Post 9: Top 5 Specifications, Top 5 Constraints

To judge my project success, I have come up with a list of my top 5 specifications that I would like to achieve with my artifact. They are:

  1. The project functions
  2. The symbolism elements in the final product come out well
  3. The colors I use have a vibrant appearance
  4. The project is able to assemble the way that I have planned
  5. The final artifact is a size which is big enough to be appreciated yet not too large for a desk space

Ensuring the functionality of the project is not an easy task. To do this, I made a couple of design decisions that will improve the final product’s gear train functionality. Gears prove somewhat difficult to model using certain CAD software, since a perfectly matching pitch is required for them to mesh correctly. To make sure my gears work, I found CAD models for spur gears on McMaster Carr, which I have edited with my desired final design. This was just to make sure that I get properly sized gears with the correct pitch. I have also added slots to the support arm structure, which gives me a way to adjust how the teeth between gears will mesh together by sliding the rotation axis along the slot. Additionally, I will set bearings into the middle of each gear to allow them to rotate smoothly.


To make sure the symbolism comes out well, I am 3D printing my parts with a precision machine that will be able to nearly perfectly mirror my CAD models. To give my colors a vibrant glossy look, I will use white filament, and use a glossy spray paint on the parts to give them a smooth finish. Assembling the final product should be straightforward, since I used CAD to design the whole assembly together. This is also how I will ensure that the artifact is of the correct size, and representative of my original plan.


My top 5 constraints will be:

  1. Time
  2. Finding a high quality 3D printer
  3. Designing the astronomical symbols in CAD
  4. Hardware selection
  5. Gear sizing

As with many projects, time is a difficult constraint. 3D printing, while relatively quick, can still take many hours, and sometimes even more if a print fails or a part needs to be redesigned. Since I do not personally own a 3D printer, it may also be difficult to find one that is capable of making my parts in the exact way that I would like. Since the astronomical symbols are somewhat freeform, flowing shapes, designing some of them accurately in CAD may be a long process with imperfect results. As I plan to use hardware from existing CU resources, finding hardware with the correct size and finish may also prove difficult. Finding bearings of the correct size will also be a potential challenge. Finally, gear sizing is somewhat limited by what I can find on McMaster Carr. I will have to make sure that the pieces I select will fit well with my planned size for the project.

Previous Post
Five Specifications and Five Constraints to Build a Bird House
Next Post
Top 5 Specifications and Constraints: Minimalist Interchangable Photo Collage

1 Comment. Leave new

  • Travis Mulford
    May 8, 2024 10:23 am

    Hello Sam,
    The gears seem like an interesting problem to solve for this project. I like how you took the models off of Mcmaster-Carr and modified them, that is a creative solution. How do you plan on finding a high resolution 3D printer to print these parts?


Leave a Reply

Your email address will not be published. Required fields are marked *

Fill out this field
Fill out this field
Please enter a valid email address.