Watery Blue - Bronze Patination
 

Description

Beautiful deep patterned bronze patina. This is one of the most straight forward and effective patina's that I use. The patterning can range from delicate and very subtle, through to a dense rich colour with a tight texture. The pattern is hand formed and the key ……is the subtlety of application and this takes practice. The informal naturalistic patterning can easily become opaque or clouded, by either overheating or overloading with chemical, one simple run can ruin the whole patina.

Metal Preparation

Silicon bronze sanded to a even 120 grit
 

Base Coat Chemical

  1 - 2 teaspoons of Liver of sulphur ------- 1 litre of water

Apply this solution to the bronze and look for the reaction, it should be a gentle transition of colour. If the colour changes dramatically, then dilute the solution until you get a gentle transition.
 

Base Coat Application

Warm bronze very gently, apply the weak solution of liver. You want the bronze to change colour gradually, continue applying solution to develop a good even colour. Rinse the surface thoroughly with water and a brush, this removes some of the residue and helps to neutralise the chemical reaction. Heat the bronze until a fine dusty film appears on the surface, remove this carefully with 120 grit scotch brite pad or other appropriate soft abrasive. The basecoat needs to be an even colour, with a hint of bronze just showing through.

1st Colouring Coat chemical solution

Water ----- 250 ml
Strong Copper Nitrate solution ------ 3 - 4 teaspoons
Additional Fixative ----- Weak sodium silicate solution

1st Colourcoat Application

Heat the bronze evenly, the solution should just sizzle and evaporate away as you apply it with a natural haired paint brush. Take small amounts of solution into brush at each application, as the brush warms up it natural sucks the solution up into the brush. The oxide that forms on the surface of the bronze should develop into a strong intense blue green colour. The oxide at this stage remains delicate and can easily be over heated and turn yellow. The trick with this patina is the patterning, this is acheived by getting the bronze temperature absolutely even across the area you are working, a cold patch will run and over heated area will turn yellow and opaque. The actually patterning formed on the bronze is achieved with a round sable brush, the brush needs to be used, so the hairs are slightly misshapen which helps to achieve a very natural look to the pattern. Rotate the brush on each application of chemical, this helps to break up any rhythmical lines or patterns forming. Methodic heating and chemical application will result in a very even, intensely coloured and a final patina with depth and clarity.

Sealing Solution

Sculpt Nouveau Smart Coat - 1K Polymer Sealant

Application

When the bronze is at room temperature, we use soft cloth or brush to apply 3 coats, letting them fully dry between applications. 

Highlighting

To add additional colour to highlight areas, we mix a small amount of pigment with a small amount of sealant and use a sponge or brush to add this mixture.

Darkening Shadowing

To create shadows or to darken areas we use a graphite wax, this is thinned down with a clear wax to create a translucent paste. This is applied both under final wax layers or over the final wax layers.

Final Wax layers

We use renassiance wax for the final waxing. Its applied with a soft brush in a very thin layer, left for 10 mins and buffed to a hard finish. We add three or four layers, with the final layer buffed to the final finish.