DN Solutions (Doosan) Mynx 6500/50

DN Solutions Co., Ltd. is the renamed successor to Doosan Machine Tools. In 2021, the Doosan Group divested the machine tool business to an MBK Partners private equity fund. The company was renamed DN Solutions in 2022. DN Solutions maintains the same manufacturing facilities in South Korea (Seongnam, Changwon), the same product lines (Mynx VMCs, Puma turning centers, NHP horizontals), and the same global service network. The name change was a rebranding rather than a fundamental business change. Parts, service, and support for all machines sold under the Doosan Machine Tools name are fully supported by DN Solutions.

The spindle taper number refers to the ISO/ANSI taper size at the spindle nose — a larger taper number means a larger, more robust tool holder interface. 50-taper (BT50/ISO50): larger tool holder, greater contact area with spindle, designed for heavy cutting in steel and cast iron with large-diameter tools (50–200 mm face mills). Maximum tool holder weight typically 20–30 kg. 40-taper (BT40/ISO40): smaller, lighter tool holder, faster tool change, designed for smaller tools and higher RPM precision work. 50-taper provides more torque transfer at the spindle-tool interface — critical for heavy roughing operations. For large VMCs like the Mynx 6500/50 doing die/mold work, 50-taper is standard and appropriate.

Box ways (or sliding guideways) use precision-machined flat or V-shaped surfaces in contact with corresponding guiding surfaces, with a lubricant film providing the sliding interface. Box ways provide: very high load capacity (resist large cutting forces in all directions); excellent vibration damping (the lubricant film absorbs vibration energy); and high stiffness under cutting load. Linear guides (ball-bearing based) provide lower friction for faster traverses but have less load capacity and damping. On the Mynx 6500/50, Y and Z axes use box ways for the maximum rigidity that die and mold roughing requires, while the X-axis uses linear guides for faster table repositioning between cuts.

The Mynx 6500/50 machines all standard mold steels: P20 (pre-hardened 28-34 HRC, most common plastic injection mold steel); H13 (hardened to 48-52 HRC for die casting and hot work tooling); S7 (shock-resistant tool steel for trimming dies); D2 (high-carbon high-chromium cold work steel for long-run stamping dies); 420 stainless mold steel; 17-4 PH stainless; and aluminum tool steels (7075-T6, Al 7050) for prototype and low-volume injection mold tooling. For hardened steel (48+ HRC), carbide insert milling with good coolant is required. The box-way rigidity and 50-taper torque capacity support aggressive material removal rates on hardened steel that lighter VMCs cannot achieve.

Maximum table load is 2,000 kg (4,409 lb) distributed across the table surface. For a single workpiece centered on the table, 2,000 kg is the limit. For tombstone fixtures or multi-workpiece setups, the total weight of all fixtures and workpieces must stay within 2,000 kg. A large P20 mold base (1,200 x 600 x 400 mm) weighs approximately 2,300 kg per cubic meter of steel — a mold this size at these dimensions (calculated as 0.288 m3) would weigh approximately 670 kg, well within the table limit. Very large multi-piece die sets may approach the limit — calculate workpiece weight before ordering to confirm the machine specification meets your heaviest planned workpiece.