YCM QP Series VMC

The QP Series is designed from the ground up as a pallet machine — the pallet seating, location, and clamping surfaces are integral to the machine structure, providing more consistent pallet repeatability than bolt-on APC systems. Aftermarket APC systems fitted to standard VMCs sometimes have pallet seating accuracy lower than the machine's own axis accuracy; the QP's integrated design maintains pallet repeat accuracy consistent with the machine's ±0.003 mm repeatability specification. The integrated APC also has faster pallet change time and a simpler mechanical design than most bolt-on systems.

The QP Series offers pallet sizes from 400 x 400 mm to 500 x 500 mm depending on the model configuration. In practice, a 400 x 400 mm pallet accommodates parts up to approximately 350 mm in any direction (allowing for fixture and clamp clearance). Complex multi-part fixtures can be mounted on each pallet, allowing each pallet cycle to produce multiple finished parts. Shops running families of smaller parts often build tombstone fixtures or multi-vise setups that maximize pallet density and produce 4–8 parts per pallet cycle.

The dual-pallet QP Series can run lights-out only for the duration of the two pallets already loaded — when both pallets have completed their cycles, the machine waits for an operator to reload. For extended lights-out production, shops typically couple the QP Series with a robot loading system or a pallet pool automation system that Fanuc's robot interface enables. YCM supports robot integration on the QP Series through the Fanuc 0i-MF Plus control's standard robot interface M-codes. For fully unattended overnight production, a 4-6 pallet pool or robot cell integration is needed beyond the base dual-pallet machine.

The QP Series pallet change cycle (from machining on pallet A to machining on pallet B) is approximately 8–12 seconds depending on model configuration. This compares favorably to most bolt-on APC systems (typically 12–20 seconds) and provides a smaller fraction of non-productive time in short-cycle programs. For programs with 10-minute cycle times, an 8-second pallet change represents 1.3% of machine time — negligible. The pallet change overhead becomes more significant in very short-cycle (2–4 minute) programs where even 10 seconds represents a meaningful percentage of the cycle.

The Fanuc Robodrill D21MiB5 is a compact, high-speed arm-type machining center optimized for very short cycles and high tool change speed in small workpiece applications — a different design philosophy than the QP Series. The Robodrill is smaller (travels around 300 mm in X), faster (10,000 RPM with optional 24,000 RPM), and designed for 1–5 minute cycle programs on small parts. The YCM QP Series offers larger travel (500–760 mm X), larger pallet capacity, and BT 40 rigidity for medium parts and heavier cutting. The Robodrill wins for very small, short-cycle aluminum work; the QP Series is better for medium-size parts and heavier-duty programs.