Stackable Geometric Cups

Introduction:

Second assignment for CMPSC 291I. The purpose of this assignment was to create a series of stackable items.

The original example was with basic cups created by rotating a curve around the z axis, however, I wanted to do something different. I wanted to follow this geometric design I saw online and make them stackable. I enjoy looking at geometric ceramics and so I wanted to explore it for this assignment!

It's a very simple design consisting of two hexagons, one larger one at top and one smaller and rotated one at the bottom.

First I created the model's wireframe in Rhino. Disclaimer, I did eyeball most of it and so the actual shape is slightly off. I first created the top hexagon and then created an edge and then replicated the edge 6 times to represent the 6 sides of the cup. Afterwards I used the osnap tool to connect all the lines together to form the shape. Later I then selected each set of 3 lines to make poly surfaces and then tried to wireframe it together. As a small touch, the bottom of the cup is actually not flat and inclines to the center.

I encountered some difficulty here. Although I was using the osnap tool, there were apparently some gaps in some of the surfaces I created. I did some searching and found the "Join" Rhino tool which automatically helps you fill in gaps and connects disconnected pieces together. Afterwards the wireframe worked. I'm really grateful that tool is a feature.

Final object is above!

Building off Jennifer's example code, I modified the inputs and code so that it would work with my geometry instead of a singular curve. I also added a new offset slider so that I could visually see that they could stack by adjusting the slider. It worked well... Until somehow my cups were tilted. (Pictured above)

I couldn't figure out why the code was doing that. I thought it was the bounding box centered position however changing the bounding box center did not help the situation. As a fix, I adjusted the curve used to make the stacking to be aligned with the x axis instead of the z axis.

Rhino and Grasshopper file are here

After I met Jennifer in person (yay) to pick up the printer, I went through a long process of setting up the Ender printer.

Here are the issues and adjustments that were made:

1. Lose z axis limit switch
   1. When I was using the home axis tool, there was also a point where the extruder axis did not stop turning downwards. I had experienced this issue with my personal printer and knew it was something to do with the z limit switch. As predicted, the z limit switch was loose so the machine did not know when to stop going downwards.
   2. It was not feasible to actually fix the limit switch so that it would be held in place because then a lot of the major parts of the printer would have to be taken off because the screws were in the wrong direction (picture 2).
   3. So as a true hackerman, I duct taped the limit switch.
2. Missing bed leveling knob
   1. As seen in picture 3, one of the bed leveling knobs was missing. This made it impossible to accurately level the bed. Again, as a true hackerman, I used the duct taped limit switch previously and manually moved it up or down to follow the height of the corner that was missing a piece.
   2. Thus, if I made the other corners to follow the corner with no knob, theoretically everything would be level. However I don't think that was everything.
3. Printing the 1st calibration cube
   1. There are lines where the filament extruded more than it should as seen from the 4th picture.
   2. I searched online and found out that I should tighten the belt. I also learned that the screws that hold the bed in place were very loose and was causing the bed to wobble as the printer was printing.
4. Printing the 2nd calibration cube (middle cube in picture 4)
   1. As seen from the 4th & 5th picture, I encountered a common problem that I also have encounter with my personal printer - warping. I knew I had to recheck the bed leveling and clean the bed with rubbing alcohol.
   2. The cube to the right is after those adjustments. I believed the printer was good to go at this point.
5. Printer not actually good to go
   1. The last issue was when I was trying to print the largest geometric cup with the Ender. The issue from the first cube was reappearing but this time I wasn't sure what the cause was. I tried investigating the nozzle and asked Jennifer for advice but she suggested it was an issue in the slicing and not the nozzle.

I decided to instead print the cups on my personal printer(Anycubic mega S) for the time being as I wait for the replacement parts to come in. The green is from my personal printer and white is from the Ender.

I did try printing the smallest cup on the Ender again since it would take the shortest amount of time. There is an obvious part of the cup where the printer started to extrude more filament than it should but overall turned out okay.