3D Scanning and Printing¶
Goals¶
Group assignment:
- Test the design rules for your 3D printer(s)
- Document your work on the group work page and reflect on your individual page what you learned about characteristics of your printer(s)
Individual assignment:
- Design and 3D print an object (small, few cm3, limited by printer time) that could not be easily made subtractively
- 3D scan an object (and optionally print it)
Prior Knowledge¶
I 3D printed several objects in my first engineering class, and CAD is second nature at this point. This should not be especially difficult, although I am somewhat unfamiliar with testing the 3D printer.
3D printing is referred to as additive manafacturing, which creates work through the addition of material. 3D printing is the main type of additive manafacturing, although there are different machines and methods of doing so. In contrast, subtractive manafacturing refers to creating work through removing material. CNC milling, laser cutting, and sculpting are common examples of this method.
Projected Timeline¶
- Wednesday
- Start individual assignment
- Thursday
- Finish individual assignment
- Friday
- Document
- Saturday
- Start group assignment
- Sunday
- Work on group assignment
- Monday
- Finish group assignment
- Tuesday
- Document assignments
Actual Timeline¶
- Wednesday
- Start individual assignment
- Thursday
- Start group assignment
- Friday
- Restart group assignment print
- Restart individual assignment print
- Correct previous documentation
- Saturday
- Document assignments
- Sunday
- Get ahead on final project
- Monday
- Collect 3D prints
- Finish documentation
- Tuesday
- Plan for next week
Group Assignment¶
I was in a group with Amalia Bordoloi and Cooper Cumbus. I was assigned the torture test.
You can see our documentation on our group site.
Individual Assigment¶
Plan¶
I would print the golf cart, however, I don’t have all the dimensions scaled. I also find it a bit premature considering I would need to account for microcontroller storage, axle fit, wheel fit, and likely more variables that will emerge in the coming weeks.
I decided that, since I could not create a house with small windows and stairs inside through subtractive manafacturing, I would 3D print one. This house would be for the mini golf course and be extruded the bottom to allow a press fit.
Model¶
Modeling the house was not terribly difficult. I based it off of the thumbnail of this Fusion tutorial, although I did not watch or follow it.
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Shape
- Sketch 2.5*10 rectangle
- Extrude .1 inches
- Sketch on top
- Offset -.5 inches
- Extrude outline 10 inches
- Sketch on top of outline
- Create rectangle with same dimensions as shape
- Extrude .1 inches
-
Windows
- Sketch on front of shape
- Create vertical construction line at midpoint
- Create symmetrical 2.4*1.2 rectangles towards top
- Create 2*1 rectangles in center of each
- Create symmetrical cross with each rectangle .1 inches wide in center
- Extrude outlines -.3 inches
- Extrude cross -1.4 inches
-
Roof
- Sketch on side of house
- Create line along top
- Extend line by 2 inches on either side
- Create 5 inch vertical line upwards from midpoint
- Connect either side with top of line
- Extrude 10 inches across top of house
-
Door
- Sketch on front on house
- Create vertical construction line at midpoint
- Create 2*3.5 rectangle on bottom symmetrical across line
- Create 2.6*3.7 rectangle on outside with overlapping bottom line
- Extrude outline -.3 inches
- Sketch on front of door
- Create circle with .3 inch diameter towards left
- Extrude .1 inches
-
Stairs
- Split body at roof
- Disable roof visibility
- Extrude top -.5 inches
- Sketch on floor
- Create 2-point 1.4*.35 rectangle from top left corner
- Repeat until there are 8 rectangles total
- Extrude second rectangle .1 inches
- Add .1 inches for every successive rectangle
- Keep 8th rectangle same height as 7th
-
Second floor
- Sketch on top of highest rectangle
- Make 2 point rectangle with same dimensions
- Extrude .1 inches
- Extrude right side to right wall
- Extrude bottom side to bottom wall
- Extrude left side of new platform to left wall
-
Roof modification
- Sketch on top outline
- Create rectangle of same dimensions
- Extrude .5 inches
- Enable roof visibility
- Sketch on front of house
- Sketch vertically symmetrical triangle
- Extrude 2 inches
- Extrude across other roof, choose join
- Extrude other side 2 inches
- Sketch on front of roof
- Offset -.5 inches
- Extrude -..75 inches
- Repeat last 3 steps on other side
-
Chimney
- Disable roof visibility
- Sketch on first floor
- Sketch horizontal line of symmetry across floor
- Create 5*3 rectangle symmetrical across line with right side and right side of wall overlapping
- Extrude 17 inches
- Sketch on top
- Offset -.5 inches
- Extrude shape -16 inches
-
Scale
- Use scale factor of .5 to the origin
- Use scale factor of .5 to the origin
3D Print¶
It occured to me that, frankly, 3D printing this would not be ideal for my golf course. I would rather cut a house without stairs on the inside and paint it as opposed to a random filament color. I cut the press fit extrusion I originally made to attach to the course. Still, I decided that this is a helpful design to understand the layout of the houses I will place.
I followed the same steps as I did for my group assignment.
-
Slice
-
Print
The first print failed using the Prusa, the design was most likely thrown out because I could not find it to take a picture. Mr. Dubick recommended I try the Bambu for efficiency, and I found that it was in fact easier.
Cooper Cumbus in my group made a helpful workflow that I followed.
I used tweezers to remove the supports. I used the normal setting as opposed to the tree, so my main challenge was “unwrapping”. I also realized the importance of scaling; while most aspects turned out well at a 30% scaling ratio, when removing the support from the window on the right, I accidentally removed the entire inside shape. This proves that smaller objects, while faster to print, sacrifice reliability. Otherwise, though, the print turned out well.
3D Scan¶
I sought out a 3D scanning software and found PolyCam. I decided to scan my computer mouse since it was small, simple, and right next to me. The software was fairly intuitive. I held the camera stil and let it take 25 images, just over the minimum of 20.
While the scan was quite detailed, I learned that I need to rotate my camera to capture every angle. Otherwise, it shows up as blank space. I see this being useful for quick prototypes.
Reflection¶
Group Work¶
Printing the torture test was not complicated once I used a printer that best fit the job.
Positives¶
The CAD this week was simple. 3D printing a small house requires neither large curved surfaces nor calculated scaling, which are my main difficulties. The payoff is always rewarding with the printing of unique geometries in a matter of hours, if even.
Negatives¶
Since most prints take longer than a single period, I worked around my schedule to check on them. The printer choice influenced several of the steps I took, and neglecting to edit certain settings could result in a failed print. I needed to familiarize myself with the G-code configuration and signs of a working or failed print.
Takeaways¶
While I’ll most likely 3D print storage for microcontrollers and hidden fasteners, I learned that I would like to rely on cutting and milling to preserve the realism of my project. Also, I am unsure how the press fits would differ with a 3D print and cannot take chances.
Advice¶
- To connect to a printer, you need to connect to their network and access the link. Also, keep the login credentials for printers saved in an easily accessible document.
- Ensure that the nozzle, plate, and heat settings comply with the printer. If not, the print could fail. Of couse, check other settings as well, but they are most likely fine unless otherwise stated.