Bunton

A horizontal timber or steel beam fixed across a mine shaft, generally at intervals of 4 to 8 feet, carrying the vertical guides that keep a cage, kibble or skip running true as it is raised and lowered.

Historical usage

Buntons appear throughout British shaft engineering from at least the 18th century onward; the Cornish Mining World Heritage glossary lists them among the components of 'pitwork' -- the pump rods, rising main and shaft guides fitted within a working shaft -- and notes that later skips ran on shaft guides that were themselves called buntons interchangeably with the beams that carried them.

How it worked

Buntons and the vertical guides they carry together form a 'shaft set': the guides act as rails that a cage or skip's rollers run along, while the buntons brace the shaft lining and hold the guides rigidly in place across the full width of the shaft. Timber buntons were typically around 6 inches square; later shafts increasingly used rolled steel joists instead.

Why it was used

Without guides held firmly in place by buntons, a hoisted conveyance would swing loosely on its rope, risking a collision with the shaft walls, other equipment, or men working nearby -- particularly dangerous in a shaft also carrying pump rods, cables and pipework.

Risks & limitations

A bunton struck by a conveyance that has come off its guides -- through a broken rope, an overwind, or a mechanical failure -- can capsize or wreck it outright: at Kilton Mine in 1873, a sinking kibble struck a bunton and capsized, killing two of the three men riding in it.

Disasters associated with this term

Included only where MineArchive's own research gives a reasonable evidential basis, with the nature of the relationship stated — not every disaster where this term might plausibly apply.

• Kilton Mine Kibble Accident, 1873 (direct cause)
  The disaster's own narrative directly names the bunton the sinking kibble struck, capsizing it and throwing the three men to the bottom of the shaft.

Sources

1. (secondary) A Cornish mining glossary — Cornish Mining World Heritage Site (UNESCO)
2. (secondary) Shaft Guides & Shaft Sets — Sell Lumber Corporation

Record created: 2 September 2026 · Last researched: 2 September 2026