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5/16″ Down-Cut Spiral Bit – 1/2″ Shank – Whiteside RD4850 (AstraHP Coated)

AstraHP Coated Solid Carbide 5/16″ cutting diameter 1/2″ shank 1″ length of cut Down-cut 3” overall length Recommended RPM: 16,000 Made In USA #row-1019626921 > .col > .col-inner { padding: 20px 0px 20px 0px; } #section_2125806046 { padding-top: 45px; padding-bottom: 45px; } @media (min-width:550px) { #section_2125806046 { padding-top: 65px; padding-bottom: 65px; } } @media (min-width:850px) { #section_2125806046 { padding-top: 2px; padding-bottom: 2px; } }

5/16″ Down-Cut Spiral Bit – 1/2″ Shank – Whiteside RD4850 (AstraHP Coated) - Main image
AstraHP Coated Whiteside RD4850 5/16" down-cut router bitAstraHP Coated Whiteside RD4850 5/16" down-cut router bit
$62.04 $84.99 In stock

Category: Down-Cut CNC Bits

This Whiteside RD4850 down-cut spiral bit is designed for clean, chip-free cuts in CNC routing applications. The 5/16-inch cutting diameter and 1/2-inch shank provide stability and precision, while the AstraHP coating helps reduce friction and heat buildup for longer tool life.

  • Down-cut spiral geometry pushes chips downward, minimizing tear-out on the top surface of your workpiece.
  • 5/16-inch cutting diameter suits detailed trimming, grooving, and finishing passes.
  • 1/2-inch shank fits standard CNC collets and router chucks for secure mounting.
  • AstraHP coated flute surface enhances wear resistance and aids in chip evacuation.
  • Whiteside brand quality ensures consistent performance for professional and hobbyist users.
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Customer Reviews (5.0 / 5 · 5 reviews)

Henry ★★★★★

The 1/2-inch shank gives this bit rock-solid stability even during deep passes, and the down-cut spiral leaves zero tear-out on plywood. I've been running it at 18,000 RPM without any vibration or deflection.

Leo ★★★★★

The AstraHP coating on this bit really helps the chips eject cleanly, and I haven't had any tear-out on my plywood edges since switching. Makes a huge difference for crisp inlay pockets.

Richard ★★★★★

I was skeptical about spending this much on a single bit, but the down-cut spiral design really does produce noticeably cleaner edges on thin plywood without any tear-out. It fit securely in my collet with zero runout.

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