Using Markforged’s carbon reinforcement printers, JJ Churchill can print high-precision inspection fixtures in a short amount of time.
The challenge
In order for aircraft to fly true, JJ Churchill (JJC) meticulously inspects every blade of its jet engine turbines. Their coordinate measurement machine (CMM) fixtures must maintain tight tolerances and deflect minimally in order to ensure a high level of accuracy.
Markforged’s material Onyx with continuous carbon fiber reinforcement is the only material that met their requirements of strength and stiffness at an affordable price. These printed parts exceeded all expectations held by JJC regarding part life on the shop floor.
“Once we realized the directional strength properties available with the Markforged products, we haven’t used anything else”, says Manufacturing Engineer Karan Singh.
Traditional manufacturing of CMM fixtures involves multiple roughing and refining operations, which underlie slow iteration and machining wait times. JJC engineers constantly seek innovative solutions to such bottlenecks. They turned to Markforged to achieve major advancements in processes and materials. Combining custom additive manufacturing with off-the-shelf parts enables streamlined production and improved functionality.
Inspection fixtures require enormous time and cost to machine because they must be highly accurate, repeatable, and strong.
The solution
Markforged 3D printers produce complex custom geometries for efficient, secure work holding of valuable low-volume parts. Using these, JJC can design and test fixtures within the same week, with lower material waste and exceptional quality and precision.
By using a non-marring material as Onyx, turbine blades and other components do not get scratched and deemed defective as a result of the inspection itself. Threaded inserts allow screws to apply higher force with lower deformation, and locating dowel pins can press-fit into the printed part to aid positioning. By adding continuous carbon fiber reinforcement along fixture jaws, workpiece deflection is greatly reduced, thus ensuring accurate measurements.