Machine Tab Remover
"Design a tooling assembly capable of safely, quickly, and efficiently removing work holding tabs from parts with complex geometries, ensuring no gouging and leaving no more than 0.002 inches of remaining tab material."
For my year-long Mechanical Engineering Senior Design Capstone project, my team and I worked with Accu-Precision Inc., a premier manufacturer of aerospace grade parts for major aerospace companies.
In producing a part, the machinist will program the 4 or 5-axis milling machine to mill out the part from a piece of stock. Then, the last 2 passes made are to produce a small tab, separating the part from the vice grips. The use of a tab is necessary to prevent the part from chaotically flying through the machine once that cut is made. The tab allows the part to be suspended until the machinist comes over and breaks the part free by wiggling it back and forth. The part is freed, but it is never a clean break. There is always tab material remaining on the part.
At the moment, the tab is removed on a grinder wheel; this is a very slow and inefficient process, not to mention unsafe and mistake prone. A clean removal requires at least 5 minutes and it's very easy to slip and ruin an expensive part or harm the operator.
Our machine automates this process, reducing removal process from 5 minutes to about 5 seconds. The machine features multiple safety features to protect the operators on the shop floor and with the precision lift system, it becomes virtually impossible to gouge the part if calibrated correctly. We aimed to achieve a consistent <0.002" of remaining tab height. Our machine exceeded this goal and consistently leaves no more than 0.0005" of tab material across straight and curved parts. With a powerful motor and low runout spindle, the end mill can cut through materials all the way from the softest plastics up to the hardest stainless steels.
The machine is projected to save Accu-Precision multiple $100k per year. Currently, the machine is Patent Pending with a full patent on the way.
On this project, I served as the Project Manager, managing the project timeline, balancing stakeholders interests, organizing tasks, and leading meetings with our client including executives.
Additionally, I took on many technical roles. I designed over 60 components in SolidWorks and created manufacturing part drawings for each of them. I led the electrical system integration of the motor, variable frequency drive unit, and emergency stop. I conducted the tab cutting tests, the FEA analysis of our work surface and frame design, CFD of our chip collector, thermal testing for the end mill and spindle shaft, tolerance analysis for our spindle housing and lift system, and vibrational testing of our spindle housing.
I enjoyed developing new skills in machining, I worked on the manual mill, manual lathe, and taught myself CAM in Fusion 360 to make tight tolerance components on the school's Hurco 3-axis mill.
