TUTORIAL 1 - THE BOWL

The Bowl 

This week’s task we were required to make a bowl using a metal sheet. The purpose of this task is to understand how to transform a simple piece of sheet into complex shapes by shrinking and stretching the material. Shrinking and stretching the material will significantly change the overall area of the material. 

Firstly, Russell explained the theoretical aspect of shrinking and stretching metal. He emphasised on the idea that once we commence hammering the material we will ultimately shrink the metal sheet and reduce the overall surface area. In addition to allow for a smooth surface we would need to stretch the material using the English Wheel, however this will not impact the surface area tremendously. He also gave us a tip, which is to trace the bowl template onto the Aluminium sheet using a marker pen, this step helped be cut the sheet more precisely when utilising the tinsnips. 

Secondly my group and I moved to Martin station, in which he specialises with all laser cutting machinery.  He explained the different functions the laser machine can do, for example he cut a bowl template and ‘Female Radius Gauge’ using plywood. The bowl template consisted of four centric rings, which will give me a guidance of where I should hammer the metal sheet (as shown in figure 1.1 below). Similarly, the ‘Female Radius Gauge’ was also given to us with four different radius dimensions. I aimed to achieve r155 (shown in figure 1.2). In order to achieve this, I continuously rested the ‘Female Radius Gauge’ on the underside of the bowl, until I was satisfied with the result and ensured no gaps were visible.  

Figure 1.1 - This is a Bowl Template which shows four centric rings.
Figure 1.2 - This is a Female Radius Gauge’ template (Both Templates are composed of Plywood) 

Once I received both templates from Martin I was next stationed to Daniel who showed us how to physically shrink the aluminium using the nylon mallet. He explained we would need to hammer from the inside than out, which will eventually form the metal sheet into the bowl shape.  I learnt when shrinking the material using the Nylon Mallet it creates tucks, which can be smoothed out using the rounder side of the Mallet. 

Finally hammering the bowl ultimately gives it a rough finish, thus Gabe showed us how to smooth out any bumps, in which the English Wheel is the best tool to rectify this issue. Furthermore, the edges of the bowl were quite rough, so I used a file to smooth it out, this was time consuming however rewarding.  

Low and Bird Eye View

Side View

Female Radius Gauge shown to match my bowl - r155