For our plasma cutting assignment we were asked to plasma cut the first state in America. I chose New Hampshire since I went to a summer camp at Dartmouth College and lived there for a month in my junior year in high school.

The first step of all is to download and modify the state vector file. The New Hampshire fire was nearly perfect and all I needed to do was removing the worlds and the box, and leaving only the contour of the state.  Then we used Torchmate to export a DXF file that specifies a path to cut with the plasma cutter. One thing we noticed is that the plasma cutter is less accurate than the laser cutter because the path that Torchmate generated is pretty much an approximate contour of the state.

After importing the file to the plasma cutter, making configurations, zeroing the axes and pressing the start button, we just need to watch the plasma cutter doing its work! (The plasma cutter gave me a shock when it started with its strong spark.)

The product out of the cutter is a very raw part with slags on the edges and rust on both surface (as you can see from the picture). So the next step is post-processing to make it look nice. After clamping the part onto the working desk, I first used a file to clear the slags on the edges, and used a dremel to make it smooth. To clear the rust, a nice piece of sandpaper is pretty much enough, and I scrubbed both sides of the part in vertical and horizontal directions with the sandpaper, otherwise there would be ugly scratches in one direction.

After clearing the part, I decided to apply different colors on the sides (lime and white). For each side, put the part on a flat cardboard and smoothly apply can spray from 1-2 inch away to the left of the part and go all the way to 1-2 inch to the right. Then wait for about 3 hours and take it inside the room and let it completely dry in 24 hours.

I first applied the white paint and then lime. The problem is that after I applied lime and left OEDK, someone moved my part from its original place, and the white side was contaminated by the lime paint on the cardboard. I tried to scratch the layer of lime paint off but ended up removing pieces of paint of both white and lime. So I have to apply white paint again, and it was not that smooth due to scratched pieces. (See the top part of the white paint)

The plasma cutting and post processing assignment is a very interesting hands-on experience for me. I wish I could use the sand blaster as well but I did not want to try it on painted surface, hopefully I get to use it in the future.