15. Wildcard week¶
This week’s assignment is a bit different we need to do something that is not covered in other weeks. Below you can see the assignment from Fabacademy website.
Design and produce something with a digital fabrication process (incorporating computer-aided design and manufacturing) not covered in another assignment, documenting the requirements that your assignment meets, and including everything necessary to reproduce it.
This week we decided to use a plasma cutter machine. A plasma cutter is a machine that uses plasma to cut metals that can’t be cut by laser. I decided to design and cut a tool for our shopbot which was broken.
So, I used Freecad and designed it, then I exported it as a .dxf file. Before cutting we did some test cuts. Below you can see the control panel and software dialog of the plasma cutter.
The software is general software for different kinds of CNCs it uses Gcode. The power of plasma is being set from the control panel manually.
For safety, there are a few rules that are very important to keep
- turn of the plasma cutter before placing a material or taking
- wear safety glasses before turning on the cutter.
The plasma cutter works only with iron the concept is the conductivity of iron.
There are three parameters that you need to keep in mind. The thickness of iron, power, and speed of cutter. Below you can see the table for different thicknesses.
| Thickness | Power | Speed |
|---|---|---|
| 3mm | 30amps | 1000mm/min |
| 5mm | 30amps | 1000mm/min |
| 6mm | 40amps | 800mm/min |
| 8mm | 50amps | 800mm/min |
Here you can see the video of the test cut.
The rench isn’t large the width is 150 mm and the height is 43 mm. It took approximately one minute to cut it.
After doing test cuts and determining the best parameters for cutting I cut the final tool.
After cutting I soothed corners and cleaned unnecessary parts.
