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The treatment was taken under the guidance and support of Grimwade teaching staff, Dr Paula Dredge John Hook, and Dr Jonathan Kemp, with special credit to Dr Jonathan Kemp, who sourced the tear repair equipment (Pine 64) under the Master’s course in Cultural Material Conservation at the University of Melbourne. 

The Church Painting 1, possibly painted in 1889 by an unknown artist, is framed with a four-membered wooden frame. Together with Church Painting 2 is the collection of St Columb’s Church Hawthorn. The owner sent the painting to the Grimwade Centre of the University of Melbourne as a teaching and research object. The painting was in poor condition, with a major tear of approximately 300mm noted at the top right of the canvas.

Prior to the major tear repair, dry cleaning, pH and conductivity testing, and other treatments were conducted. The torn area was humidified in a controlled approach and then flattened with blotter paper and weights overnight. The tear of the canvas was repaired by bridging the gap with foreign fibre. Natural adhesives pose a threat to insect and microorganism attacks, which might not be suitable for future storage. The heat-activated synthetic adhesive, polyamide welding powder, was used to repair the tear. A mixture of original fibre extracted from the canvas and new linen fibre was chosen as the bridging threads.

As suggested and provided by Dr Jonathan Kemp, lecturer at the Grimwade Centre, the low-cost heating needle, ‘Pinecil’ of the brand Pine64, is originally a mini portable soldering iron used in repairing electric circuit boards. The set temperature of the solder ranged from 100 °C to 400 °C, which is lower than other soldering irons (usually starting from 250 °C). In order to figure out a suitable operation temperature, the polyamide powder was first applied to the mock-up canvas with the heated needle set at different temperatures. At a set temperature of 120 °C, the polyamide powder started to melt but was too rigid to apply. A set temperature of 140 °C was tested as the minimum temperature for the polyamide powder to melt thoroughly and become flexible to apply. The tip of the apparatus is exchangeable and supported with different sizes and shapes. The high temperature might be a concern to the canvas; however, during the application, the needle should not contact the canvas directly (adhesive in-between), and no observable change in the mock-up canvas was noted after the application.

The molten adhesive first adhered the original canvas and one end of the foreign thread together. Tightened (tensioned) the thread with a micro pointed tweezer and applied the molten adhesive to the other end of the thread. The treated area was then left dried under weight for minutes. The tear was successfully secured in place with fibre and polyamide welding powder.