by, Alex Jenkins
This project in E+D 1 was to create a 3D model and 3D print of a toy car to scale. This project focused primarily on replication as the goal will be to accurately represent the toy car. Used CAD (computer-aided drafting) to define a shape in 2D and extrude that shape to make a 3D form able to print. We had to consider the X, Y, and Z planes in a 3D form as the profile from each point of view will define the car shape once printed.
For the process of this project we first started with the design process. We each selected a matchbox car to replicate in Onshape, a 3D modeling software. We started by creating an engineering drawing by sketching, to scale, the outlines of each side of our car onto graph paper to scale. Next, we scanned and uploaded the drawing to github and used the screenshots in Onshape to be used in the 3D modeling process.
The 3D modeling Process: For the next step in our process was to digitally, to scale, render our selected matchbox car. We started by drawing a profile on each plane and mapping out the points on a 3D extruded box that was the outer dimensions of our car. Next, we used the extrusion tools and removed the negative spaces from the 3D form. Finally we used the extrusion and fillet tools for removing all the minor pieces that weren’t included in the outline of the car and added wheels and any other finishing details.
The next step was to export our design from Onshape and import it to Cura. Here we made final scaling changes and positioned our 3D model on the build space to minimize support material. We also set all necessary parameters for the printing process by setting our printer to the labs’ Ultimaker 2 setting at a 0.6mm nozzle. We then exported the file as a GCODE file to removable tabs that were then inserted into the color printer of our choice and printed our models.
The Final step in the process was making this reflection and making sure we had proper documentation. We submitted a CAD drawing with the margin of error analysis by comparing our car’s values to the original ones we documented at the start in our engineering drawing. We then took pictures of our model car next to the original one and submitted it into a slide deck. Our last step is to create this HTML reflection on the project with a 3D render.
A setback I encountered was that I drew the back of my car one block too short on my engineering drawing so the other sides lined up except for the back making the car a bit out of proportion. I fixed it by redrawing half of the back side with one more box so it was symmetrical to the other side which I didn't change and uploaded that image to Onshape.
Another setback I encountered was a 3D printer error where the printer started to just spit out the pla (plastic) in one spot while not moving, creating a glob of plastic instead of a car. I fixed this by ending the print early and starting over (luckily it was early in the process of printing, so not much of a setback).
Here is my 3D render of my car: