Tap and die sets are an extremely handy tool. Whether you are mending damaged thread or threading new material, having a quality tap and die set on standby for the job is what you need.
However, as with any tool, to get the most out of it and to perform the best quality finish there are some procedures you should follow.
Not only will you get professional looking results, you will also decrease any unnecessary wear and tear on the set.
So for some best practices when using a tap and die set, keep on reading.
The two types of threading
Threading with a tap and die is divided into two types; internal and external.
Internal threading
Internal threading is self-explanatory. It is the thread that is created inside a piece of material.. This is carried out using a tool called a TAP. A hole is drilled (to the diameter of your choosing) and then a thread size and pitch is created.
External threads
External threads are used on bolts and studs. The die is used for this type of threading. Applied to a specific diameter of rod the thread is created on the outside of the material so that it can be screwed into a internal thread of relevant size and diameter.
As mentioned in the introduction, taps and dies can be used to either cut new threads or repair damaged threads.
Types of taps and dies
You will find different types of Taps and dies on the market. The most common is High Speed Steel (HSS) for softer materials.
When threading harder materials it is recommended that you use Cobalt stainless steel.
Top brands utilise platings or coatings designed to increase the cutting ability of the set. To find out more about some of the best tap and die sets available head here.
Best practices when using a tap and die set
Handle your tools with care
Even top quality taps are quite brittle.
The rule of thumb when using a tap and die set is to ensure that the material the set is made from is harder than the material being cut, (that’s why a cheap set is not worth the time or money, you will limit yourself on what you can actually thread).
However, the hardness factor has a trade off in that the tap and die are more brittle. Essentially, if used in the wrong way you can end up breaking your tool.
T-handle should always be used for taps, (avoid picking up a pair of pliers or a locking wrench as these can put unnecessary strain on the tap as you turn).
Using a T-Handle works better because they are designed for the job in hand. They exert force over the center of the tap or die, meaning everything is balanced.
Lubricate the work material
Because you are threading metal the force generates heat.
This heat needs to be reduced in order for the material to keep its integrity. Heat will also damage your tools if left unchecked.
That’s why lubrication is so important.
Not only will lubricating the cutting threads help reduce friction it will also help with chip removal.
There are special tapping fluids available, however if you do not have any of this, some WD-40 will suffice.
- Related Content: How to use a tap and die set the right way
Slow and steady wins the race
To get the best results you simply need to take your time. Rushing a job will lead to bad results.
Worse case scenario you could end up breaking a tap off in a hole.
Even if you are seasoned pro, it is recommended that you use the tap and die set carefully and slowly. This way you will get the professional finish you are after without any damaged thread or tools.
Remove the Chips
Now we get on to the subject of chip removal.
It is very important that you break up the cuttings to prevent jamming and breaking the tap, (see video above if this does happen to you).
You can do this by turning the tap in the direction of cutting. Do this until you start to feel it bind.
When this occurs you only need turn the tap slowly in reverse so that you hear the chip breaking away from the material.
You will find your tap will last so much longer if you remember to carry out this simple technique.
Follow these tips and not only will you produce better threads, you will also keep your tap and die set working as it should for many years to come.
Image Credits: Sealey.co.uk, The Golden Wench, GearWrench.com, Photo by Jordanhill School D&T Dept / CC BY
