Lunyee 4040 Turbo

About the Machine

The 4040 Turbo is an all-metal CNC router with a 400 x 400 x 110 mm working area, a 500W spindle (a 1.5 to 2.2kW water-cooled spindle is available as an upgrade), and NEMA 23 stepper motors. It drives all three axes with optical axis guides paired with lead screws.

Cut Settings on this Machine

Every cut starts with one formula: Feed Rate = Spindle Speed (RPM) x Chip Load x Number of Cutting Edges (flutes). Chip load is the thickness of material each cutting edge removes in one revolution of the bit. This number comes from the manufacturer of the bit, which publishes a chip-load chart for each bit diameter and material. Look up your exact bit and material, start from the middle of the published range, and you have the third number in the formula. The chart below shows the recommended spindle speed for each material and bit type.

The 4040 Turbo ships with a 500W spindle as standard, with a 1.5 to 2.2kW water-cooled spindle available as an upgrade for harder cuts, but Lunyee does not publish a max RPM for either option, so check the plate on your spindle before you set chart speed. This machine's NEMA 23 motors and optical-rail, lead-screw drive give it more mass and torque than Lunyee's smaller 3018 and 4040 Pro routers, but depth per pass still comes down to rigidity, not spindle wattage. A truly rigid machine with a powerful spindle can cut as deep as the bit is wide in a single pass, but that takes real spindle torque, a drive train and clamps that hold firm, a gantry that will not flex, and enough mass to soak up vibration. Start conservative and work up: push too deep and the bit deflects and chatters, leaving scalloped edges, or it rubs instead of cutting and burns the material. The fastest way to dial in a cut is to see what has already worked for other people.

Worked example for feed rate: 1/8in (3.175mm) two-flute solid carbide end mill in hard wood. The chart says 16,000 RPM. Lunyee does not publish a max RPM for this machine's spindle, so check the plate on your spindle and use its actual top speed if it is lower than 16,000. With the bit maker's 0.025mm per tooth (0.0010 in): 16,000 x 0.025 x 2 = 800 mm/min (31 in/min) feed. For depth per pass, start shallow and check Community Cut Settings in Easel for what works on this machine. If the cut sounds strained, reduce the depth, not the feed. Slowing the feed below the chip load makes the bit rub instead of cut.

Community Cut Settings shows the spindle speed, feed rate, and depth per pass other makers actually run for your machine, material, and bit.