79mm Long Drill Bits | McMaster-Carr

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25 Products

Drill Bits

Cut holes in a variety of metals, from the softest aluminum to the hardest steel.

High-Speed Steel Jobbers' Length

Round Shank

Split

Our basic drill bit material is also the most versatile. These jobbers' bits have the balance of rigidity and length needed for most applications.

Gold Oxide—Like black oxide, this finish adds wear resistance and reduces friction for improved chip flow. Because it’s less prone to flaking off, it offers better rust protection when bits aren't in use.

Round Shank—The most common shank type. These fit in the chuck of drill presses and portable drills.

Split Point—Starts cutting on contact so you don’t need a pilot hole. The point also keeps the bit centered for straight and accurate holes, even with a portable drill.

						Shank						Each
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes	Specs. Met		1-9	10-Up
Gold Oxide





				Metric
				3.9	0.1535"	79	47.6	Spiral	Round	3.9	Split	2	NAS907 Type B	000000000	00000	00000

High-Speed Steel Short Length

Round Shank

Split

Our shortest high-speed steel bits, these are the most rigid for drilling the straightest holes. They're also good for tight spaces where longer bits can't fit. Also known as screw-machine and stub-length bits.

Black Oxide—The dark finish increases wear resistance and reduces friction to improve chip flow, so these bits can last 50% longer than uncoated bits.

Titanium Nitride (TiN) Coated—Drill at higher speeds and last longer than uncoated and oxide-coated bits, especially on tough materials like hardened steel and nickel.

Round Shank—The most common shank type. These fit in the chuck of drill presses and portable drills.

Split Point—Starts cutting on contact so you don’t need a pilot hole. The point also keeps the bit centered for straight and accurate holes, even with a portable drill.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes	Specs. Met		Each
Black Oxide





				Metric
				8.0	0.315"	79	20.9	Spiral	Round	8	Split	2	DIN 1897	00000000	00000
				8.1	0.3189"	79	37	Spiral	Round	8.1	Split	2	DIN 1897	000000000	0000
				8.4	0.3307"	79	37	Spiral	Round	8.4	Split	2	DIN 1897	000000000	0000
				8.5	0.3346"	79	20	Spiral	Round	8.5	Split	2	DIN 1897	00000000	0000

				Titanium Nitride (TiN) Coated





								Metric
								8.0	0.315"	79	38.1	Spiral	Round	8	Split	2	DIN 1897	0000000	0000
								8.5	0.3346"	79	38.1	Spiral	Round	8.5	Split	2	DIN 1897	0000000	00000

Cobalt Steel Jobbers' Length

Round Shank

Split

The toughness and wear resistance of cobalt steel in a length that's rigid enough for most applications. Cobalt lasts at least twice as long as high-speed steel. It can also run up to 25% faster at higher temperatures without damaging the bit on hard materials such as nickel.

Titanium Nitride (TiN) Coated—Drill at higher speeds and last longer than uncoated bits, especially on tough materials like hardened steel and nickel.

Uncoated—Polished to eject chips, these are also known as bright finish bits.

Round Shank—The most common shank type. These fit in the chuck of drill presses and portable drills.

Split Point—Starts cutting on contact so you don’t need a pilot hole. The point also keeps the bit centered for straight and accurate holes, even with a portable drill.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes	Specs. Met		Each
Titanium Nitride (TiN) Coated





				Metric
				4.5	0.1772"	79	47	Spiral	Round	4.5	Split	2	DIN 338	0000000	00000

				Uncoated





								Metric
								3.9	0.1535"	79	47.6	Spiral	Round	3.9	Split	2	NAS907 Type J	00000000	0000

Cobalt Steel Short Length

Round Shank

Split

Combine the toughness and wear resistance of cobalt steel with a short length for drilling the straightest holes. These last twice as long as high-speed steel and can run up to 25% faster at higher temperatures without damaging the bit on hard metals like nickel. Also known as screw-machine and stub-length bits, they fit in tight spaces where longer bits can't.

Titanium Nitride (TiN) Coated—Drill at higher speeds and last longer than uncoated bits, especially on tough materials like hardened steel and nickel.

Uncoated—Polished to eject chips, these are also known as bright finish bits.

Round Shank—The most common shank type. These fit in the chuck of drill presses and portable drills.

Split Point—Starts cutting on contact so you don’t need a pilot hole. The point also keeps the bit centered for straight and accurate holes, even with a portable drill.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes	Specs. Met		Each
Titanium Nitride (TiN) Coated





				Metric
				8.0	0.315"	79	21.1	Spiral	Round	8	Split	2	DIN 1897	00000000	000000
				8.5	0.3346"	79	20.1	Spiral	Round	8.5	Split	2	DIN 1897	00000000	00000

				Uncoated





								Metric
								8.0	0.315"	79	21.1	Spiral	Round	8	Split	2	DIN 1897	00000000	00000
								8.5	0.3346"	79	20.1	Spiral	Round	8.5	Split	2	DIN 1897	00000000	00000

Carbide-Tipped Steel Jobbers' Length

Round Shank

Standard

The performance of solid carbide but at a lower price point. These jobbers' bits have the balance of rigidity and length needed for most applications. Like carbide bits, they are stronger than cobalt and high-speed steel and maintain their sharp edges when drilling abrasive material. However, when drilling tough metals like iron and hardened steel, upgrade to carbide for longer life.

Round Shank—The most common shank type. These fit in the chuck of drill presses and portable drills.

Standard Point—Good for general purpose drilling. You’ll need to make a pilot hole to center the bit.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes		Each
Uncoated Carbide Tipped





				Metric
				3.3	0.13"	79	41.9	Spiral	Round	3.3	Standard	2	00000000	000000
				3.5	0.1378"	79	41.9	Spiral	Round	3.5	Standard	2	00000000	00000
				4.0	0.1575"	79	41.9	Spiral	Round	4	Standard	2	00000000	00000

Carbide-Tipped Steel Short Length

Round Shank

Standard

Our shortest and most rigid bits, these offer the performance of solid carbide at a lower price point. Like carbide bits, they are stronger than cobalt and high-speed steel to maintain their sharp edges when drilling abrasive material. However, when drilling tough metals like cast iron and hardened steel, upgrade to carbide for longer life.

Round Shank—The most common shank type. These fit in the chuck of drill presses and portable drills.

Standard Point—Good for general purpose drilling. You’ll need to make a pilot hole to center the bit.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes		Each
Uncoated Carbide Tipped





				Metric
				9.0	0.3543"	79	27	Spiral	Round	9	Standard	2	000000000	000000
				9.5	0.374"	79	28.5	Spiral	Round	9.5	Standard	2	000000000	00000

Chip-Clearing Drill Bits

With flutes that lift chips out of the hole, you don't have to stop drilling to clear these bits manually. The flutes improve coolant flow to dissipate heat and prevent clogs that can damage the bit and ruin the hole.

Cobalt Steel Jobbers' Length

Parabolic Flute

Split

Uncoated—Polished to eject chips, these are also known as bright finish bits.

Parabolic Flute—A U-shaped groove on the flutes cuts faster and clears chips more quickly than high-helix bits, so these are better for drilling deep holes.

Round Shank—The most common shank type. These fit in the chuck of drill presses and portable drills.

Split Point—Starts cutting on contact so you don’t need a pilot hole. The point also keeps the bit centered for straight and accurate holes, even with a portable drill.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes	Specs. Met		Each
Uncoated





				Metric
				4.5	0.1772"	79	47	Parabolic	Round	4.5	Split	2	DIN 338	0000000	00000

Hole-Starting Drill Bits

Create an accurate starting place in your workpiece. Cut an indent with these bits, then continue drilling with a longer bit. The indent prevents slipping so the final hole is centered and precise. Also known as spotting drill bits.

Cobalt Steel Short Length

Spiral Flute

Round Shank

Standard

Uncoated—Polished to eject chips, these are also known as bright finish bits.

90° Point Angle—Chamfers holes that will be followed by a smaller drill bit size.

Round Shank—The most common shank type. These fit in the chuck of drill presses and portable drills.

Standard Point—Perform best in stationary tools, such as a drill press.

						Shank				90° Point Angle
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes		Each
Uncoated


		8.0	0.315"	79	25.4	Spiral	Round	8	Standard	2	00000000	000000

Coolant-Fed Drill Bits

Channel coolant through the holes to reduce heat and evacuate chips more efficiently than other bits. These are designed for CNC machines that supply coolant through the spindle rather than an external source, such as a hose and nozzle. Coolant flows directly from the bit's tip onto the drilling surface. This speeds up cuts and leads to excellent performance in deep holes and tough materials such as stainless steel and titanium.

Carbide Maintenance Length

Spiral Flute

Shorter and more rigid than jobbers' length, these carbide bits are the hardest and most wear resistant you can buy. They stay sharp at high temperatures and faster speeds for the best performance on hard and difficult-to-machine materials. Also known as mechanics' bits.

Titanium Aluminum Nitride (TiAlN) Coated—No drill bits last longer. These are the best for high-speed, high-temperature drilling of very hard and abrasive materials, including titanium and fiberglass.

Round Shank—The most common shank type fits in a drill press chuck.

Four-Facet Point—The most accurate point style, it centers the bit without a pilot hole and keeps the bit stable while drilling hard metals.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	No. of Flutes		Each
Titanium Aluminum Nitride (TiAlN) Coated





				Metric
				7.0	0.2756"	79	34	Spiral	Round	8	Four Facet	2	00000000	000000
				7.5	0.2953"	79	40.9	Spiral	Round	8	Four Facet	2	00000000	00000
				8.0	0.315"	79	40.9	Spiral	Round	8	Four Facet	2	00000000	00000

Step Drill Bits

Drill multiple hole sizes using only one bit. These have steps with progressively larger diameters—the deeper they drill, the bigger the hole. Count the steps as you drill to achieve the proper size. These bits also deburr as they cut, so they're good for thin materials like sheet metal and plastic panels.

High-Speed Steel

Hex Shank

Standard

Wear and heat resistant, these bits are versatile for use on a range of materials.

Titanium Nitride (TiN) Coated—Drill at higher speeds and last longer than uncoated and oxide-coated bits. These are the best choice for hard-to-machine metals like stainless steel.

Uncoated—The most economical option, uncoated bits perform best when used on low-carbon steel and aluminum. Polished to reduce friction, they're also known as bright finish bits.

Hex Shank—Use with portable drills and drivers.

Standard Point—Good for general purpose drilling. You’ll need to make a pilot hole to center the bit.

					Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	For Max. Material Thk., mm	Type	Size, mm	Drill Bit Point Type		Each
Titanium Nitride (TiN) Coated





				Metric
				5.0, 7.5, 10.0, 13.0, 16.0, 19.0, 21.0, 23.0, 26.0, 29.0, 31.0, 33.0, 35.0	0.1968", 0.2953", 0.3937", 0.5118", 0.6299", 0.748", 0.8268", 0.9055", 1.0236", 1.1417", 1.2205", 1.2992", 1.378"	79	4	Hex	11.1	Standard	00000000	0000000

				Uncoated





								Metric
								5.0, 7.5, 10.0, 13.0, 16.0, 19.0, 21.0, 23.0, 26.0, 29.0, 31.0, 33.0, 35.0	0.1968", 0.2953", 0.3937", 0.5118", 0.6299", 0.748", 0.8268", 0.9055", 1.0236", 1.1417", 1.2205", 1.2992", 1.378"	79	4	Hex	11.1	Standard	00000000	00000