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3/8″ Ball Nose Spiral Bit – 1/4″ Shank (AstraHP Coated)

Used for milling rounded slots, slopes and machining 2D/3D dimensional contours with a smooth finish. AstraHP Coated Solid Carbide 1/4″ Shank 1/2″ Cut Diameter 3/16″ Corner Radius 1″ Cut Length Up-cut 2 Flute 2-1/2″ Overall length Recommended RPM: 16,000 Made in USA #row-322638558 > .col > .col-inner { padding: 20px 0px 20px 0px; } #section_1852301926 { padding-top: 45px; padding-bottom: 45px; } @media (min-width:550px) { #section_1852301926 { padding-top: 65px; padding-bottom: 65px; } } @media (min-width:850px) { #section_1852301926 { padding-top: 2px; padding-bottom: 2px; } } #row-607536254 > .col > .col-inner { padding: 20px 0px 20px 0px; } #section_1194061585 { padding-top: 45px; padding-bottom: 45px; } @media (min-width:550px) { #section_1194061585 { padding-top: 65px; padding-bottom: 65px; } } @media (min-width:850px) { #section_1194061585 { padding-top: 2px; padding-bottom: 2px; } }

3/8″ Ball Nose Spiral Bit – 1/4″ Shank (AstraHP Coated) - Main image
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$49.67 $68.99 In stock

Category: Ball End Mill Ball Nose End Mills

This 3/8-inch ball nose spiral bit with a 1/4-inch shank is designed for CNC routing and carving applications. The AstraHP coating enhances durability and performance, making it a reliable choice for your tooling needs.

  • Ball nose geometry for smooth, rounded cuts and detailed contouring.
  • Spiral flute design helps efficiently evacuate chips during operation.
  • 1/4-inch shank fits most standard CNC routers and handheld routers.
  • AstraHP coating provides added surface hardness and heat resistance.
  • Compatible with a variety of materials, including wood and soft composites.
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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.4 / 5 · 5 reviews)

Joshua M. ★★★★★

I've been running this bit through some pretty tough hardwood on my CNC, and the AstraHP coating is making a real difference in heat buildup and chip evacuation. The ball nose geometry cuts a clean, smooth contour without any chatter.

Miles ★★★★★

Cut a batch of walnut with this and the edges came out glassy smooth, no sanding needed on the curves at all. The 1/4-inch shank fit my collet perfectly with zero wobble, and the spiral flutes clear chips way better than the straight bits I was using before.

Violet P. ★★★★★

The AstraHP coating has held up way better than the plain bits I used to burn through — still slicing clean after a dozen or so projects. The 1/4-inch shank fits my router collet with zero wobble, and the 3/8 ball tip leaves a really smooth finish on rounded edges.

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