Hello Again! This week we’ve been working on creating personalized plasma cut pieces with well documented post-processing steps. The first step in this project was personalizing the design. Everyone in the class was tasked with modifying the same diamond shape. I did some brainstorming and eventually decided I wanted to do something with curves, and created a wave shape to cut. Once my design was finalized, I used the plasma cutter to cut out three copies, enough for 2 final copies and one for trial and error. Two of these pieces can be seen in Figure 1.
Figure 1: Freshly Plasma Cut Pieces!
Once these pieces were cut, I had to figure out how I wanted my finished pieces to look. I knew that I did not want to spray paint them because I liked the natural metal look and I wanted to have a more unique set of pieces; many of my classmates seemed to be using spray paint. After this I also decided that I wanted to try out using the varied grit sandpapers to see what result that would give me. However, before I could get to that point, I needed to prepare the pieces a bit more. Ths began with angle grinding all surfaces to get rid of the dross (melted metal bits left on the plasma cut pieces) and to flatten the surfaces. In figure two you can see a untouched piece compared to a angle grinded piece.
Figure 2: Untouched vs. Angle Grinded Metal Pieces
After this I still had to even the surfaces a bit more, so I proceeded to the sandblaster. I sandblasted each part until the surfaces had the distinct matte look. These pieces can be seen in Figure 3.
Figure 3: Sand Blasted Metal Pieces!
At this point I was ready to use the different grits of sand papers. I started at 150 and worked my way up to 1000. In this process I learned a couple things: 1. Metal dust will get everywhere, 2. Sandpaper will make the metal shinier, but not that much shinier, and 3. The lines from the angle grinder were still visible. From this point I knew I was not at a suitable finishing point. I liked the shininess that the sandpaper gave to my pieces, but they just weren’t strong enough to cover up the still slightly uneven surfaces of my pieces. So, in order to make the pieces shinier, I proceeded into the machine shop to use the buffer. I buffed the pieces, and this did make them extremely shiny and smooth, but, unfortunately, the lines from the angle grinder were still visible. This effect can be seen on the piece in Figure 4.
Figure 4: The shiny, but not too smooth piece
At this point I was definitely not satisfied with where my pieces were at. After thinking about it for a while, I decided that given the steps and outcomes I experienced getting to this point, it would not be possible to give the pieces that shiny chrome finish without much more time and effort. Instead, I came up with a new final design: using the laser cutter to etch a design into the pieces. In order to begin this new process, I first re-sand blasted the pieces to take away the uneven shininess and make them uniform again. Then I proceeded to find a design to etch into my pieces. To keep with the curve look of the original design, I looked for a geometric design with circles. Once I found one I liked, I used photoshop to cut the original picture down to just the shape of my pieces. This design can be seen in Figure 5.
Figure 5: The design to be etched into my pieces!
Next, I actually etched this design in. For this step I had to use the fiber laser (rather that the CO2 laser), which was new to me, and because of that was interesting to use. I began by cutting a piece of wood in the shape of the general diamond design to create a place to put my diamond such that the laser already “knows” where it will need to cut – removing any error experienced from the diamond not quite lining up with the lasered design. After this hole was cut, I etched my pieces! A picture of the completed pieces can be seen below.
Figure 6: The Completed Pieces!
This project has definitely been the most challenging so far. Although I didn’t see the results that I had anticipated through using the sandpaper and buffer, I’m glad that I got to try them out and see some of what they could do. These issues also taught me that you can always backtrack and start over if you really need to, and that the sandblaster is very forgiving to these issues. Overall, although it was quite the journey, I am very satisfied with how my pieces came out and I am thankful for all that I learned on my way to getting them there.
Finally, I’ll do a quick cost estimate. For material costs, I found a metal supplier where you can purchase a square foot of 1/16″ aluminum for $9.72. For labor costs, I worked for 6.5 hours, and at $20/hr, this adds up to $130. In total, the production cost of this piece is $139.72.
