Final Show III

I am quite satisfied with the redesigned support, both in terms of shape and proportion. The addition of stripes on the surface gives it a more serious and classic appearance, reminiscent of a blend between brutalist objects and Roman columns. However, it also appears extremely challenging to cast. The wall is only 15 mm thick with intricate curves, making it difficult to add any reinforcement inside, and it requires a highly detailed mould. My next task is therefore to find a way to realise it.

Currently, I have two options: first, I could use a silicon and plaster jacket mould, which is reusable; second, I could use a 3D-printed mould. During the Memorial Garden project, I used a 3D-printed mould to create a concrete sample. This sample was thin and curved, similar to my current model, and the mould was able to cast it successfully. Given the time constraints, I think a 3D-printed mould is the better choice as it can be produced faster than a silicon and plaster jacket mould, and I have experience with designing 3D-printed moulds. The only drawback is that it’s not cheap.

However, the process has not been as ideal as I anticipated. The first issue was measurement. The model’s height is around 36 cm and is composed of four parts, but only two printers in the workshop are available for this project, meaning the printing is not as fast as I assumed. Additionally, the success rate of printing is low; during the entire process, it failed more than twice, and each failure cost two to three days. To meet the deadline, I sent another set of moulds back to China for printing. This experience taught me that 3D printing is not always reliable, especially for larger objects.

Despite the time wasted on mould making, I now have two completed sets of moulds. The next step is to test the concrete formula. As I mentioned in a previous journal entry, I have begun experimenting with a mix of cement, sharp sand, glass fibre, and plasticiser, combining these ingredients in specific proportions. However, I did not anticipate such difficulty with demoulding, even though I used Vaseline as a release agent. The concrete model is tightly stuck in the mould, and it simply won’t budge, no matter what method I try. I even had to break the mould to remove the concrete.

Another issue is the texture and colour of the concrete model, which are unusual due to the plasticiser; the surface has an orange tint with a muddy texture. Additionally, possibly due to the sharp sand or plasticiser, the surface is rougher than usual (when using only cement). Fortunately, the strength of the concrete has exceeded my expectations—it is very solid, and the fibres provide excellent reinforcement.