gaffer "glass blower" -- Origin of term?

[Cohen, Gerald Leonard]

One of my students asked me about the origin of the term "gaffer" (glass blower),

and I checked OED but couldn't find it there with that meaning.  Did I somehow overlook something obvious? Would anyone know its etymology?



Here is an Internet example of its use:



http://chemistry.boisestate.edu/people/richardbanks/glassblowing/glassblowing_history.htm



Glass blowing of vases and art objects is still done in basically the same way as it was originally done. Glass blowers (gaffers) use a hollow iron pipe about four feet long. The gaffer dips the pipe in the melt and rolls a small amount of molten glass (gather) on the end. The gaffer then rolls the gather against a paddle or metal plate to give it an initial shape (marvering). The gaffer then blows into the pipe creating a bubble (parison).

The gaffer controls the shape and thickness by reheating the parison at the furnace and shaping and blowing to create the final form. Wooden paddles with holes and wet newspapers held in the hand are all used to shape the glass. Shears can be used to cut the softened glass. Additional gathers can be applied and shaped into stems, handles, and other decorative artwork. The hot piece of glassware can be dipped into molten glass of a contrasting color (flashed). The gather is attached opposite the blowpipe to a solid iron rod called a pontil. After the blowpipe is broken free, the gaffer can then shape and fire polish the open end. After the pontil is broken off, the rough spot that is left (pontil mark) is removed by grinding and polishing.



------ Any help would be much appreciated.



Gerald Cohen

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