Hi!
I’m Jeff and I’m one of the many employee investors here at Gregg Distributors.
Today on Gear Up With Gregg’s, we’re going to talk about tap and die sets, and how they
can create clean, new threads.
And speaking of new, if you want to stay up-to-date on our latest content,
you can follow us on social media—just look for GreggLTD.
Now, let’s get to it.
First, you have to understand the difference between a tap and a die.
Taps make internal threads in a hole, which allows a bolt to be screwed into it.
Dies, on the other hand, make external threads on a rod.
Both taps and dies are used to cut new threads.
But how do you know which one you need?
Before you begin you’ll want to choose your tap based on the type of material you’ll
be threading into.
The most common taps are made of carbon steel for softer materials...
and High Speed Steel for harder materials like stainless steel.
This Procore kit is available in both styles, so no matter what you’re threading, we’ve
got you covered!
In order for taps and dies to cut, they need to be harder than the material they are cutting.
The type of steel and heat treatment that taps go through so they can cut metal also
makes them brittle, which means they can be broken—something you want to avoid at all
costs!
After all, the hardened material of a tap means it’s that much more difficult to remove
from a hole once it’s been broken.
But if you’ve already snapped off a tap in a hole… don’t worry!
You can check out our video on bolt extractors to find the best way to remove the broken
part.
To keep your taps in tip-top shape, you’ll want to make sure you’re using the right
tool for the job.
The tap wrench is the most commonly-used tool but proper technique is key to ensure
that you don’t break your tap.
Now, even though there’s not a lot of heat build-up when cutting threads, lubricating
the threads can help to reduce friction and aid in chip removal.
Chip removal and break-up is a critical part of the tapping process, since it helps to
clear out the chips of metal that are created when you cut the threads.
Different materials call for different lubricants, but something like this Rapid Tap
will cover everything you need a provide a nice finish.
See this groove in the tap?
It’s called a flute, and it provides clearance so that the metal chips can be pushed out
the top of your hole.
It’s important to break up these chips to keep the tap from jamming and breaking.
The best way to prevent this is to make sure that for every full turn forward, you
turn the tap one half-turn back, or until you feel those chips break.
This will ensure you are not putting any extra stress on the tap that could damage it!
Hand taps, which are the kind of taps we’re focusing on today, come in three basic types:
plug, taper, and bottom.
Plug taps, like this Viking HSS one, are the most common style and are often used for
general purpose applications.
They have a short chamfer that helps to start your threads nice and straight.
If you’re only purchasing one kind of tap, the plug tap is your best bet, since you can
get your thread started, and complete threads almost to the bottom of a blind hole with
just one style of tap.
A taper tap, on the other hand, starts narrow and tapers to its full width after 9 or 10
threads, hence their name.
This allows for an easier, straighter start when you’re threading a hole.
However, these taps will not be able to thread all the way to the bottom of a blind hole,
which is why it needs to be paired with the next tap I’m going to show you.
Bottoming taps, unlike plug and taper taps, have no taper at all.
That means that these taps don’t do well starting threads, so it’s recommended to
use a taper or plug tap to start.
However, they are the only tap style that can thread all the way to the bottom of a
blind hole.
Now, dies are basically the opposite of taps, since they create external threads on a metal
rod.
To prepare a rod for threading, grind a chamfer onto the end so it’s easier to turn the
die onto the rod.
Then, make sure to secure the rod in a vice.
Make sure the die and rod stay level and that you’re using lubrication where necessary.
For every full turn clockwise, make half a turn counter-clockwise to break up
the chips.
To clean up the chips in your tap or die, use a wire brush to remove the metal.
Then, check your threads with the desired nut or screw.
So now we know how to make internal and external threads, but how do you know what type and
size of thread you need?
In North America, and Canada in particular, there are two main thread series in use: SAE
and metric.
The SAE thread pitches are measured in TPI, or threads per inch.
Metric thread pitches are expressed as the distance between thread crests, so a thread
pitch of 1.0mm would mean that there is 1.0mm of space between the crests of two adjacent
threads.
If you’re unsure of the thread pitch, be sure to use a thread pitch gauge
to properly identify the threads you’re working with.
And, in case you’re really stumped, each tap and die kit comes with a chart displaying
corresponding die and drill bit sizes for every tap.
Here at Gregg’s, we’ve got a wide variety of taps and dies to meet your needs.
Whether you need a fully-stocked Viking Counter Display, a full Performance Tool tap
and die set, or just a set of taper pipe taps, we’ve got you covered.
Now, if you’re “dying” for more great content like this, be sure to subscribe and
hit that notification bell.
Or, you could visit our website or give us a call, and one of our awesome team members
would be more than happy to help you out!
Again, I’m Jeff, and thanks for watching!