ACMER ASCARVA 4S

About the Machine

The ACMER ASCARVA 4S is a pre-assembled CNC router with a 70W spindle standard, upgradeable to 500W, controlled from an onboard 3.5 inch touchscreen with a manual Z-knob. It has a 400 x 400 mm (15.75 x 15.75 in) work area, runs the X and Y axes on GT2 6 mm timing belts with steel V-wheels and the Z axis on a lead screw, and supports 5W and 10W laser modules, so the same frame can also run as a laser engraver.

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.

ACMER does not publish a spindle RPM for either the 70W stock spindle or the 500W upgrade on the ASCARVA 4S, so check the plate on your spindle before you start and use its actual top speed in place of the chart's number if it runs lower. Depth per pass is where the machine itself matters. 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. The ASCARVA 4S is a pre-assembled, touchscreen-controlled machine built around a small 70W stock spindle, so treat it like a lighter machine and take shallower passes, especially before upgrading to the 500W option. 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. ACMER does not publish a spindle RPM for the ASCARVA 4S, so check the plate on your spindle and use its actual top speed in place of 16,000 if it is lower. 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.