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1/4″ Ball Nose Spiral Bit (AstraHP Coated)

Our 1/4″ ball nose spiral bit is used for milling rounded slots, slopes and machining 2D/3D dimensional contours with a smooth finish. AstraHP Coated Solid Carbide Tip diameter: 1/4″ (0.25″) Shank Diameter: 1/4″ Length of cut: 1″ Overall Length: 2-1/2″ Previously SRB4-250UP Made In USA #row-1969876367 > .col > .col-inner { padding: 20px 0px 20px 0px; } #section_1373087588 { padding-top: 45px; padding-bottom: 45px; } @media (min-width:550px) { #section_1373087588 { padding-top: 65px; padding-bottom: 65px; } } @media (min-width:850px) { #section_1373087588 { padding-top: 2px; padding-bottom: 2px; } }

1/4″ Ball Nose Spiral Bit (AstraHP Coated) - Main image
$32.84 $44.99 In stock

Category: Ball End Mill Ball Nose End Mills

Solid Carbide 2 Flute 1/4″ Ball Nose Router Bit.

Used for milling rounded slots, slopes and machining 2D/3D dimensional contours with a smooth finish. Great for milling into all types of material including, wood, plastic, metal etc.

What is a Ball Nose End Mill?

Ball nose end mills, also known as full radius end mills or ball mills, are cutting tools where the nose radius is equal to half of the diameter of the tool. This creates a constant single radius (or ball) at the tool end with no straight edge (sharp corners) in the profile. They are used for contour milling, shallow slotting, pocketing and contouring applications. Ball nose mills are ideal for 3D contouring because they are less prone to chipping and leave a nice rounded edge.

Tip: Use a Roughing end mill first to remove large areas of material then proceed with a ball nose end mill.

Similar to Whiteside RU2075RN.

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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 (5.0 / 5 · 5 reviews)

Mia ★★★★★

Took a chance on this bit for some 3D contour work in hard maple, and it left a surface so smooth I barely needed sanding. The two-flute design cleared chips nicely without bogging down, even on deeper passes.

Samuel D. ★★★★★

The AstraHP coating really does keep the edge cooler, I noticed way less burning on my last batch of maple trim pieces. Two flutes clear chips fast enough that I'm not stopping to vacuum every pass, and the 1/4" ball profile leaves an almost polished curve right off the machine.

Grace X. ★★★★★

Cut a set of rounded slots in walnut with this and the finish off the tool was glass smooth, way better than the straight bits I'd been fighting. The AstraHP coating seems to keep the edge cooler too, no burning on the second pass. Two flutes clear chips fine as long as you don't hog it.