For this project I wanted to cut a lettered emblem. I was really excited to design this because I knew from the get go I wanted to make my metal pieces as shiny as possible. I wanted to challenege myself on post processing material that I did not have much experience with. The post processing steps I took are listed below in the order I completed them in.
- Sandblast
- Angle grind
- Electric Sander (120grit)
- Polish with wd40 and elecrtic sander
- Sanded with grit 150, 320, 400
- Wire brush at 45° angle
- Polish with towel
- Clean with wet towel
Design:
After sandblast:
After angle grind:
After electric sander (2 passes, one with no grease and one with wd40):
After hand sanding:
After wire brush, polishing and cleaning:
The post processing was very straightforward, however, there were some bumps during the cutting process. In my initial file design, I used the trace bitmap feature in InkScape to trace a png of the design that I wanted. I quickly learned, however, that this feature incorrectly translates vectors to whatever program is being used, and the waterjet cannot read the file correctly. I learned this during my test cut about file integrity so the process the second time with the water jet was much smoother.
To get the metal to shine, I used sandpaper, the sandblaster and the electric sander, then a wire brush for a more consistent sheen. The wd-40 made the electric sanding process more efficient so I only had to do a pass or 2. The grease helped with the shine and will protect the metal long term.
This was my workspace after I finshed:
Cost Estimate
Metal: Mild Steel, ~0.9375 cubic inches used, ~$15.55/cubic inch Sandbaggy | $14.58
wd40: White Lithium Grease, ~3oz used, ~80¢/oz Home Depot | $2.40
Sandpaper: 4 grits used, variety pack of grits ~20¢/grit Amazon | 80¢
Wire brush: (1), $1.16 Napa Auto Parts | $1.16
Labor: (8) $10/hr | $80
Total $98.94
