YoraHome Mandrill CNC Router 3036

About the Machine

YoraHome no longer sells this model, but it remains fully supported in Easel. The Mandrill CNC Router 3036 had a 30 x 36 x 5 cm (approx. 12 x 14 x 2 in) working area, a 300W air-cooled spindle motor (ER11-style chuck), acme lead screws, and DM542 stepper drivers. Its controller was an Arduino board running GRBL firmware.

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 Mandrill 3036 ran a 300W air-cooled spindle on acme lead screws. YoraHome never published a max RPM for it, so if you own this machine, check the rating plate against the chart. Acme lead screws are a lighter-duty drive than ball screws and linear rails, so depth per pass is the main thing to watch: a truly rigid machine with a powerful spindle can cut as deep as the bit is wide in a single pass, but a lighter setup like this one needs shallower passes. 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; YoraHome never published a max RPM for this spindle, so check the rating plate on your unit and use whatever it allows, up to 16,000. With the bit maker's 0.025mm per tooth (0.0010 in) at 16,000 RPM: 16,000 x 0.025 x 2 = 800 mm/min (31 in/min) feed. Scale that number down if your spindle's actual RPM is lower. 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.