10 Jul The Top Ironwork Finishes for Rust Prevention and Durability
Wrought iron is a durable and rust-resistant metal commonly used in landscaping and fences. Unfortunately, if not protected from the elements, iron will corrode and discolor quickly.
Wrought iron can be given a number of finishes that protect it from corrosion and enhance its aesthetic appeal. Here are some popular choices for your next project.
Powder coating is the go-to for many metal products and components to prevent rust and enhance durability. This process is used on everything from outdoor furniture to commercial equipment like cranes and trailers – perfect for protecting metal products against weathering!
Powder coats are applied electrostatically to the surface of an object, creating a bond that is much thicker and harder than paint, explaining why powder-coated ironwork lasts so much longer compared to painted pieces.
Additionally, paint helps prevent oxidation – the source of all rust problems. Once painted metal objects such as fences become vulnerable to surface corrosion from substances like slag, flux, and coal that remain on the surface.
Sandblasted ironwork finishes provide your custom pieces with a polished, weatherproof appearance that resists corrosion. They’re more durable and consistent than paint, making them perfect for outdoor metal fabrications such as handrails and gates.
Sandblasted ironwork, unlike paint, lacks brushstrokes or bubbles. Its smooth and consistent surface makes it the ideal finish for decorative items.
Rust can be a real hassle to deal with. But if you take precautions, it may be an issue that is easily avoidable.
Instead of waiting for natural rusting to happen, you can speed up the process and create your own chemical patina. This is an efficient and economical way to add a rich rust patina finish to metal items such as punched-tin lanterns, wrought-iron candlesticks, or steel picture frames.
As atmospheric moisture and sulfur compounds interact with copper oxide (Cu2O), a blueish or green patina forms over it. This layer primarily consists of copper sulfates such as posnjakite (Cu4SO4(OH)6) or brochantite (Cu4SO6(OH)2) with some chloride ions present.
Copper patina layers are relatively stable and serve as a protective layer for the underlying copper. How long it takes for them to form depends on environmental conditions and atmosphere; typically five or seven years in coastal or industrial settings, while rural areas may take much longer or never form altogether.
Blackening is a commonly used finishing process for ironwork and steel that adds protection and longevity. It’s an economical and effective way to add a protective coat to metalwork.
There are various methods used for blackenings, such as cold blackening and hot blackening. Before either method begins, however, some preparation must be done on the surface to prepare it for blackening.
The hot blackening method involves submerging steel in a hot bath of sodium hydroxide and nitrites, turning the metal surface into magnetite. This gives the metal an authentic black appearance that cannot be replicated through painting alone.
Oil or Wax
Traditional smiths usually finish iron with either wax or metal oil. Drying oils such as boiled linseed or tung oil are preferable to raw linseed oil, and it’s best to thin the oil before applying it to the iron for improved penetration.
Regular inspection of metal objects should be conducted to monitor rust progress and re-oil as necessary. Oil gives iron objects a shiny sheen, acting as an effective vapor barrier that inhibits rust from occurring.
Store iron objects in a dry environment with low RH (see CCI Notes 9/2 Storage of Metals). Avoid storing artifacts near other materials that could damage them, such as wood.