Carbide taps have a lot of advantages, especially when you’re cutting very abrasive materials. The absolute best choice for tapping glass-filled polycarbonates, space age alloys, nonferrous materials, cast iron, and a range of other exotic materials, their anti-friction qualities lead to a longer tool life.

S.T.I. (Screw Thread Insert) Taps are special taps for helical coil wire screw thread inserts, which provide positive means for protecting and strengthening tapped threads in any material.
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Typically used on softer abrasive materials, these taps create more accurate thread forms than other standard taps. When you need to be precise, these carbide taps are the best choice.

North American Tool's  STI taps are correctly sized to produce an internal thread that accommodates a helical coil wire screw thread insert. The insert, in turn, will accept a screw thread of the nominal size and pitch at final assembly. Screw thread inserts provide stronger tapped threads (stronger assemblies) due to a more balanced distribution of loads throughout the length of thread engagement.

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Thread forming taps (Tru-Flo taps) offer improved thread quality and strength due to the fluteless design, and therefore allows for greater fastener strength in the threaded product. This tap does not cut, so it is “chipless,” and therefore will not cause a chip problem.  This is why thread forming, over thread cutting, eliminates costly and time-consuming chip clean-up and disposal.

Thread forming taps are fluteless and include lubrication grooves. Not intended for general applications, they work by displacing the metal without removing it. Because of this, they are ideal for chip removal in blind holes.

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​Tru-Flo Thread Forming Taps Features 

• Improved thread quality and strength due to fluteless design of tap; allows greater fastener strength in threaded product.
• Tapping speeds can be increased as much as double that of conventional cutting taps…more tapped holes per hour.
• Thread forming (over thread cutting) eliminates costly and time-consuming chip clean-up and disposal.
• Improved tap life, even in abrasive materials…no cutting edges to get dull.
• Lubrication grooves allow forced passage of air and lubricant when tapping.
• Simplifies tapping of problematic blind bottoming holes where adequate chip clearance is impossible with chip-producing cutting taps.

A cost-efficient solution, only the cutting portion of insert taps is made from carbide. Their HSS body is able to absorb vibration and account for their lack of rigidity.

If you’re considering testing the waters with carbide taps, insert taps are a great option. It's a very economical way to utilize the benefits of carbide with solid carbide cutting face inserts meticulously brazed to a H.S.S. tap body.
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Carbide Insert Tap Features

• High speed steel body absorbs excessive shock and offers the rigidity necessary to minimize carbide breakage or chipping.
• Ideal for high production runs, offering the capability to achieve higher speeds and feeds, with fewer tool changes.
• High performance tapping allows greater efficiencies in part throughput.
• Can also be used in conjunction with surface treatments for enhanced performance.
• Carb-I-Sert® Taps are available in a wide range of sizes (inch and metric) in both straight and taper pipe threads.

Highly abrasive materials like cast iron, polymers, glass filled polycarbonates, and some cast aluminum are called “hard” materials for a reason. They’re hard to machine, hard on tool life and hard on production cycle times.

​How do you overcome the difficulties of making parts out of challenging raw stock? By using a tool that’s even tougher. Consider a change from steel taps to carbide taps.

​We offer carbide taps in UN and Metric sizes as well as straight and NPT/F Pipe and STI Standards. A wide range of styles and features are available, including straight flute, spiral flute, spiral point, and forming taps. For increased performance and life, we can customize tools with a full line of surface coatings such as TiN, TiCN, and TiALN.

Machining with carbide does come with some “do’s and don’t”. Hand­ tapping is generally not recommended. Rigid tapping and spot­-on alignment are critical to avoid breakage. Not to worry, however. Modern CNC equipment is ideally suited for carbide applications.

Here’s some additional tips. Coolant holes through the taps are an option for flushing chips out of the holes on the most difficult materials like some of the tougher stainless steels and space-­age alloys. Carbide STI (Screw Thread Insert) tapping of these materials has become commonplace in the aeronautical and aerospace industries.

Although initially more expensive than HSS taps, significant savings can be realized, especially in long-­run jobs. Higher cutting speeds, greater tool life, and reduced down­time from fewer tooling changes translate into reduced machining costs.

An alternative to costly larger sizes is our line of Carb­I­Sert® Taps. Solid carbide cutting surfaces are bonded onto a high-speed steel body to provide the best of both worlds; durability of carbide with the “forgiveness” of a steel body and shank.

So, don’t let difficult materials give you a “hard” time. Contact us anytime and put our carbide taps to work for you.

Watch for Part 2 of this series on carbide taps!
​Coming in August 2021: The Different Types of Carbide Taps and When to Use Them

Almost a year ago, Allen Benjamin, which has been a part of North American Tool,  was purchased by GWS Tool Group. GWS Tool Group is a US-based, vertically integrated manufacturer of highly engineered custom, standard, and modified standard cutting tools, primarily servicing the aerospace and defense, power generation, automotive and medical sectors. GWS Tool Group has acquired multiple businesses in the course of its growth which now serves as the respective manufacturing divisions for the Company.  

Just because there is a new owner, doesn't mean that the quality of an Allen Benjamin Tap has changed! 

If you’re in the market for high tensile strength carbide taps and metric taps, we can assure you that you’re in the right place. Not only is Allen Benjamin a leading supplier of the industry’s most durable, longest lasting carbide taps, we offer our customers the convenience of ordering online. In this day and age, we believe that quick access and top-notch customer services are critical.

In today’s post, we’re going to look at why it is beneficial to order your carbide taps from Allen Benjamin.

Quality
Allen Benjamin carbide taps are highly efficient when tapping abrasive metals such as aluminum, non-ferrous metals, and exotic materials. With a much higher tensile strength than standard taps, their high-quality carbide taps can withstand the rigorous demands of your application.

Selection
Allen Benjamin offers a staggering range      of carbide taps, metric taps, HSSE taps, tapping fluid, extensions, and more. If it’s taps that you are looking for, you can be confident that they’ve got them and have them ready for delivery.

Service
Allen Benjamin guarantees that all of their products will be the absolute best quality, within standard tolerances and dimensions, and consistent with application specifications. If their goods don’t meet your needs, you can contact us for a return authorization.

At Allen Benjamin, they take pride in offering the industry’s best taps. But, more importantly, they aim to provide our customers with access to a simpler, faster way to order their operation’s critical parts, supplies, and components.

If you’ve been searching for a supplier that will meet your needs and rise to meet your challenges contact us today!

How can you optimize a tap's chamfer based on your application?

Although North American Tool/ GWS  stocks many common special taps with standard chamfer lengths, they can design and manufacture a special tap for your application.

​Optimizing the chamfer results in, longer tap life, reduced tapping torque, better finish, and make the difference between success and failure.

As most of you know, the chamfer is the tapered section on the front of the tap. It includes the length, angle, radial relief, and point diameter.

​As the tap rotates and advances forward, each succeeding chamfered tooth enters the drilled hole and takes deeper and deeper cuts until the first full thread on the tap completes producing a full thread in the part. The balance of the tap’s threads within the length beyond the chamfer, do not do any cutting and just goes for the ride.
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Increasing the total number of chamfered teeth cutting, can increase tap life exponentially.

​The example above shows that a standard plug chamfer (3 to 5 threads) length, so on a 4 fluted tap, it will range between 12 to 20 cutting teeth. Because North American Tool/ GWS understands more is better, they make it a point to manufacture our taps with a chamfer length closer to maximum length, in this case, 5 threads. This is also true for the other standard chamfer lengths Bottom, Semi Bottom, and Taper. 

Although more is better, you may be limited to the length of chamfer due to the job requirements. We should also note that the incomplete threads created and left in the part by the chamfer are not too full thread height and will cause assembly interference, therefore they are not considered part of the required thread length.

As for manufactured specials, knowing your application requirements is necessary for us to design a tap that optimizes performance. For chamfer design, North American Tool/ GWS would need to know, tap drill size, tap drill depth, and full thread length requirement.

Knowing the tap drill size allows us to grind a chamfer with a point diameter that permits the tap to start cutting within the first half thread of entry. Because there are many factors that go into determining a tap drill size, there can be a relatively wide range of diameters. If the chamfer point diameter is smaller than the tap drill diameter, then the tap may not start cutting until the second chamfer tooth or beyond.

Using the same 4 flute, plug tap from the example above, in an application with a tap drill size larger than the chamfer point diameter, such that the tap does not start cutting till the 2nd chamfer tooth, will have a reduction in cutting teeth by 6 (1.5 threads X 4 flutes), or 30%. If the application is such that only a bottom chamfer (1 to 2 threads) can be used, and it is ground to the maximum length of 2 threads it will result in a reduction of cutting teeth from 8 (2 threads X 4 flutes) to 6 (1.5 threads X 4 flutes) or 75%.

Knowing the tap drill depth and full thread length requirement also allows us to design the maximum length chamfer for your application. This may take into consideration the overspin of the machine spindle, or room at the bottom of a blind hole so the tap does not run into any chips that may have made their way to the bottom.

Although the information presented may be confusing, hopefully we have explained the importance of the chamfer, and the many considerations that go into its proper design.

So, if you are ready to increase tap life, reduced tapping torque, improve the finish, and make the difference between success and failure, give us a call with your application requirements.

If you’re cutting extremely abrasive material, we’re confident that you’ve already investigated the benefits of carbide taps. Whether you’re tapping cast aluminum, nonferrous materials, polymers, cast iron, or any number of other materials, carbide taps offer better edge wear resistance and, more importantly, help to reduce downtime and increase profitability.

As an ISO 9001:2008 registered manufacturer, Allen Benjamin is absolutely committed to offering the best taps on the market. In today’s post, we’re going to look at a few of the benefits of using our carbide and high-performance taps.

Stronger
Ideal for very abrasive metals, carbide taps have a much higher tensile strength than standard taps. Because of this, they offer a longer tool life and work to reduce production costs.

Better performance
Due to their ability to increase tool life, carbide taps have a positive effect on your operation’s performance. Helping you to reduce maintenance and – by extension – downtime, they allow your staff to focus on more productive, more profitable tasks.

Cost-effective
While the initial cost may be higher than standard taps, carbide taps are far more cost-efficient in the long run. Their extended tool life results in fewer replacements which, of course, leads to less reorders and money saved over time.

At Allen Benjamin, we are steadfastly dedicated to our customers’ productivity. Always aiming to offer products that are capable of reducing maintenance, increasing uptime, and improving profitability, we strive to act as a convenient, responsive supplier of high-quality carbide taps. Whether you’re a small, local manufacturer in need of a handful of taps or a large, multi-national operation looking to place a large order, you can be confident that we can help. If you have any questions about our products, we encourage you to reach out to us today to discuss your needs!

Allen Benjamin’s carbide taps provide a substantial increase in performance and tool life over HSS – or high speed steel – taps. As a result, our customers experience longer tool life and, due to this, reduced production costs that help to contribute to higher profits and a more efficient line.

Getting a good understanding of the definitions of the parts of a tap will help you to better understand the functions of  tap designs.  Special thanks to North American Tool for letting us share their short and simple explanations!

Have you ever had a tapping job that was so troublesome that it caused heartburn or acid indigestion due to broken taps, bad finish, short tap life, over or undersized threads, etc.?

One way of avoiding or alleviating such a condition is accomplished with the use of a tap feature called “relief”. The definition of “relief” according to Marian Webster, is removal or lightening of something oppressive, painful, or distressing. For a tap, “relief” is the reducing of surface contact between the tap/tap feature and the part being tapped. Surface contact generates unwanted heat causing the issues mentioned above. Depending on the tap feature, relief is applied in a direction that is, radially, around the tap, or axially, along the axis of the tap.

All taps require a minimum number of features to have relief for it to cut, other reliefs are applied when the tapping application requires it. There are always tradeoffs when designing a tap, if a relief is applied or it’s amount is greater than necessary, it can cause the tap to run free or loose to a point it will cause heartburn or acid indigestion by producing issues mentioned above.

Relieved features that are always necessary on a tap are:
               
Chamfer, the tapered threads at the front of the tap. The crests or major diameter of the chamfered threads are radially relieved from the cutting edge to the heel of the land. Without this relief it would be like cutting a tomato with the non-sharp side of a knife, you can imagine the results of that. When looking at a taps chamfer, relief results in the crest width being wider at the cutting edge and narrowing towards the heel;

Back Taper, a slight gradual reduction of the taps thread form including it’s major, pitch and minor diameters. It starts at the chamfered end of the tap and continues axially for the length of thread towards the shank end.

Additional features that can be relieved

Thread Relief, a radial reduction of the taps major and pitch diameters from the cutting edge to the heel. Relieving of the pitch diameter results in the minor diameter being relieved as well due to the manufacturing process whereas the major diameter is relieved separately. The application of the major or pitch diameter relief is normally applied separately but both can be done in combination. Relief of pitch diameter is the most common followed by the major diameter. Thread relief is applied when Back Taper alone is not enough to prevent surface contact when tapping materials that close in and squeezes the tap like stainless steel. The rate of reduction from the cutting edge to the heel is based on the material being tapped and, in some cases, the tapping application.

There are two common types of Thread Reliefs:

• Eccentric, a radial relief in the thread form starting at the cutting edge and continuing to the heel.
  
• Con-Eccentric, Radial relief in the thread form starting back of a concentric margin.

The reliefs we have discussed so far are applied during the tap manufacturing and other than the chamfer relief cannot be added or changed. If you are in a bind and must ship parts but can’t wait for us to design, manufacture and ship the appropriate tap, there are additional types of relief that can be applied that may work in a pinch. Sometimes referred to as a poor man’s relief, something you may be capable of doing in your shop without too much trouble to get you through a quick job, or until properly designed tools arrive.

The application of relief types and amounts are dependent on many factors such as material properties being tapped, style and size of tap, how the tap is being used (hand, machine, etc.) and application requirements, etc. By providing us with as much information about your tapping application, it will enable our engineers to design a tap with the proper relief. This will help alleviate troublesome heartburn or acid indigestion.

First things first, what is the root of a tap?

The root of a tap is the surface at the bottom of the thread-form that connects adjacent thread flanks and is expressed as a width or as a diameter. The term root diameter is also called minor diameter, it’s one of those things, you say rain and I say precipitation, meaning the same thing...

Recently we had an application question at North American Tool.   A customer had opened up the drilled hole to 55 percent of thread in hopes of reducing wear and increasing tool life.  Instead, it lead to the cut tap breaking at the first full thread of engagement.  That prompted a engineering discussion and is the basis of this technical article to address this very common misperception.

If a tap doesn’t create the hole, why is the hole size so important?

This leaves the good machinist to select a drill that is more or less than 75%.  If 75% is good, then a higher number is better, right?  WRONG (in many cases).  On page 115 of the current North American Tool catalog a range for percentage of threads from 50% to 85%, with the recommended range between 65% and 75%.  This guideline range to use is a reflection of several factors:

1. The higher the percentage of thread, the greater the stress factors on the tap and the greater the likelihood of failure.  Excessive torque can lead to catastrophic failure, with broken pieces of tap or galling in the thread form.
2. A lower percentage of thread still provides the same pitch diameter, which is the only point the flanks of a fastener contact with the threads that have been tapped. They still provide the same pull out torque.
3. Too low of a percentage of thread can lead to cross threading when engaged with the fastener.

In higher tensile steels, larger hole sizes (less percentage of thread) may work better to reduce torque in tapping. When using oversize hole diameters, the tap should also have an oversize chamfer point diameter so all threads in chamfer are cutting and not just dropping in a hole.

Such was the case with the application porblem. As was stated above the operator thought that by increasing the drill diameter size would lead to better tool life. Instead, because the diameter was of the hole was so large the cut tap did not engage the threads along the chamfer length and instead engaged at the first full thread at the end of the chamfer.  The caused premature wear and stress on the that thread in the flutes and eventually to catastrophic failure.  The solution was a modified tap from North American Tool.

At the end of the day, taps are made to very strict tolerances, often much more so than the piece parts they are called on to machine, and the first place one might want to find blame is with the tap. 

Why?
Because;

1. the tap is easily replaced with another one and 
2. it is the least expensive component of possible issues with an application.

What if one manufacturer makes a tap that works and another one made by a different company doesn’t work at all? 

In all likelihood, the “general purpose” of one is closer to the correct geometry for the application.  One might get a completely different result if another material were being machined. Therefore it is always best to order a tap for the specific application.