| The redesigned Hardinge rotary table has a collet-ready spindle for gripping parts of all shapes, sizes, and materials. |
Emphasizing that “part quality begins at the spindle,” Hardinge Inc. has redesigned a low-profile rotary table to give machine operators high-precision gripping capability unavailable with the original design.
“Back in 2008, Hardinge introduced a low-profile rotary table as a standard, no-frills unit to compete against other 210-mm tables on the market,” explained Al Comstock, rotary product manager at Hardinge. “Now, by customer demand, we’ve redesigned the model to include the famous Hardinge collet-ready 16C spindle that provides the high-precision gripping options for which Hardinge is known. We’ve also extended the spindle nose for additional tooling clearance.”
The design is based on the principle that minimal overhang from the spindle bearings will ensure that spindle accuracy is transferred directly to the part being machined. Most rotary tables use a collet adaptation chuck that moves the cutting action several inches away from the spindle bearings.
Hardinge rotary spindles are collet-ready for gripping parts of all shapes, sizes and materials. High-precision gripping options for the GD210LP include standard 16C collets, step chucks for larger diameters, Sure-Grip® expanding collets, and custom collets with the use of an optional collet closer. Special accuracy FlexC™ collet systems, chucks, and the precision-ground faceplate (included) will mount on the A2-5 spindle.
For CNC machine programmers and machine operator, this means that higher accuracy jobs can be run, with less tooling interference, more options for length control, greater internal gripping capability, with no time-consuming fixtures, and lightweight alternatives for a heavy chuck. The additional versatility and the ability to share tooling with other machines in the shop is another significant advantage.
Hardinge states that the enhanced GD210LP rotary table indexer provides rigidity, speed, accuracy, repeatability, and flexibility in an affordable package. High stiffness and super rigidity are accomplished with large-diameter bearings and a fail-safe clamp system allowing part weight of up to 220 lb. Its radial load tests indicated a stiffness of 4x greater than a competitive model. The GD210LP uses up to 233 ft-lb/315 Nm of clamping torque to handle off-center drilling, cross-axis milling and other high-force cutting applications. A fast clamp and release in milliseconds reduces cycle time.
Also, Hardinge states that its hardened and ground steel cross-axis helical gear provides a longer life and continued accuracy compared to softer gears and worm gears found in other brands. Based on true bidirectional testing, Hardinge guarantees ±15 arc-second accuracy and 10 arc-second repeatability.
“With this redesign, all of our rotary products incorporate the collet-ready spindle, states Al Comstock. The Hardinge GD210LP is the most flexible 210mm rotary solution on the market.” The GD210LP operates with a Hardinge servo control or it can be integrated to the machine via fourth axis. Options include a left- or right-hand motor mount, pneumatic collet closer, tailstock and a plate or cube trunnion for machining multiple parts.