Post-Processing a Large 3D Printed Rocket Component

Post-Processing a Large 3D Printed Rocket Component

Blog Article

Pushing the boundaries of additive manufacturing requires equally advanced post-processing techniques. This walkthrough details the finishing operations performed on a full-build-volume 316L stainless steel aerospace part printed using Trumpf's TruPrint 2000 system with dual 400W lasers. The project demonstrates how hybrid manufacturing combines 3D printing with traditional machining to achieve flight-ready components.

Printing Parameters & In-Process Quality Control

Key Printing Specifications:
- Layer Height: 40μm (double standard resolution)
- Dual Laser Calibration: Automatic deviation correction within 0.001"
- Base Plate Addition: 6.35mm sacrificial material for machining

The printing process incorporated an innovative calibration post that printed simultaneously with the main component. High-resolution cameras monitored laser alignment every layer, automatically adjusting beam positioning when deviations exceeded 25μm. This real-time correction ensured consistent energy density across the 300mm diameter build plate.

Non-Traditional Separation: Band Saw vs Wire EDM

Departing from standard wire EDM separation, the team employed a Hyd-Mech H-16A band saw for initial cut-off. This approach was selected due to:

Cutting Method Comparison:
• Band Saw: 3-minute cut vs EDM's 45-minute operation
• Material Savings: $220 in brass wire per part
• Post-Cut Surface: 250μm Ra ready for facing

The fixture design from previous EDM work proved adaptable to sawing operations. Operators positioned the build plate to protect critical surfaces while maintaining rigid clamping. Surface finishing services later addressed final cosmetic requirements after secondary machining.

Secondary Machining Preparation

With the component separated, attention turned to lathe fixturing. The team developed custom 3D printed titanium jaws matching the part's complex external profile. This approach:

- Eliminates traditional soft jaw machining time
- Provides 0.002" concentricity guarantee
- Withstands 200psi clamping pressure

The upcoming turning operations on the Doosan SMX 3100 will face unique challenges due to the additive material's anisotropic properties. Engineers referenced A356 aluminum properties for guidance in developing suitable cutting parameters despite material differences.

Surface Refinement & Future Applications

The build plate underwent surface grinding to restore flatness within 0.0005"/in for reuse. Residual stress analysis showed:

This data informed the heat treatment schedule (2hr @ 650°C) to stabilize the structure before final machining. The success of this project paves the way for upcoming titanium prints requiring even tighter thermal management during post-processing.