1/32" Fishtail Down Cut

ID: D07

Type: End Mill

1/32” cutting diameter, a quarter the size of every other bit here. A pink plastic band on the shank marks it as Inventables’ own fishtail line. Fishtail geometry gives a flat-bottomed cut without the small center nub a plain square-end or ball-nose leaves — Fusion’s tool schema has no distinct fishtail type, so it’s modeled as a standard flat end mill (RE=0); the toolpath math comes out the same either way.

Specifications

Property Value
Cutting diameter 0.03125” (1/32”)
Shank diameter 0.125” (reduced-neck)
Flutes 2
Cutting length 0.200”
Overall length 1.500”
Geometry Down cut spiral, fishtail tip
Corner radius None — square end
Material Solid carbide
Coating None

Feeds & Speeds

For the X-Carve Pro and its 1.5 kW spindle. Computed from first principles, not scaled from any bit already in the shop — at this diameter, breakage risk from lateral load governs everything, not spindle torque or power. RPM stays flat across the wood tiers rather than dropping for harder material the way bigger bits do, since torque was never the limit here; only feed and stepdown change with material. Real-world reference: a hobbyist on a much weaker desktop CNC (10,000 rpm ceiling) settled on roughly 16 ipm cutting 1/8” plywood with this exact bit — the numbers below sit in that same range, adjusted up slightly for the X-Carve Pro’s greater rigidity.

Material RPM Feed Chipload Plunge Stepdown
Hard maple / oak 18,000 14 ipm 0.0004” 5 ipm 0.015”
Soft maple / walnut / cherry 18,000 16 ipm 0.0004” 5 ipm 0.015”
Plywood / veneered sheet 18,000 18 ipm 0.0005” 5 ipm 0.015”
MDF / laminate 18,000 20 ipm 0.0006” 5 ipm 0.02”
Softwood / pine 18,000 20 ipm 0.0006” 5 ipm 0.02”
Acrylic / HDPE 14,000 14 ipm 0.0005” 5 ipm 0.01”

Notes

Maximum cut depth is 0.2”. That’s the entire cutting length — there’s no headroom to push past it the way a bigger bit tolerates a little overreach. Cutting through 1/8” plywood (0.125”) is within reach in several light passes; anything thicker needs a bigger bit for the bulk of the material and this one only for the fine detail pass.

Extremely fragile — treat it like it will break, because it will if pushed. A 1/32” carbide shaft has almost no lateral strength. The stepdowns above are a fraction of what every other bit in the shop uses, on purpose. Clear chips constantly (vacuum or air), and never let the toolpath dwell or reverse direction under load.

Always ramp — never plunge, same downcut chip-packing rule as everything else, but the consequence is worse here: a packed 1/32” flute doesn’t just heat up, it snaps.

Fine detail and inlay work only. This isn’t a bit for clearing material — it’s for the last, finest pass on lettering, small inlays, or anything a 1/8” bit is too blunt to resolve.

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