This is a technical guide to metalwork finishing options to help you arrive at the most suitable final look of your project. You may want to read this guide in conjunction with the materials blog.


This gives you a large number of colour choices, apart from the commercial options we have developed some metallic black finishes that look very good on forged metalwork. Surface preparation is very important and for external work steel should be protected through hot zinc spraying or galvanising prior to painting. Advantages are that work can be easily touched up after installation, disadvantages are cost and sometimes durability.

Powder coating

This is a harder, more durable finish than painting. Surface preparation is again important and a high zinc primer is a cost effective alternative to the hot zinc options. There is a large range of powders available, including some attractive metallic options. Advantages are speed, cost and durability. The hardness does mean that natural warmth and earthy feeling finishes are not achievable.


This is a specific treatment for aluminium. It protects the metal from corrosion, it hardens the surface and it is available in a range of colours.

Chemical blacking

This is a hot submerged process with some nasty chemicals, mainly used on small components. We would not recommend it on larger items as the cold applied methods are less effective and hot tanks are not large enough for architectural purposes. We can blacken items up to about 1m in length in a kiln for a similar effect.


This is a labour intensive process with grades ranging from brushed to super mirror. A practical shiny surface for architectural purposes is somewhere between a commercial mirror and a super mirror finish. Electro polishing is more cost effective and very suitable where the surface texture wants to be retained but it will not achieve a full mirror finish. Polishing looks best on stainless steel, brass or bronze. Aluminium can be polished but will quickly tarnish and steel is too prone to rusting.

Commercial hot processes

There are a number of proprietary stainless sheet steel finishes, which include different colours and textures for cladding purposes.

Traditional hot processes

Hot forged ironwork can be heated and wire brushed, before being waxed to protect it from rusting. This gives a beautiful deep sheen that metallic black paint and powder finishes basically try to emulate. It is obviously only suitable for interior use.
Heat can also produce tempering colours on polished stainless steel, ranging from a straw yellow through purple and blue to black. This can either be done with a heat torch to create a rainbow effect or in a large kiln to create more consistent colours. Consistency on some colours can be hard to achieve, depending on the heat range that produces the required colour.

Metal Plating

This is the opposite of electro polishing, a thin layer of metal is deposited on the underlying work. The recommended base for this is polished stainless steel, which means that it is possible to achieve shapes that are not otherwise practical. Finishes offered include chrome, nickel, brass, copper, bronzes, rose gold and more. There is often a significant cost saving over making the work in the actual material. The downside is that the thin decorative layer and subsequent protection can make it look overly shiny. Any scratches will show the base material and can not be repaired.


We define a patina as controlled ageing, or oxidization, of the metal. On steel the only practical patina is a light brown rust, which can be sealed under wax or lacquer. Stainless steel is specifically designed not to rust and we are not aware of any decorative patinas on aluminium. Where the patina process comes into its own is on copper based alloys: between copper, brass and bronze we can create red, green, blue and a large range of brown patinas. There is a limit to the number of even colours that can be achieved but if you include the variegated finishes the options run into the hundreds.
There are some commercial patina solutions which will create cold applied brown to black finishes. We have however found that hot submerged techniques give a more durable and even finish, which we will typically seal under a layer of wax to retain the rich natural look.
Our current tank capacity is up to 3m x 1.5m x 0.5m.