A Study in Form II
10/21/16
This week I started to apply what I’ve been learning about craft and materiality to a process that was not based around creating with wood for the finished product. I designed a tray to go with the tea light holder that I had created on the lathe earlier (A Study in Form I). Instead of creating the final piece out of wood I learned how to use a vacuform machine and mold plastic.
The process began with making a mold. A particle board disk was cut out with the drill press and then a pre-provided pattern was taped to the disk. Using the jigsaw I cut out the center of the disk, following the pattern, in a circle to fit the base of the tea light holder that I had previously created.
When cutting out the interior circle I learned that I really needed to take into consideration the volumes and shape of my mold. I also needed to take into consideration the type of materials that I would be using to create the form that I wanted and the nature of fit within the piece that I was molding. I had to angle the saw table to cut the circle out with the proper draft angle around the edge, so that later on when the piece was used to mold plastic on, I would be able to get the plastic off after it cooled.
After cutting the circle and sanding the sharp edges a bit (to ensure that the tea light holder would have a smooth sliding fit and not have to be forced into this tray), I traced the pattern on to a larger square of the particle board material. I did this to give myself a guide to drill small draft holes in the board, so that when I turned on the vacuform machine it could suck air through the holes and tighten the plastic on to my mold properly. I learned that in the process of making the mold I really had to think backwards about what I was making, envisioning a shape that I wanted and then figuring out how to make it’s inverse (though admittedly this had already been figured out for me in this case and I was just following pre-provided directions). In the exercise of making the mold it was extremely important to understand the nature of how the materials would react against different surface characteristics not only for the fit of the mold, but also for the fit of the two separate finished pieces (tea light holder and tray) to each other.
After drilling the holes I then fastened the circle to the center of a larger square piece of the particle board material. I took a 12x12 piece of plastic and duct taped it to a 12x12 form to put under the heater for melting over the mold. Once again at this point, being able to understand the nature of the material was critical. The plastic began to bubble up as it was heated and I had to know just exactly when the right softening of the material had happened for it to be pliable enough to mold. As a novice vacuform user I needed a little help from someone with a bit more experience and practice to know when the plastic was ready. There weren’t any hard and fast measuring tools for temperature or softening of the plastic, it was something you simply had to have the expertise and practice to look at and intuitively know.
After taking the plastic piece off the mold I once again used the pre-made pattern to stencil on the shape of the base that I wanted with rounded corners. I cut off the basic square of the base using the band saw but it left the plastic with very rough unfinished edges.
I then used the disk sander to sand off the rough straight edges and round off the corners. Once again I had to use my intuition and knowledge of the material to follow the stencil lines that I had drawn and fillet the corners all evenly. I did not have a precise way to measure this at all. This also required an understanding of the tool, knowing that with the sander at full power the plastic would quickly melt away. Only when sanding on the slow down without power would the sander have the correct amount of force for me to be able to properly control the finish that I wanted on the edges.
The finishing touches for the piece were to drill a whole into the center of the base and anchor the tea light holder with a small screw, as well as to add to stick on feet to the corners of the tray.
Overall I was a bit unsure about this part of the process. This was because of the idea of mixing the wood and plastic mediums. They are very different forms of making and I do wonder if the addition of the plastic takes away from the beauty of the wood carving. Also sticking on little plastic peel-off feet seemed like it took away from the thought and skill that went into the creation of the form. My final pieces together looked like this:
This exercise really made me think about understanding the differences in materiality and how they dictate the way in which something is crafted. They can each withstand different types of force in different ways from the machines. It takes a knowledge of the behaviors and properties of the different materials to be able to anticipate how they will react to different types of machine and human manipulation. They cannot also be measured and accounted for exactly all the time. Conditions always vary and it’s necessary to be able to manipulate and work with a material by ‘eye’, which is something that takes time and experience to perfect. The process of vacuforming also made me particularly aware of understanding the piece in 3 dimensions as well. Sometimes as the craftsperson you must design through modeling or in the case of molds, reverse modeling. The craftsperson has to be able to think three dimensionally about the different attributes of the piece before actually starting to make it so that they know how to approach the fabrication and can visualize the way everything will fit together in the end. This also allow them to better make adjustments and improvisations throughout the craft process.
