APG Revolutionizes CNC Workholding with 3D Printed Chuck Jaws

When Alpha Precision Group (APG) of Ridgway, Pennsylvania, introduced its first metal 3D printer in 2018, it aimed to experiment with metal injection molding (MIM) iterations and create more durable CNC workholding fixtures. This venture quickly turned into a valuable business opportunity, both for APG’s internal machining needs and for external customers.

Innovative Chuck Jaw Workholding Assembly

APG’s early exploration of metal 3D printing led to the development of a chuck jaw workholding assembly for turning cam gears. This innovation, now patented, is being marketed to external users as a 3D-printed alternative to traditional solutions.

Lightweighting with Bound Metal Deposition

The legacy workholding solution involved heavy jaws machined from mild steel, weighing 2,100 grams. These required significant clamping pressure to counteract centrifugal force during turning, often deforming the gears.

Using its first metal 3D printer, a Studio system from Desktop Metal, APG redesigned the chuck jaws using bound metal deposition (BMD). This method builds green metal forms using polymer filament with metal powder, which are then debound and sintered. The BMD process allows for greater geometric freedom and cost-effective metal printing.

APG reduced the material in the chuck jaws by incorporating lattice structures and bridging features, resulting in a lighter solution. This redesign cut the clamping pressure requirement from 30 to 15 psi, reducing gear deformation.

Advanced Optimization with Moldjet

APG further optimized the design with its Dominant 3D printer from Tritone Technologies, which uses the Moldjet process. This process prints wax molds filled with metal paste, layer by layer, which are then melted away and sintered. Moldjet allows for highly complex geometries and high productivity with up to six build trays running simultaneously.

The Moldjet-optimized chuck jaws weigh just 492 grams, a 77% reduction from the original. This lighter design saves material and boosts productivity by enabling faster spindle speeds during turning operations. Although the cycle time impact is minimal due to short cuts, the design promises higher sustained spindle speeds without clamping force reduction for customers.

APG’s adoption of advanced 3D printing technologies has revolutionized its chuck jaw manufacturing, offering significant weight reduction and enhanced efficiency. This innovation highlights the transformative potential of 3D printing in industrial applications.

Original source MMS