CNC Acrylic Centrifugal Pump

Project Overview

This project focused on manufacturing a centrifugal pump housing from stock acrylic using CNC machining. The project required turning raw acrylic stock into a functional pump housing with internal volute geometry, drilled and tapped features, and geometry suitable for final assembly.

The emphasis was on manufacturing execution, process planning, and translating CAD geometry into a successful machined part. This case study details the CAM strategy, machining sequence, process planning, and successful fabrication required to produce the final component.

Role and Scope

The pump geometry was provided as part of the class project. I did not design the pump itself. My contribution was entirely focused on manufacturing planning and execution. I was responsible for translating the provided part geometry into toolpaths, planning the machining operations, and executing the physical fabrication to deliver a finished, functional component.

Final Pump Assembly

Three quarter view showing the completed housing and hose connection geometry.

Side view showing the housing depth and shaft side assembly.

Scale reference showing the approximate footprint of the final assembly.

CAD Geometry

CAD view of the volute geometry used as the basis for toolpath generation.

CNC Toolpath Generation

The core challenge of machining acrylic is managing heat and chip evacuation to prevent the material from melting or fracturing. The roughing operations focused on bulk material removal from the volute cavity, using aggressive but controlled stepovers. Finishing operations required careful consideration of tool engagement and surface speed to achieve a clean final surface on the internal pump geometry. Extensive simulation was performed prior to any physical cuts to validate the tool motion and prevent costly stock ruin.

Machining simulation used to verify cutter motion before CNC execution.

Roughing toolpath used to remove bulk acrylic material from the internal cavity.

Finishing toolpath used to refine the final volute geometry.

Tooling and Process Planning

The machining process used multiple cutter sizes to progressively remove material, refine the volute cavity, and finish smaller internal features.

Larger tools were used for bulk material removal, while smaller tools were used to reach tighter geometry and finish internal features.

Manufacturing Workflow

Outcome

The project resulted in a successfully manufactured acrylic pump housing, complete with all necessary geometries, tapped holes, and mating surfaces. The final part was suitable for assembly as part of the class project and demonstrated capable execution of the manufacturing plan.

Reflection

This project reinforced the critical gap between modeling a part and actually building it. Success required thinking heavily through the sequence of operations, anticipating how the tool would interact with the acrylic material, and recognizing the importance of toolpath verification. I gained practical experience in translating complex internal geometry into a tangible, high tolerance component within a real shop environment.