Why should I use thread forming taps?
Thread forming taps produce threads by displacing the material rather than cutting and removing the material to form the thread. This essentially cold-forms the thread, producing a strong thread. Another benefit of thread forming taps is that they do not produce chips like a cutting tap would. Forming taps are known to also provide extended tool life due to the fact that there is no cutting action, there are not sharp edges to dull. They also stronger taps by nature because there are no flutes. Larger sizes of forming taps have what are called lube-grooves, to allow some clearance for lubricant and enhance the performance of the taps. These lobes are visibly if you look at the tip of the tap. You will notice that the forming rings on the tap are not perfectly round, but have lobes.
What materials should I use them on?
Any material that produces a stringy chip is a good candidate for thread forming. They are most commonly used on aluminum, brass and other non-ferrous metals, however the can be used on certain grades of steel and stainless steel. Most ductile materials producing stringy chips are great for forming.
How should I use thread forming (roll) taps?
Thread forming taps require different application parameters than standard cutting taps. Here is a link to our recommended speeds, feeds and hole sizes for your thread forming operation.
Did you know that all of are taps are designed to be used under power?
Sometimes if is a little confusing, because standard straight flute threading taps are often referred to as hand taps, that they are also used in machine applications. There are accessories available for using these taps by hand, such as tap handles, tap wrenches and tapping alignment tools, but the standard straight flute taps can also be use for smaller run machine tapping. All of our standard straight flute taps are made from premium grade M-2 high speed steel material, to provide maximum tool life. For additional tool life you can also consider a coating such as TiN or a treatment such as Steam Oxide or Nitride & Steam Oxide.
Take a look at our tap selection here: http://www.kodiakcuttingtools.com/viewcategory/taps
How do you run a double-lead tap?
As you probably already know, a double-lead tap traverses twice the distance per rotation as a standard tap would. The question of how to run them comes up from time to time, so we thought this would be a good entry for the technical section of our speeds and feeds blog.
The feed rate will be twice that of a regular tap, so to compensate, cut the RPM that you are running at to about 1/2 of what you would run a single lead tap at.