16. Wildcard Week¶
Wildcard Week gave us a chance to step away from our usual assignments and explore something completely different. It was an opportunity to expand our toolkit and experiment with processes we hadn’t tried before. I chose to dive into metal laser cutting because I haven't had much experience with metal tools and machines before.
Understanding the basics¶
What is Metal Laser Cutting?
Metal laser cutting is a way of cutting through metal using a powerful laser beam. The laser is so focused and hot that it can melt, burn, or vaporize the metal in a very precise way. This method is used to create clean, accurate shapes from metal sheets without touching them directly.
How Does It Work?
- A high-energy laser is generated using a special source like fiber or CO₂.
- The laser is tightly focused onto the metal surface to create extreme heat.
- The heat melts or burns through the metal along the desired path.
- A jet of gas clears away the molten metal, leaving a clean, precise cut.
Metal laser cutting¶
We don't have metal machines in house so we sourced it from the local vendor from outside. This is the machine that we used.
At first, I planned to try waterjet cutting. However, I found out that it’s generally better suited for cutting thicker materials and isn’t the best option for very detailed designs. As my design had intricate details I decided to go with laser cutting instead.
Cutting Thickness Capabilities:
Laser Cutting
- Kerf for the metal lazer cutter - 0.2mm
- Stainless Steel (SS): 0.5 mm to 8 mm
- Mild Steel (MS): 0.5 mm to 16 mm
Designing¶
After discussing the project, we asked the vendor which file format the machine would require and we got to know that Dxf file would work, so I quickly prepared my design in that format.
I started by designing my file using Adobe Illustrator, which I am familiar with. I created two horses—one representing a positive and the other a negative cut. These abstract shapes were meant to symbolize the bond between a mother and child. The contrast between the solid and hollowed-out forms visually conveys the idea of interdependence.
I merged my design with my fabmate Samrudhi’s file to create a combined cutting file.
Toolpath¶
For making the toolpath we used cypcut software which is similar to rdworks software of laser cutting which I had used earlier. Download the software from the link provided here
Getting Started
First, power on the laser cutting machine and the computer running the CypCut software. Make sure both devices are properly connected through USB, Ethernet, or another compatible interface.
Importing Your Design
Open the CypCut software and import your design file. The software accepts common formats like .dxf or .svg, which are standard for 2D laser cutting.
Setting Material and Machine Parameters
Select the metal type you are working with, such as steel or aluminum, and enter the thickness of the sheet.
Based on this, adjust the laser power, cutting speed, and gas pressure for optimal cutting results.
An interesting point I noticed is that while speed is adjusted much like in regular laser cutters, the laser power depends on the type and amount of assist gas used. Oxygen can cause black marks and rough edges, whereas nitrogen provides cleaner cuts with no residue.
Configuring Lead Lines
For the Lead-In, choose the type of entry—either straight or arc. Then, set the length so the laser has enough distance to reach full power before it starts cutting the actual design. If needed, adjust the angle for straight lead-ins.
Next, for the Lead-Out, select the type, again either straight or arc. Set the length to make sure the cut finishes smoothly. Adjust the angle if applicable. Finally, position the lead-ins and lead-outs so they begin and end outside the main cutting area to avoid marks on the final piece.
Adjusting Compensation Settings
Next, go to the compensation settings. Input the kerf width — this is the material removed by the laser beam. Decide if the compensation should be internal or external depending on whether you want the cut inside or outside the design line. You can choose between automatic or manual compensation.
Additional Settings
Double-check that lead lines and compensation are correctly applied to all paths. Then, run a simulation within CypCut to preview the toolpath and ensure everything is set properly.
Generating and Transferring Toolpath
Once satisfied, generate the toolpath file in formats like .nc or .cnc. Transfer this file to a USB drive and plug it into the laser cutter’s controller.
Cutting process¶
Preparing the Machine
Load the toolpath file on the machine and set the cutting speed and feed rate based on your material’s thickness. Set the XY origin by aligning to a corner of the bed or the reference point used in your design.
For the Z origin, use the paper method: lower the cutter until it touches the material, raise it slightly, and place a thin piece of paper underneath. Adjust the height until there is just a slight friction when moving the paper.
Start Cutting
- Ensure all safety protocols are in place (e.g., wearing safety glasses, securing the material).
- Start the cutting process from the machine's controller.
- Monitor the process to ensure it runs smoothly.
The material I used is MS: 3mm. So according to the material we changed the nozzle, this is how the the nozzle of metal laser cutting looks
After changing the nozzle we adjusted the origing and checked the frame for cutting and then the cutting started.
Final Piece
Hydraulic press: Vessel¶
While walking around, we came across a fascinating process happening in one corner of the workshop. A large flat metal sheet was being transformed into a huge container. Two people sat facing each other, skillfully rotating and pressing the sheet as it gradually took shape. It required a lot of skill, strength, and coordination.
We were surprised by how such a big 3D form could come from something so flat. It was a completely manual process, and it showed us another side of working with metal – something we don’t usually get to see.
Paper pulp packaging¶
For this week I also explore molding and casting techniques by creating a secondary packaging out of paper pulp. The aim was to create secondary packaging that is both sustainable and custom-fit for a small product. I chose paper pulp as my casting material because it's biodegradable and easily available.
Designing the Mold¶
- Instead of a regular two-part mold, I designed a three-part mold in Fusion 360. Here's why:
- The bottom and top parts formed the main cavity shape.
- A third side slide allowed me to add texture on the side of the casing.
- This side slide could be easily removed, making the casting and demolding process smoother.
Later I realized the dfm part as the printing the slide wouldn't be convinient so I sliced the sides. The side sliders were my favorite part — they slid in smoothly from the side and added a unique texture that I had designed. They also made the mold 3D printer–friendly by avoiding complex overhangs.
3d printing¶
All six parts were printed in PLA using standard settings. I did a test printing first to make sure that the mold is correct.
Final mold printing
Making the Paper Pulp¶
Creating the paper pulp was an essential part of my project, as it served as the material for casting my sustainable packaging. I used waste corrugated which is used in packaging to make the pulp from scratch, turning scrap into something useful.
I shreded the waste corrugated added water and tried to grind it but I was not able to grind it.
So next, I placed all the shredded paper into a large bucket and added enough water to completely submerge the paper. I let it soak overnight (6–8 hours). This softens the materal so that it would be easier to grind.
Once the paper was soft and soggy, I used a blender to break it down into pulp. I blended the mixture in small batches with extra water to keep it from overheating. The consistency should be thick but smooth — similar to oatmeal or clay.
Next To help the pulp stick together when dry, I added fevicol. (You can also use rice paste) in 1:3 ratio.
For easier casting, I drained some of the water using cloth.
Tip: Don’t remove all the water — you still need some moisture for shaping.
Casting¶
Once the paper pulp was ready, the next step was to cast it into the mold I had designed and 3D printed. I assembled all the mold parts tightly together. To ensure no gaps or leaks during the casting, I used clamps around the mold. These clamps held the parts together with enough pressure to give the final packaging a neat and defined form.
Note: Proper clamping was very important because the paper pulp is wet and can leak or warp if the mold isn't fully sealed.
I took the mixture and filled the cavity slowly and carefully, pressing the pulp in layer by layer to make sure there were no air pockets or loose areas.
Once the mold was filled, I left it clamped for drying.