Americanmachinist 2963 Retro0102png00000002061
Americanmachinist 2963 Retro0102png00000002061
Americanmachinist 2963 Retro0102png00000002061
Americanmachinist 2963 Retro0102png00000002061
Americanmachinist 2963 Retro0102png00000002061

Working on the crane gang

Oct. 1, 2004
A letter to the editors, entitled "A Workman's Spite," printed in the October 6, 1904, issue, described the writer's recent experience with an old lifting crane that was the source of long-standing conflict: The machinist who erected the crane seriously d
A letter to the editors, entitled "A Workman's Spite," printed in the October 6, 1904, issue, described the writer's recent experience with an old lifting crane that was the source of long-standing conflict: The machinist who erected the crane seriously disagreed with the crane's design and spared no words in making his dislike known. When the crane had to be moved to another area, the repair gang went to work disassembling it, only to find this an impossible task.

When the casting on the crane was finally broken, writes the author, "The secret of over sixty years was revealed: Every joint, all the spaces between the castings, and even the bolts, had been covered or filled with a mixture of sal-ammoniac and iron borings, which form the well-known 'rust joint,' and it had rusted up so solidly that the crane was, to all practical purposes, a single solid casting. It had to be taken apart by the aid of dynamite...."

The author implied that the disgruntled machinist may have intentionally caused the problem. In response, the editors reminded him that "the rust joint was quite commonly used in the days when the crane was built... and we prefer to assume it was used entirely with good intent."

Oldest and still the best?

"Water long has been considered the best coolant for most grinding operations," wrote editors in the October 11, 1954, issue, "but it has the disadvantage that unless treated with an anti-rust additive, it causes rapid corrosion of both machines and work." Editors then described their rediscovery of an old-fashioned substance — "sal soda," or sodium carbonate — in use in every grinder of one large machine shop. At one time used as a coolant additive, this substance had long been abandoned for more modern soluble-oil bases. However, the general foreman of the shop swore by the use of sal soda, saying that he had "tried every available base for making grinding coolants, but that none matches sal soda in terms of fine surface finishes, reduced wheel loading and wear, and low over-all costs."