Part of Historic Environment Scotland

Conservation of Ferrous Metals

Dates: 09/01/19
Days of the week: Tuesday
Total hours: 63
Taught hours: 29
On-site instruction: 13
Off-site instruction: 16


Tackle a range of issues linked to the manufacture and use of ferrous metals – chiefly wrought and cast iron technology – in Scotland’s built environment.

Study the manufacture, use and conservation of ferrous metals in Scotland’s built environment. Wrought and cast iron products are the main focus. But you will also look at the architectural use of corrugated iron sheeting and various minor steel products. Scotland’s leading role in the worldwide architectural castings industry is covered in some depth.

You will gain a practical grasp of the fundamental properties of architectural iron and steel. Combined with conservation best practice, this knowledge will enable you to plan suitable conservation and repair strategies for metalwork – using systematic surveys, accurate assessments and correct specifications and working practices. There is an emphasis on the importance of planned maintenance to slow down corrosion.

You will examine all stages involved in carrying out an ironwork repair project, and get an overview of traditional and current repair and conservation techniques. Central to the specification element of the process is learning how to conduct archival research. This can help you to identify original foundry sources and accurate pattern reproductions for a repair project.


Book your place on Conservation of Ferrous Metals


Entry requirements

Individual modules are open to anyone with an interest in the subject matter. Applicants for the Advanced Professional Diploma should have a relevant degree or professional experience.

Classes, lectures and presentations

  • Material Characteristics of Iron
  • Early Iron Manufacturing and Use in Scotland
  • Traditions of Wrought Iron
  • Traditions of Cast Iron 1
  • Traditions of Cast Iron 2
  • The Scottish Industrial Dimension Corrugated Sheet Iron
  • Iron – Repair Techniques
  • Site Practice and Health and Safety

Potential site visits

  • Bonawe Historic Iron Furnace
  • Traditional iron foundries and forges
  • Kibble Palace reconstruction and Victorian ironwork in nearby Glasgow’s West End
  • Gardner’s Warehouse and other 20th-century Glasgow façades
  • Glasgow Necropolis and Cathedral kirkyard (mortsafes, Edington Gates, restored tombs and Macfarlane Memorial)
  • Glasgow Central Station (façades, gates, canopy)
  • Perth waterworks (earliest iron façade)
  • Forth Bridge
  • Palace of Holyroodhouse, Edinburgh (wrought gates)
  • Fountain Gardens, Paisley (restored 2013–14)
  • Rothesay canopy, Winter Gardens
  • Highland Folk Museum, Newtonmore
  • Louise Carnegie Gates, Pittencrieff Park, Dunfermline
  • Warriston Gates
  • City Heritage Trust sites
  • Conservation Area Regeneration Scheme sites
  • Townscape Heritage Initiative sites
  • Historic Environment Scotland estate schemes

Hands-on workshop/lab activities

  • Pattern-making, or green sand-moulding at foundry
  • Blacksmithing at forge
  • Nick/bend tests
  • Microscopy analysis of metal samples


Material characteristics

  • Metallurgy (iron ore, carbon, phosphorous, silicon, manganese) and characteristics of puddled, grey and ductile iron, and smelting process
  • Types of iron and use in Scotland
  • Wrought iron – purest form of iron and earliest manufacture, artistic traditions revived during Arts and Crafts movement
  • Cast iron – wide range of structural, industrial and decorative uses since mid-18th century, led by Carron
  • Pig iron production, Mushet and blackband ironstone, blast furnaces, Neilson’s ‘hot-blast’ process

Historic use of ferrous metals and the Scottish industrial dimension

  • Innovation and worldwide proliferation in the wake of industrial developments at Coalbrookdale and Carron
  • Success of business models – catalogues, agent system, branch foundries around UK, diversity and flexibility of product line
  • 20th-century decline in iron industry due to alternative materials, lack of investment and changing tastes
  • Impact of wartime salvage operations on historic material
  • Resurgence of interest led by conservation movement from 1970s
  • Corrugated sheet iron origins in late 18th century – used for roofing, cladding and structural formwork for concrete, and pre-fabricated structures
  • Steel – increasingly common from 1880s, eventually supplanting cast iron for structural elements
  • Mild steel – carbon steel used as replacement for wrought iron
  • Stainless steel – chromium-nickel steel, a non-corrosive alloy developed in first decade of 20th century

Properties and characteristics (of each metal type)

  • Malleability and elasticity in production
  • Brittleness
  • Compressive and tensile strengths
  • Thermal conductivity
  • Machinability and recyclability
  • Manufacturing processes – e.g. ores, cupolas, pattern-making, casting, finishing, on-site construction techniques and fixings
  • Lead used for paint and fixing

Repair and conservation

  • Repair issues – from fractures and fatigue to corrosion and use of incompatible materials
  • Project work – from site practice and work sequencing to welding, brazing, filling, pinning, stitching and other repair methods
  • Health and safety issues – e.g. toxicity of paints, dangers of foundry work, welding, heavy lifting, hot lead fixing on site