H. Chang. New York, Books for Industry, 1978. x, 314 p. A collection of articles published in The Glass Industry magazine, 1920-1977. Bibliography : p. 296-311. (Processing in the glass industry) Location: Stacks Call Number: TP863 .P64

Please let me know the context and I'll be happy to look further for information.

Best wishes,