The Americas Fortifications; Research, Preservation, Assessment and Management
Treatment Option 1: Corrosion Converter & Penetrating Oil
Pros Low initial cost for products & labour Retains surface details
Cons Highest maintenance frequency: 6-9 months Remains tacky for a week‐attracts dirt
Self healing if scratched Good for graffiti resistance
Option 2: Corrosion Converter & Microcrystalline wax
Option 3: Paint System
Tacky surface deters visitor handling Surface preparation & coating can be done by non-professionals, under supervision Low initial cost for products & labour
Reapplication of wax is best done by a professional conservator
Surface preparation can be done by non-professionals, under supervision Medium maintenance frequency: 3‐5 years Retains surface details Graffiti removal has minimal effect on wax coating Lowest maintenance frequency: 10 years
As wax coating wears off, it can blanch and appear white in the corrosion pits
Replicates the original surface finish Extended protection in concealed areas where the metal rests on the support
Scrape in coating – causes accelerated corrosion Graffiti removal often requires repaint of top coat
Highest initial cost
Specialist equipment or operators required for full surface preparation Repeated repainting can obscure surface details
Table 1: Comparison of advantages and disadvantages between the three coating combination options for ferrous metals.
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