[1] Create something with the vinyl cutter.
The machine I used was a Roland GS-24, and this was connected up with custom mods. 
After weeding part of the structure, I have a hexagonal structure with alternating patterns. Now that I've learned how to utilize the vinyl cutter, I hope to print flexible PCB films with the vinyl cutter. This allowed me to get a good introduction in the process of using these controlled machines. In hindsight, I would have made the file more defined with clear black and white boundaries - the greyscale actually messed up some of the cuts on mods and didn't get cut properly.
[2] Group Assignment: characterize the laser cutter
See group assignment here.
[3] Design and lasercut a parametric construction kit
I never used a laser cutter before, so thinking about how to make a 3D structure from something in 2.5D was difficult at first. Having prior experience in Fusion 360 and AutoCAD, I wanted to try out FreeCAD to check out the alternatives while I was waiting for access.
In the beginning, I started testing out the cutter with contstrained boxes and was able to create a simple box with MIT’s logo. This took a while, since I was still adjusting to the sketch tool. There's a weird aspect of FreeCAD where it's difficult to delete helper lines for boxes when they intersect, and often crashes the program.
After some initial success, I wanted to make an actual construction kit. I was inspired by a variety of unique architecture (e.g., Burj Khalifa), as well as moving objects like race cars. Ultimately, I settled on a biplane, like the Sopwith Camel, with a ~1/100 scale to standard biplanes.
I began by designing the fundamentals of the aircraft – the wings. The first working prototype of the wings, after three of them failed. I was ecstatic after this, since I finally had something somewhat resembling a plane! Getting the joints correctly took some modification of the kerf, but that was eventually solved thorugh the parametric design.
However, I noticed that the wings on the top would be better larger, and this is when I ran into my first issue: constraints. When I set up the Sketch in FreeCAD, I tied the width of the wing directly to the height, meaning that changing them distorted the cutouts used for lining up the wing pieces. When attempting to align joints together. I had to make several boxes with constraints, which got locked and either didn’t delete properly or instead shifted the entire structure, causing frequent issues. I initially took the approach of designing as I went since I didn’t know how to model everything, but after the wings I modeled the rest in one session without any more prototyping. Had I done this all together in one step, it would have been significantly easier.
One interesting design choice I took advantage of was cutting insets into the cardboard at alternating angles in the rudder and fuselage. This was to take advantage of the flexibility of cardboard, as these allowed for movement within the joints. This way, I was able to adjust the rudder and flaps like a real plane!
After 3 hours of trial and error, I got the final cutouts for the files with the correct kerf (I accounted for this using 0.0042 m)
With the parts, it becomes a construction kit you'd get at a science museum! For this plane, I set several parametric functions: (1) kerf for each cutout, (2) the scale of the wings, (3) the scale for the rest of the parts. I kept the scale different for the wings since I was playing around with the height for proportionality. Unfortunately, the file was lost during an Apple Repair, but it should be noted that I made several types of wings that showcase this parametric desig, and tested out 4 separate variants. Here's the final assembly!
[4] Takeaways
In the future, I want to flesh out the body with more flexible pieces in the center. I already started experiencing with alternating cuts 1.75mm apart to make cardboard curve (works very well on the rudder, but not for the fueslage). A flexible piece could allow me to put the seat of the cabin more accurately (and even fit a LEGO minifigure!).
October 10 Update: Looking back at this week, the struggles I had with understanding how each machine worked and how to use it made the other machines I learned a lot easier, and gave me the necessary skills to learn more! I was playing around with the dither setting to engrave images onto wood and acryllic, and a lot of that depended on understanding how the power settings and the speed affected each material.
[5] Files
[3] Design and lasercut a parametric construction kit
In the beginning, I started testing out the cutter with contstrained boxes and was able to create a simple box with MIT’s logo. This took a while, since I was still adjusting to the sketch tool. There's a weird aspect of FreeCAD where it's difficult to delete helper lines for boxes when they intersect, and often crashes the program.
I began by designing the fundamentals of the aircraft – the wings. The first working prototype of the wings, after three of them failed. I was ecstatic after this, since I finally had something somewhat resembling a plane! Getting the joints correctly took some modification of the kerf, but that was eventually solved thorugh the parametric design.
However, I noticed that the wings on the top would be better larger, and this is when I ran into my first issue: constraints. When I set up the Sketch in FreeCAD, I tied the width of the wing directly to the height, meaning that changing them distorted the cutouts used for lining up the wing pieces. When attempting to align joints together. I had to make several boxes with constraints, which got locked and either didn’t delete properly or instead shifted the entire structure, causing frequent issues. I initially took the approach of designing as I went since I didn’t know how to model everything, but after the wings I modeled the rest in one session without any more prototyping. Had I done this all together in one step, it would have been significantly easier.
One interesting design choice I took advantage of was cutting insets into the cardboard at alternating angles in the rudder and fuselage. This was to take advantage of the flexibility of cardboard, as these allowed for movement within the joints. This way, I was able to adjust the rudder and flaps like a real plane!
[4] Takeaways
October 10 Update: Looking back at this week, the struggles I had with understanding how each machine worked and how to use it made the other machines I learned a lot easier, and gave me the necessary skills to learn more! I was playing around with the dither setting to engrave images onto wood and acryllic, and a lot of that depended on understanding how the power settings and the speed affected each material.