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Staybolt Tap

Staybolt Tap

Usage conditions apply
Staybolt taps were used by boilermakers when installing or repairing the fireboxes of steam locomotives. Taps" are designed to cut threads into drilled holes, so that threaded bolts or threaded machine screws can be screwed in. The long tap was screwed into pre-drilled holes through the boiler's outer steel shell and into the steel firebox within the boiler. The tap cut threads into the hole in the outer boiler shell and also into a corresponding hole in the firebox. The tapped hole permitted a "staybolt" to be inserted and screwed into place; each staybolt held the boiler shell and the firebox firmly together."
This tool is part of a collection of hand tools used in the inspection and repair of steam locomotives in Salisbury, North Carolina from the early- to the mid-20th century, roughly 1900-1955. Light repairs on steam locomotives were usually done in roundhouses at the many small locomotive terminals
Object Name
Staybolt tap
Date made
Physical Description
steel (overall material)
overall: 18 in; x 45.72 cm
ID Number
catalog number
accession number
Credit Line
Gift of National Park Service
See more items in
Work and Industry: Transportation, Railroad
America on the Move
America on The Move
Exhibition Location
National Museum of American History
Data Source
National Museum of American History
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