The 3-D printed vacuum trim tool. Photo courtesy of Ingersoll
US-based Ingersoll Machine Tools
and Bell Textron
, have completed a collaborative effort using a large format 3-D Printer to successfully manufacture a 22ft long vacuum trim tool for the production of main rotor blade components for helicopters.
The project utilised Ingersoll’s hybrid large format MasterPrint gantry-type 3-D printer and five-axis milling machine at the company’s base in Rockford, Illinios.
Chip Storie, Ingersoll CEO, said: “We are continuously testing and advancing MasterPrint in our development centre. Among Ingersoll’s short-term objectives is for MasterPrint to 3-D print moulds for aerospace that preserve the geometrical properties and tolerances, vacuum integrity and autoclave resilience normally obtained with traditional technology, but with the cost and time reduction only additive manufacturing can offer. The relentless progress our MasterPrint process has made in 2020 has finally made this target attainable.”
This production tooling effort 3-D printed 1,150 pounds of ABS material with 20% chopped carbon fibre fill. The 3-D printing process was completed as a single part in a continuous 75hr operation. After printing, the mould surfaces and tooling location features were machined to finished dimensions by exchanging the print module for the five-axis milling head which is changeable on the MasterPrint machine.
The machining was completed in one week and the final part achieved full vacuum tightness. The Ingersoll machine utilises the Siemens 840D CNC control system for controlling both the machining and the 3-D printing.
Critical time savings were achieved through the 3-D print fabrication and efficient five-axis machining operations. The additive and subtractive manufacturing processes were seamlessly co-engineered in the native CAD software format.
The traditional build cycle for a typical mould in aluminium, using standard methods, is typically four to five months — this 3-D printed manufacturing process was completed in a matter of weeks.
James Cordell, process stability senior manager at Bell, said: “For many years Bell has used composite materials for manufacturing airframe components, including components produced on an Ingersoll Machine Tools Tape Layer machines.
These similar materials are now being used for manufacturing the moulds that form the airframe components. Using this rapid manufacturing equipment will allow Bell to greatly accelerate our development of tooling for many applications within the Bell organisation.”