Artisans Best Friend

About

This project aims to create an easily swappable FDM extruder engineered for different plastics. For example, PLA can melt during heat break and cause a clog. Therefore, when using PLA, the heatsink will have more area to cool off the plastic to prevent jamming, unlike ABS, which does not need as large of a heat sink. Knowing this, we can prioritize increasing the heated area because ABS needs more time to heat up to reach a usable viscosity for 3D printing.

CAD

I was the lead in the CAD production of this prototype. The assembly for this product contains a baseplate that can attach to any 3D printer with at most one adapter. The hot end combines thermal and electronic components working in unison with the heat sink optimized for maximum efficiency. It uses a Fibonacci Spiral to maximize airflow and high and low-pressure gradients to achieve high cooling ratios. It is also a tri-metal heat brake; the aluminum heat sink is bonded to the heater block via 302 stainless steel capillary tubes and ceramic-based glue. Finally, the heater block is copper, which improves the constancy of the heater block and generates a more predictable plastic viscosity.

Analysis

  To determine the optimal heatsink size and material for design, I executed a thermal analysis on the heatsink and heat brake tube to decide on the optimal material. But first, I needed to calculate the convection value manually to simulate the cooling process. The figure below was generated by Fusion 360 analysis software.

Fabrication and Prototyping

The prototypes were first 3D printed to get a sense of scale and then were machined. First, the heat-brake tubes were machined with wire-EDM to cut the stainless steel tube of .25mmthickk walls.

The heatsinks were machined in four operations. Set up, we used where one edge stopper in a vice that was touched off with an indicator. Once the edge stopper was set, all we had to do was run the job. It would have been optimal to run the job with a 5-axis machine running 3+2-axis jobs, where we could have a dovetail fixturing face and remove the dovetail after all operations were complete on a manual mill.

Teamwork/Leadership

This was my first large project at BU. A clear vision needs to be established for all working on a project. It was a critical factor in demonstrating my leadership skills and building upon the skills I already have at a new university. As a leader and good team member,r I needed to be a clean source of communication when Iledd this project. It also showed me the importance of delegation when working on a product and identifying the strengths and weaknesses of my team members to maximize efficiency. A successful team is one where everyone communicates actively and efficiently. A key issue on previous projects was a need for proper communication leading to errors in product development. This project has allowed me to develop my communication skills while bolstering my leadership skills.

Entrepreneurship

Entrepreneurship is about helping people through problem-solving. This project felt personal because I have had issues with fixing and customizing my 3D printers. Therefore, I sought an affordable solution to help advance innovation in 3D printing technology. When conducting a customer discovery analysis,s I found that people want a system that is easy to use/assemble and at a reasonable price. These factors helped drive my design process to create an appealing product.

Logistics

Extruder design was a logistical issue because the cost of production was too high. Extruder fabrication totaled $142 for a production batch of 10. Assembly and production cost an additional $36 if produced in America. When analyzing through a lens of mass production, the Chinese logistics chain and assembly are far more producer friendly than American production. The predicted American production cost was about $200 per unit, while Chinese production had a price of $62 per unit.