7/8"-9 Dies | McMaster-Carr

Plug Chamfer—Plug-chamfer taps are a versatile choice for most tapping applications. With 3-5 chamfered cutting threads, they require moderate torque and are often used for start-to-finish tapping of through holes and closed-end holes. However, they do not start threads as easily as taper-chamfer taps. When using them to tap closed-end holes, be sure to leave sufficient space at the bottom for chips to accumulate.

Taper Chamfer—Taper-chamfer taps have 7-10 chamfered threads at the tip for cutting into the workpiece. They require less torque than other chamfer types, making them a good choice for starting threads and tapping through holes. However, a longer taper means that they cannot thread as close to the bottom of closed-end holes.

Hex—Hex-shaped dies are for thread repair and can be used with conventional wrenches.

	Die Shape	Die Sizes Included	Wd.	Container Type	Includes		Each
Carbon Steel Taps and Dies







	Right-Hand Thread

	65	4-40, 6-32, 8-32, 10-24, 10-32, 12-24, 1/8"-27, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, 9/16"-12, 9/16"-18, 5/8"-11, 5/8"-18, 3/4"-10, 3/4"-16, 7/8"-9, 7/8"-14, 1"-8, 1"-14, 1/4"-18	Plug, Taper	Hex	4-40, 6-32, 8-32, 10-24, 10-32, 12-24, 1/8"-27, 1/4"-18, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, 9/16"-12, 9/16"-18, 5/8"-11, 5/8"-18, 3/4"-10, 3/4"-16, 7/8"-14, 7/8"-9, 1"-8, 1"-14	5/8", 1", 1 7/16", 1 13/16"	Plastic Case	Die Wrench (4), Tap Wrench (4), Thread Gauge	00000000	0000000

Two-Piece Thread-Repairing Die Sets

Restore threads anywhere along the length of a bolt, stud, or rod with sets that include a wide variety of sizes. Since you clamp these dies into place, they're often used on extra-long fasteners or when you can't access the end of your workpiece. Dies smooth damage and clean threads so connections stay secure. Turn them with a hex die wrench or a standard adjustable wrench.

Black-Oxide Tool Steel—Hard and wear resistant for long life, these dies work well on both metal and plastic.

	Thread Size	Thread Type	Wd.	Container Type		Each
Black-Oxide Tool Steel



	20	1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, 9/16"-12, 9/16"-18, 5/8"-11, 5/8"-18, 3/4"-10, 3/4"-16, 7/8"-9, 7/8"-14, 1"-8, 1"-14	UNC, UNF	1", 1 3/8", 1 3/4"	Plastic Case	0000000	0000000

Thread-Repairing Die Sets

Be ready for repairs by keeping a range of die sizes on hand. These dies smooth out flaws and remove dirt and rust so threads make strong connections. Don’t risk damaging threads further with an inferior quality die. Our dies are machined in the U.S. to precise dimensions for a perfect thread profile. Turn with a hex die wrench or a standard adjustable wrench.

Uncoated Carbon Steel—Hard and wear resistant for a long life, these dies work well on both metal and plastic.

	Thread Size	Thread Type	Wd.	Container Type		Each
Uncoated Carbon Steel



	10	1/4"-20, 5/16"-18, 3/8"-16, 7/16"-14, 1/2"-13, 9/16"-12, 5/8"-11, 3/4"-10, 7/8"-9, 1"-8	UNC	19/32", 11/16", 25/32", 7/8", 1 1/16", 1 1/4", 1 7/16", 1 5/8", 1 13/16"	Plastic Case	000000	0000000


	20	1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, 9/16"-12, 9/16"-18, 5/8"-11, 5/8"-18, 3/4"-10, 3/4"-16, 7/8"-9, 7/8"-14, 1"-8, 1"-14	UNC, UNF	19/32", 11/16", 25/32", 7/8", 1 1/16", 1 1/4", 1 7/16", 1 5/8", 1 13/16"	Plastic Case	000000	000000

Thread-Repairing Die Nut Sets

The dies in these sets match the width of hex nuts that are the same thread size, so one tool can turn both. For tight spaces, use with a ratcheting wrench since it requires minimal clearance to turn. Repairing dies remove imperfections and rust so threads engage properly for a strong connection.

	Thread Size	Thread Type	Wd.	Container Type		Each
Uncoated Carbon Steel



	5	3/4"-10, 7/8"-9, 1"-8, 1 1/8"-7, 1 1/4"-7	UNC	1 1/16", 1 1/4", 1 1/2", 1 5/8", 1 3/4"	Plastic Pouch	0000000	000000

Thread-Repairing Dies

Rescue mangled threads and return them to like-new condition. By repairing threads, you don’t have to replace the fastener or resize holes. These dies smooth out flaws and remove rust so threads engage properly and connections stay strong. Turn them with a hex die wrench or a standard adjustable wrench.

Don’t risk damaging threads further with an inferior-quality die. Our dies are machined in the U.S. to precise dimensions for a perfect thread profile.

Uncoated Carbon Steel—Hard and wear resistant for a long life, these dies work well on both metal and plastic.

			Uncoated Carbon Steel
Thread Size	Thread Type	Wd.		Each
7/8"-9	UNC	1 5/8"	0000000	000000

Dies

Rotate these dies around studs and rods to create new fastener threads. A cut above lower-quality dies that can leave inferior threads, these are machined in the U.S. to precise dimensions for accuracy and consistency.

They are adjustable, so you can cut a shallow thread that makes it easier to get the die started on the first pass. Turn the set screw to open the die to its largest diameter. Then rotate the die with a round die wrench and adjust the screw as you make additional passes to reach the proper thread size.

Uncoated Carbon Steel—Our most economical dies, these are good for jobs that pop up. They work on most metal and plastic but will dull faster than high-speed steel dies.

Uncoated High-Speed Steel—The most versatile dies stay sharp and cut cleanly, even if you use them every day. They last much longer than carbon steel dies and you won’t have to work as hard to create threads.

Titanium Nitride (TiN)-Coated High-Speed Steel—When you regularly work on challenging metals like stainless steel, choose dies with a TiN coating that reduces friction and resists heat. They turn faster and last longer than uncoated dies.

	Dies								Die Wrenches
			Uncoated Carbon Steel		Uncoated High-Speed Steel		Titanium Nitride (TiN)-Coated High-Speed Steel
	Thread Size	Thread Type		Each		Each		Each		Each
2" OD



		7/8"-9	UNC	00000000	000000	0000000	000000	0000000	0000000	00000000	000000


		2 1/2" OD



				7/8"-9	UNC	00000000	000000	———	0	———	0	00000000	00000

Left-Hand Thread-Repairing Dies

Repair instead of replacing left-hand fasteners, which can be expensive and hard to find. These dies correct flaws and clean out rust so the threads engage properly. Don’t risk damaging threads further with an inferior quality die. Our dies are machined in the U.S. to precise dimensions for a perfect thread profile. Turn them with a hex die wrench or a standard adjustable wrench.

Uncoated Carbon Steel—Hard and wear resistant for a long life, these dies work well on both metal and plastic.

			Uncoated Carbon Steel
Thread Size	Thread Type	Wd.		Each
7/8"-9	UNC	1 5/8"	0000000	000000

Thread-Repairing Die Nuts

If your wrench can turn a hex nut, it can turn these dies. They match the width of nuts of the same thread size, so you only need one tool to remove the nut, repair threads on the fastener, and put the nut back on. When space is tight, use dies with a ratcheting wrench since it requires minimal clearance to turn. Repairing dies remove imperfections and rust, resulting in threads that engage properly for a strong connection.

			Uncoated Carbon Steel
Thread Size	Thread Type	Wd.		Each
7/8"-9	UNC	1 1/4"	00000000	00000

Ridgid Pipe Threader Dies for Thread Cutting

Use these dies with Ridgid pipe threader die heads on Ridgid pipe threaders.

				High-Speed Steel
	For Thread Size	For Pipe Threader Model No.	No. of Pieces		Each
For UNC Right-Hand Thread







				For Die Head Model Numbers 504A, 711, 811A, 815A, 816, 817

				7/8"-9	300, 535A	4	0000000	0000000