Tap and die sets may not be as well-known as common tools like screwdrivers or socket sets, but their specialized function can help with many different projects and repairs.
Taps are long cutting tools that broadly resemble drill bits. Along with a tap wrench, taps are used to cut threads into a hole within metal or wood. Dies are used to cut threads onto the exterior of a long, bolt-shaped piece of metal or wood, enabling the bolt to be used as a fastener. In short, taps cut the female threads and dies cut the male threads on a fastener pair.
The best tap and die set for you depends on how much you’ll use it, which materials you’ll be working with, and how many size options are required for your projects.
The specialized tap and die sets are designed to cut threads into wood, while most common tap and die sets are designed for use with metal. However, even some metalworking tap and die sets cannot be used on all metals if their construction material is weaker than the material they’re attempting to cut. So, quality is key.
Ahead, learn the basics of choosing a tap and die set, and don’t miss our roundup of top favorites among the best tap and die set options available.
- BEST OVERALL: GEARWRENCH 75 Piece Ratcheting Tap and Die Set
- BEST FOR PROS: Neiko 00916A SAE Pro-Grade Titanium Tap & Die Set
- BEST FOR WOOD: Kings Country Tool Tap and Die Set
What to Consider When Buying a Tap and Die Set
Before purchasing a new tap and die set and jumping into your next project, take a look at these factors to make sure you decide on the right set for your purposes.
Tap and die sets can range widely when it comes to the number of parts included. For instance, a specialized woodworking set may have only three pieces, while a more comprehensive metalworking set may have more than 100 pieces, especially if taps and dies in both metric and SAE measurements are included.
Versatility also refers to the variety of parts in a tap and die set. Taps come in three different types, including taper taps, plug taps, and finishing taps.
- Taper taps are used for initial threading because the end tapers to a smaller diameter that makes it easier to start a thread.
- Plug taps are the most common, as they are useful for both initial threading and finishing threads, though they are more difficult for initial threading than taper taps and cannot thread as fully as finishing taps.
- Finishing taps are the best option for finishing a thread pattern. They can cut completely to the bottom of the hole, allowing bolts to be threaded all the way down. Finishing taps are not for initial threading because they have a very small unthreaded end that makes it difficult to start cutting threads.
Dies also come in more than one type, including circular die, split circular die, and a die nut.
- Circular dies are the most commonly used type to cut threads into the exterior of bolts. These dies will be included in almost every set.
- Split circular dies can be split completely in half or have just a single split, which allows them to accept larger materials. These are for cutting shallow threads on the first pass, then deeper threads with each subsequent pass as the die is tightened around the bolt.
- Die nuts are a simple follow-up tool that sharpens existing threads but does not create new ones.
To properly use a tap and die set you will need to have at least one basic tap wrench and one basic die wrench, though a ratcheting tap and die set is ideal.
- A tap wrench looks like a long, thin bar with a rectangular opening and adjustable teeth that fasten around one end of the tap so it can be used to cut threads without slipping.
- A die wrench looks similar to a tap wrench, except that the opening in the middle is shaped to accept dies, which are then fastened to the wrench with one or more set screws.
- A ratcheting tap and die wrench takes some of the manual work out of the process. This style of wrench lets you cut clockwise, but will not loosen when you rotate the wrench counterclockwise unless it has been released, similar to a ratcheting socket wrench. The reason for this is so that you do not have to use a hand-over-hand clockwise cutting method that can quickly get tiring.
If you’re investing in a good-quality tap and die set, your tools should be protected. A strong, durable steel or plastic storage case is great to prevent rusting, corrosion, and impact damage when you’re storing or transporting the tap and die set.
Another important consideration for any storage case is how well it holds the pieces in place when closed. There are few things more frustrating than safely packing up your tap and die set in its case, only to find that all the pieces fall out of place when you pick up the case to move it.
When purchasing a tap and die set, material is an important consideration because only sets made with harder materials will be able to cut through the harder metals. Sets made with soft metals like aluminum are intended to be used with wood and cannot be used to cut threads into metal.
Tap and die sets made with moderately hard metals like alloy steel are great for most metals, but would struggle to effectively cut into harder materials like stainless steel. To be able to cut harder metals, you need a set made with carbon steel, high speed steel (HSS), titanium, or cobalt.
Tap and die sets are broken up into two common measurement systems: Metric and Society of Automotive Engineers (SAE).
Metric tap and die measurements are determined by measuring the distance between the thread crests in millimeters. The crest of a thread is the protruding part, regardless of whether it is internal or external. In contrast, the root is the groove that sits between the two flanks that connect the crest to the root.
SAE tap and die measurements are much easier to understand and are simply measured in threads per inch (TPI). To find this number, just hold a measuring tape up to the thread pattern and count how many complete threads are in an inch. Alternately, you could just use a pitch gauge if you have one or if one is included with your tap and die set. A pitch gauge is a specialized tool for determining SAE or metric tap and die measurements.
Tips for Buying and Using a Tap and Die Set
If you are just starting out, then a basic 20- or 40-piece tap and die set should be all you need. It will come with the most common sizes and types of taps and dies, which will allow you to complete most projects. However, if you have a specialized project or you know that you will need a certain type of tap or a specific die, then make sure that you get a set that includes the pieces that you need.
Another important factor to remember is that for most metals, the manufacturing process can make them very hard, but it also makes them brittle when they’re stressed on the wrong points. So when using the tap and die set, make sure to take the time to clear the metal and wood shavings after every full rotation to prevent the tools from breaking.
- Make sure that you buy a set that includes the types of taps and dies that you need.
- Invest in a tap and die set that can easily handle the materials you frequently use.
- Taps and dies are brittle, so always take your time to clear the excess metal or wood from the flute during thread cutting to prevent breaking the material or your tools.
Our Top Picks
These top-rated products are some of the best tap and die sets on the market. Based on your shopping considerations, choose the set that is compatible with your project.
This GEARWRENCH tap and die set eliminates the need for hand-over-hand turning, which can quickly fatigue hand muscles. Instead, a reversing lever allows you to drive the tap or die clockwise to cut the threads, then reverse the wrench handles counterclockwise to a better grip position before driving the tap or die in again.
The set is made of carbon steel and comes in a durable black storage case. It comes with 20 dies and 48 taps, including circular dies, taper taps, and plug taps, in both metric and SAE standard sizes.
The 75-piece set also has a metric thread gauge and SAE thread gauge, as well as die adapters that work on round- or hex-shaped dies. A twist lock guide system keeps the parts fastened to the handle during use, allowing you to produce neat and straight threads.
This is an excellent choice for professionals seeking a durable, high-quality tap and die set that can be used with a range of materials. There are 20 circular dies in all, with 10 being coarse (UNC) dies and 10 being fine (UNF) dies. Each die’s size is engraved on its side.
The tapering taps are similarly divided between 10 UNC and 10 UNF profiles, so you can choose the appropriate thread designation for your project.
The Neiko set’s carbon steel construction boasts titanium cutting edges to keep the taps and dies sharp for up to 20 times longer than alloy steel. The heavy-duty plastic case also helps protect the tools from rust and corrosion.
The set also includes two tap wrenches, a die wrench, a screwdriver, and a thread pitch gauge with either SAE or metric measurements.
If you need a tap and die set for woodworking, check out this Kings County Tools set, specially designed for cutting threads into hardwood.
The set comes comes with a two-handled thread box that contains the die, a plug tap, and a finishing tap. This thread box is made of solid hardwood and features a steel die that cuts through wood with ease. The taps are made with hardened steel.
This tap and die set does not come with a carrying case, but with only three pieces, you may be fine storing it in your toolbox or tool chest.
FAQs About Your New Tap and Die Set
Take a look at the answers to these common questions about tap and die sets.
Q. How do you use a tap and die set?
To use taps, place the tap in a tap wrench and line it up with the hole that needs threads. Turn clockwise one turn, then counterclockwise half a turn to release the metal chips produced by the first turn so that your tap doesn’t break. Repeat until the threads are fully cut.
To use dies, secure the unthreaded bolt in a vice, then place the die on the end of the bolt that you want threaded. Begin cutting the threads with the same alternating clockwise and counterclockwise pattern as was used with the taps. Continue until you have cut threads as far down the bolt as you want.
Q. Can you use a tap and die set on wood?
Tap and die sets that are intended for cutting metal should not be used on wood. However, sets that are designed to be used on wood, like the Kings County Tools Tap and Die Set, make quick work of cutting threads in wooden holes or making wooden bolts.
Q. What is the best material for a tap and die set?
The material you use should be based on the material you’ll be cutting. High-speed steel (HSS) is the most commonly used material, because it can be used to cut most metals used in tap and die applications. Cobalt or titanium may also be used for very hard materials like stainless steel.