Nosecone
Development
See my design process as I work on an ongoing project as a part of Citrus Racing's Aerodynamics sub-team, applying my skills to develop the manufacturing process of the car's nosecone and create a streamlined process for the layup production of future large scale carbon fiber pieces.
The Job
I began with a SolidWorks 3D model already composed by my team leads. It then became myself and my team's job to find a way to manufacture this roughly ~3ft.-5ft, nosecone out of carbon fiber, using a mold. The first step to that process was developing a mold from this model.
Our First Idea
Our initial idea was to divide the model up into smaller pieces, creating three sections (allowing for the final to be sectioned gives access to the cockpit, as opposed to one whole non-disassemble-able carbon piece) then 3D print each of the pieces out, assemble them like LEGO's using integrated tabs along the seams, and lay the carbon-fiber up on inside, with the molds being negative. I drew up this diagram to ideate and visualize what needed to be done.
Creating the Layers
As soon as we got our idea situated I jumped into SolidWorks to figure out how we could turn our model into more bite-sized printable pieces. I discovered that with the split tool, I could use planes to splice the model into as many layers or pieces as we needed. So I divided the nosecone into five layers, each consisting of at least 4 printable sections.
Creating the Tabs
After creating the layers, I explored using the Lip/Groove feature in SolidWorks to create the tabs on each of the layers, to ensure our mold fits together seamlessly. I applied a lip and a groove to two of our layers, and sent them in to our team leads to be printed in our makerspace.
In the Meantime...
While we waited for the test layers to print, our team moved forward in making a smaller scale prototype of the nosecone, using the same process we would for the full-scale, so we would know exactly how the process would go when laying up the real thing. We began by mocking up silhouette strips of each of the sides of the nosecone with tape, so we could cut the corresponding shapes out of the carbon fiber fabric.
Inlaying the Carbon
After cutting out each of the sides of the nosecone, we inlaid and sealed the carbon fiber to the inside of the mold using 77 series.
Rigging for Resin
After that, using a combination of mesh, plastic tubing, detachment fabric, tape, and a plastic seal, we rigged the prototype mold for resin filling. We tested the vacuum seal, and ensured that it was ready for resin. After all this was finished though, it had been a long day, so we pushed resin testing back to another day.
Analyzing the Test Prints
Come our next workshop, the test prints had finished, so we were able to analyze them to see what went right/wrong/if they would work. As it turned out, assembling the mold in this way would present too many potential discrepancies between prints and surface levels, so we need to find another way to build these layers without compromising any surfaces. So for now, it's back to the drawing board. As I continue to work on this project, stay tuned for more updates...
