The best tap and die set can repair threads — SAE or metric. This can be a godsend. I would drill the bolt out, tap the hole, and cut new threads.
Example: I was a teenaged kid who had a tendency to break bolts when working on my cars. One memorable one included the nut and bolt that holds the steering wheel on a Chrysler 300M. The nut and bolt needed repair.
Best selling tap and die sets on Amazon
- CUT AND RENEW THREADS: The ABN Metric and SAE Standard Tap and Die 60-Piece Rethread Set Rethreading Kit for Cutting External and Internal Threads is a comprehensive set for cutting and renewing external and internal threads to exact standards
- BUILT TO LAST: Constructed from hardened alloy steel for maximum strength and longevity; Can cut materials such as cast iron, steel, aluminum, copper
- EASY STORAGE: Heavy-duty plastic blow-molded carrying case for easy transportation, safe storage, and quick organization
- CONTENTS: Package includes coarse and fine threads numbered taps and dies from #4-40 to #12-24 and fractional taps and dies from 1/4"-28 to 1/2"-20, 1/8"-27 NPT tap and die, metric tap and dies from M3x0.5 to M12x1.75, thread gauge, tap handle, die handle, small tap chuck, and a carrying case for your convenience
- SIZES: Metric taps 3x0.5, 4x0.7, 5x0.8, 6x1.0, 7x1.0, 8x1.25, 9x1.25, 10x1.0, 10x1.5, 12x1.75; UNC taps 4-40, 6-32, 8-32, 10-24, 12-24, 1/4, 5/16, 3/8, 7/16, 1/2; UNF taps 10-32, 1/4, 5/16, 3/8, 7/16, 1/2; Metric dies 3x0.5, 4x0.7, 5x0.8, 6x1.0, 7x1.0, 8x1.25, 9x1.25, 10x1.0, 10x1.5, 12x1.75; UNC dies 4-40, 6-32, 8-32, 10-24, 12-24, 1/4, 5/16, 3/8, 7/16, 1/2; UNF dies 10-32, 1/4, 5/16, 3/8, 7/16, 1/2; NPT tap 1/8-27; NPT die 1/8-27; Tap wrench M4-M12 3/16-1/2"; T-type tap wrench M3-M16 1/16-1/4"
- PREMIUM MATERIAL AND DURABILITY: Industrial grade GCr15 bearing steel construction ensures durability and tool longevity
- EXCELLENT CUTTING PERFORMANCE: All cutting teeth are precisely CNC machined and accurately heat treated to Rockwell hardness 60 HRC for best threading performance
- TAPERED TEETH DESIGN: Tapered coarse and fine taps and dies start threading more easily and smoothly, and prevent overthreading
- ALL-INCLUDED SET: This kit comes with a full range of most popular SAE taps & dies with both coarse and fine sizes, plus all needed wrenches, handles, a gauge and a storage case
- VERSATILITY AND WIDE APPLICATION: Perfect to create new threads or repair damaged threads on most metals like carbon steel, cast iron, aluminum, brass, copper and stainless steel
- Complete set of ratcheting T handle system of tap and die tools and 48 each taps and 48 each dies
- Taps and dies made from top quality carbon tool steel
- Blow molded case for safe and organized storage
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Let’s understand what a good tap and die set does.
What’s it all about?
A tap is a threaded tool designed for cutting or repairing threads on inner side of an already existing hole, thus creating female threads that hold a nut in metallic or other solid materials. The process is called tapping.
A die is the accompanying threading tool for making threads on a fresh bolt or for repairing threads of damaged male screw or bolt. The process is known as threading.
Usually, machines do the work, but manual dies and taps are used when things go wrong — i.e., a bolt head broke off.
These tools make a excellent addition if you do minor repairs of your car, boat or motorcycle at home.
Well-made set worth the money
The best way to determine if a set is worth your while is to examine the price. You may find that the best tap and die set under $50 does not suit your needs.
Brands like Morse, OSG, Greenfield and Butterfield, though expensive, offer high speed steel (HSS) taps and dies which are of high quality and perform well.
Rather than invest a truckload of money into a brand new set, you can also try locating a used set for sale.
Pawn shops, estate sales, auctions and Ebay are great places to start. You can even ask any retired machinists you know if they are willing to sell you their used sets at a substantial discount.
However, sometimes a full set of brand name HSS taps and dies can be hard to find.
If that is the case for you, you should try starting out with an inexpensive foreign brand, or any carbon steel set, and gradually replace the taps and dies that you use the most with premium HSS tools.
Keep a look out for the single-sized boxes of three HSS taps which are usually inexpensive in common sizes.
High speed steel or carbon steel?
While experts agree that HSS is a better quality metal than carbon steel, you should only buy the specific tap and die set that you need to get your work done.
Heavier HSS tools are important in industrial settings, but carbon steel works just as well for custom cutting for repairs around your home.
As a rule, carbon steel taps and dies are typically sufficient for chasing threads rather than cutting them.
HSS taps and dies are better for cutting most of the time because they stay sharper longer and use less force.
However, since they are expensive, a good set of Hanson/Irwin, Ace or Craftsman/Sears carbon steel taps and dies should work in a pinch if you don’t have an HSS tap or die in the size you need.
How do you handle handles?
If the tap and die process is new to you, an improper handle can lead to mistakes.
For example, ratcheting handles add torque, apply excessive force and have been known to strip threads or break taps and dies.
Smaller handles are better for beginning threaders because they prevent over-torquing and help the beginner learn the process.
However, ratcheting handles are great for experienced threaders.
They save you the extra step of having to reposition your hands every fraction of a turn and they turn strongly without any wiggling.
But, if you find a high-quality used set of taps and dies with handles that are worn or inappropriate for a job, they can always be replaced.
You should never turn down a bargain on brand name HSS pieces because of broken handles that can easily be switched out.
SAE and metric sizes
Tap and die sets are found in two different size standards, metric and SAE. SAE sizes such as halves, quarters and eighths are still used frequently in the United States, so any set that does not feature these denominations is not worth your money if you live that country.
Once you buy a set of taps and dies that includes all of the most common sizes in both SAE and metric, you be able to cut threads with near-perfect precision.
After all, when it comes to threading, “close enough” is simply not an option. That is why quality tool sets must include a wide range of taps and dies to meet the requirements of all jobs.
A sturdy plastic case will keep all your taps and dies organized and immediately available to you.
It will also save you time once you get used to the locations of the pieces that you use the most. A good case should have a clean layout so you can easily locate each tap or die quickly.
Another reason a good carrying case is crucial is that the pieces will stay in their marked positions instead of falling out and getting misplaced upon travel.
This is especially important if you buy a set of taps and dies with the sizes printed on them rather than etched into them, since those sizes will eventually wear off.
If you have a few loose taps or dies that do not fit in your carrying case, you still should not toss them in a drawer carelessly.
You can easily craft a wooden storage rack for the taps and a wooden peg rack to stack the dies. Leaving taps and dies sitting in a drawer can lead to the tools becoming dull, damaged or rusted.