Part Four: The Screw Thread Solution

So far in Fixing Fasteners, we’ve provided a short introduction to screw threads and threaded fasteners, along with some options for making them stay put. Part Three described one of the most efficient systems for accomplishing this, the Detroit Tool Company's wedge ramp thread design. The patent for that simple yet ingenious invention has long since run out and is now represented by two companies—Stanley Engineered Products with its Spiralock^TM brand and its alternative, Emuge-Franken’s Self-Lock™ thread locking technology.

Part Three: A Valiant Attempt

In the previous two segments of Fixing Fasteners, we reviewed the basics of thread design and provided some brief descriptions of the industry's various attempts to secure fasteners. This section will discuss a more practical approach to the latter. In 1979, the Detroit Tool Company made a simple modification to a standard thread profile. They called it Spiralock^TM, and it soon became quite popular for use in mission-critical applications by military and aerospace manufacturers, and eventually the medical industry.

Part Two: As the Screw Turns

In Part One of Fixing Fasteners, we offered a brief overview of screws and thread manufacturing, their different classes of fit, and some comments on the importance of proper tolerancing and gaging when machining screw threads. Adhering to these guidelines is the first step toward making strong, dependable fasteners. However, even the highest quality screw, nut, or bolt can come loose unexpectedly (often at the worst possible time) when subjected to vibration and other forces.

That's because threaded fasteners are intended to come apart. It’s an unfortunate truth (or a fortunate one, depending on your perspective) that all machinery and other mechanical assemblies must be constructed in a manner that allows them to be serviced, refilled, and repaired. If not, they could simply be welded together, eliminating the need for threads entirely.

Part One: Threads on Parade

This four-part series will discuss threaded fasteners, why they come loose, and how engineers and product designers can prevent this unfortunate, sometimes dangerous event. We’ll preface it by saying that Emuge-Franken is a cutting tool manufacturer with more than a century of experience in this area. The company invented the first spiral point tap for producing internal threads in 1921 and has since developed some of the highest-quality drills, end mills, and threading products on the market. As you’ll soon see, they have also addressed the problem just mentioned—fasteners coming loose—with a comprehensive and innovative solution.

Although EMUGE is known for its high-quality line of tapping products, there are times when thread milling is a better choice. In this post, we’ll explore a few of the key differences between the two, and when to use one over the other.

For those engaged in high-mix, low-volume machining, versatility (mostly) rules

Aluminum one day, titanium the next, low-carbon steel the day after that. When you have no idea what’s coming down the pike, it's obvious that you need cutting tools able to survive whatever you throw their way. But is survival enough? Is it better to sacrifice some modicum of performance to avoid switching to a material-specific cutting tool, or to keep the tool crib inventory to the bare minimum by going to a more general-purpose grade of carbide and tool geometry?

In PartOne of this article, I presented some reasons why shops should consider material-specific taps. This section will explore some of the features to look for in one. Before diving in, however, it’s essential to recognize the difference between plug and bottoming taps.

Drilling has long been recognized as one of the most common yet most challenging of all metalworking operations. Tapping is even tougher. Aside from problems with chip evacuation and potential coolant starvation, there's the sheer amount of metal being removed relative to the available space for the cutting tool.

Hundreds of New Products, Expanded Material Options, Game-Changing Innovation

Reputation is everything. You may know us best for our taps, but for over a century EMUGE-FRANKEN has been developing and manufacturing milling tools — a wide range of solid carbide and HSS end mills, PCD and CBN inserts, and milling cutters with indexable inserts. In 2016 EMUGE-FRANKEN pioneered the development of Circle Segment Technology, introducing game-changing advancements for milling applications. 

Today, we are excited to announce the launch of our first North American end mill catalog. The NEW Catalog 420 features thousands of new items ranging from general application to material-specific cutters. And, just as you would expect from EMUGE-FRANKEN, our full end mill program is supported by a national team of technical sales and in-house milling application and programming experts.

For job shops and others machining a wide variety of materials, general-purpose end mills offer a nice balance between performance, tool life, and inventory costs. Yet some metals are either so difficult to cut or machined in large enough quantities that only the very best combination of carbide, coating, and geometry will do.