Adapting an ancient Japanese technique for preserving timber

Snakey Grass PassSnakey Grass PassSnakey Grass PassSnakey Grass PassSnakey Grass PassSnakey Grass Pass

The process of burning timber at extreme temperatures to produce an elegant, weather & pest resistant finish.
Early in the design process for our recently built play space at the CERES Adventure Habitat, we experimented with material finishes for the Desert Ash (Fraxinus oxycarpa) logs which formed the basis of the design competition and therefore was the primary material at our disposal. We found the timber to be relatively soft and attractive once cut. As the timber weathers it develops a silvery grey patina which has a certain appeal but not what we were looking for. We tried a number of finishes looking for something that would be durable enough to withstand the elements without excessive need for costly maintenance or the application of harsh chemicals. Charring was tested on a small sample using an oxy acetylene torch and we were immediately encouraged by the results for two predominant reasons. First, the burning process rounded all sharp corners and left a very pleasing child friendly surface, a significant factor to consider when designing for play spaces. The second factor was the aesthetic quality of the burnt timber. The burning process revealed qualities of the timber that were not visible before intense heat was applied.

The process is as follows:

  • Remove all bark from timber, including any 'under-bark'. The helps the flame penetrate into the timber releasing the carbon required for prolonged preservation
  • Scorch timer with an extremely hot flam. We used an oxy acetylene welder with the cutting torch. Ensure that a deep burn is achieved
  • Wash and scrub timber with water to remove all excess carbon deposits. This needs to be done when the timber is still hot
  • Once dry apply multiple coats of Tung oil. The oil will draw out the deep black colour from the burnt timber
  • Client: 
    Emma Hicks
    Sarah Hicks
    Share via Twitter Share via Facebook