Frobnitz
Origin
Coined circa 1958 by David R. Sawyer of the MIT Tech Model Railroad Club (TMRC) as a fanciful name for model railroad parts, perhaps originally as a proper noun.
Jargon File|frobnicate, quoting Peter Samson: “Under the TMRC railroad layout were many storage boxes, managed (in 1958) by David R. Sawyer. Several had fanciful designations written on them, such as ‘Frobnitz Coil Oil’. Perhaps DRS intended Frobnitz to be a proper name, but the name was quickly taken for the thingâ€.
More general use presumably dates from the 1960s, as it is not found in the TMRC dictionaries of 1959 or 1960.
Peter Samson, AN ABRIDGED DICTIONARY of the TMRC LANGUAGE June 1959 (with 2005 commentary),
AN ABRIDGED DICTIONARY of the TMRC LANGUAGE late summer/early fall 1960 (with 2005 commentary)