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Whiteside #8 Countersink Bit

Whiteside 4 Flute, 82-degree Adjustable #8 Countersink, High Speed Steel, 3/8″ Outside Cutting diameter, 11/64″ Inside Diameter (for 11/64″ center drill), for countersinking holes for a #8 size screw. Wood Screw size: #8 Countersink Diameter: 3/8″ Made in USA Replacement tapered bits available

Whiteside #8 Countersink Bit - Main image
$19.59 $27.99 In stock

Category: Workshop

Whiteside 4 Flute, 82-degree Adjustable #8 Countersink, High Speed Steel, 3/8″ Outside Cutting diameter, 11/64″ Inside Diameter (for 11/64″ center drill), for countersinking holes for a #8 size screw. These Whiteside #8 countersinks are designed to slip over the drill bit and affix with dual set screws into the flutes. Adjust the drilling length by sliding the head up or down the bit. Use to countersink holes in wood, plastic, or aluminum for flat head screws. High Speed Steel series for longer life, especially in fiberglass or other abrasive materials. Sold together with the Taper Point Drill #8 which is ideal for better control on entry and exit. The Taper Point resists the rapid pull-in tendency of gelcoat and other hard, thin materials. They also break through less abruptly, which helps reduce blowout on exit.

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Customer Reviews (4.6 / 5 · 5 reviews)

Zoe ★★★★★

The 4-flute design cuts smoothly without chattering, and the adjustable depth stop saved me from guessing on every hole. I used it on some oak shelves and got clean, uniform countersinks for all my #8 screws.

Chloe L. ★★★★★

The four-flute design makes a clean, chatter-free cut even in hardwoods, and the adjustable depth stop is dead-on once you set it. I’ve used it on a dozen oak shelves and every #8 screw sits flush without any tear-out.

Avery C. ★★★★★

I was a little skeptical about an adjustable countersink, but the 11/64″ center drill hole fits my pilot bits perfectly. The four flutes leave a smooth finish without any chatter.