Successful Threads With A Die

While the Tap & Die go hand in hand as threading tools, they’re very different in the way they work.  There are also different tricks for success.  So, let’s talk success tips for making external threads with a die.

The Tap and Die are both cutters for making threads.  Taps have teeth on the outside for making threads on the inside.  Dies are the opposite with teeth on the inside for making threads on the outside.  For typical DIY, taps are much more common, and are easier to use properly.  Dies are less used (fortunately), and come to failures more often (unfortunately).  Mostly, we buy external threads in the form of a bolt, but there are times when we need to create them, so one way is with a die.

What Is A Die?

Tap & Die for ThreadsRemember this picture?  It comes from our article on tapping for internal threads.  The long straight parts in this image are taps — for cutting threads on the internal surfaces of a hole.  The round cylindrical parts in the image are dies — for cutting threads on the external surfaces of a cylinder.

For reference, the “inside” story on threads — tapping internal threads — is covered in the article “Get Thread Tapping Straight“.

Today, we’re talking about dies, and tricks to making good external threads.

For DIY there are 2 really good uses for dies.  The first, for chasing threads; and the second, for creating them.  The first, chasing or clearing external threads with a die, is the simpler case, so let’s start there.

Anatomy Of The Tool

A die is a pretty simple looking tool.  It’s like a nut, but with interrupted internal threads, the edges of which are the cutting teeth.  Thread dies are often round on the outside like in the picture, but they are sometimes hex or other shapes.  Just like taps, they come in different configurations like with 3 or 4 or 5 or more columns of threading teeth.  While specialty dies come with teeth shapes for cutting particular materials, general purpose dies are usually good enough for DIY.

Thread dies have a front and a back — or more accurately, an entry side and an exit side.  You can tell the entry side because it has a relief in the cutting threads — with reduced height teeth for starting the cut.  The relief in the entry side also helps center the die on the cylinder to begin the thread.

Clearing External Threads With A Die

Have you ever tried to turn a nut onto a bolt and found there is a burr or something in the threads that makes it difficult or impossible for the nut to pass?  There are several ways to conquer this, but one is with a die.

So, I have to caveat this trick with a couple things.  First, if the bolt is really hard, like grade 8 or 10.9 or something similar, the die might not want to cut a serious burr.  Second, depending on how the bolt threads were created, a die might want to peel the threads all the way down, and that can cause it’s own problems.  (When the original external threads are super accurate and “tight” fitting, a general purpose die will cut them less accurate and slightly looser fitting.  It’s not often a problem, but it’s worth mentioning.)

Clearing threads with a die is a cool trick, but it doesn’t always work perfect.  The ideas is to simply thread the die onto a shaft, just like you would a nut.  As you turn the die, it trims off burrs and damage leaving a nice thread again.  Obviously it can’t put back material that moved, but it can cut off the burrs to clean it up.

External Threads With A Die

The real trick to success is making sure it goes on straight, and to make sure the die comes nicely into the existing threads.  If it doesn’t align right, it will cut new threads on top of the old ones, and that will totally ruin the part.  “Cross Threading”  Anyway, take some care that things align, then this trick will fix the damaged threads.

Creating New Threads

When we think of a thread die most of the time, we think of cutting new threads.  Effectively making a bolt.  If that’s what you need, then for sure, the die is a great tool to accomplish it.

The concept is simple — place the die on the end of a shaft, then start turning the die.  As the die turns, it cuts new external threads.  Right?  Yes, that’s the concept.  Doing it right is the issue.

The first few times I tried to put threads on a shaft, I ended up with a mess.  Turns out it’s really hard to get the die on straight when you’re doing it by hand.  I ended up with a new thread that was slightly cattywonkus to the shaft.  I don’t have a picture, but imagine the threads going at a slight angle to the shaft — where the further down the shaft the threads get deeper on one side and shallower on the other.  Eventually the die won’t turn anymore, and the part ends up as garbage.  The unfortunate thing is there is no way to correct the issue once the threads are cutting, and you can’t tell you’ve got it wrong until the threads are there.

The trick is to use something that forces the threads to start straight.  Here’s a video of how I do it now.

Video:  Cutting New External Threads With A Die

Here’s a quick video showing one technique for using a die for good external threads.  Just to make it hard, we show a thin wall stainless steel tube, welded seam.  Enjoy the video.

So if you’ve ever had trouble — like I have — with getting a die to start truly straight, that’s a good technique.  There are not too many times when a thread die is really needed, but when you do, then it’s sure nice to have one.  Like the tube in this video — I did not want pipe threads (and they wouldn’t fit that diameter anyway).  So, a thread die does the trick.

Instead Of A Die . . .

Bolt For A StudWhile the die is right for many jobs, there are substitutes that can come in handy instead of the die.  The first, and most beautiful is a friend with a lathe.  While that’s not always available, how about variations of bolts.  On many occasions I have cut the heads off bolts to use them for something.  Bolts are cheap comparatively, and they’re a bunch stronger than material you can cut threads on.  One example is shown in the image.  I needed a peg with threads, so I just cut the heads off bolts, then rounded the needed end with an “essential” grinder.  Works perfectly.

Other options include using bolts or threaded rod, or something similar.  For instance, welding a bolt sticking out of a chunk of tube for a long hollow shaft.  The possibilities are endless for substitutes, but now you know a good trick for creating external threads with a die, you don’t always have to find a work-around.

Good Luck With All Your Threading!

Comments

1 Comment
Inline Feedbacks
View All Comments

We Found These For You . . .

Article
Shop Utility Floor Cart
When there’s a need that doesn’t really fit with existing products, make your own.  That’s it with this new, tough Shop Floor & Utility Cart.  While it’s not monumental in design, it does have some great functionality for DIY’ers, with…

Read The Article

Article
Example aluminum trailers
This question comes up often — because there are not many good plans for aluminum trailers out there.  We have great trailer plans, but none for aluminum.  Why?  As one of our Frequently Asked Questions, this one deserves a good…

Read The Article

Article
New Deck-Over Trailers Plans
More new plans, and even more coming.  You’ve been asking for robust Deck-Over Trailers, so that’s what we’re working on.  Now they are here, and we’re not talking about another “Me Too”.

Read The Article

Product
6x10 Heavy Duty Trailer Plans

For all the jobs a utility trailer must do, these plans include so many options for both function and utility.  At 6+’ wide 10’ length, this design also includes an axle option for 6000 lbs or 7000 lbs.

Article
Finishing or Trailer Frame Painting
(And finishing other DIY Projects.) Now you’ve invested all that time and effort into building an awesome trailer, how should you finish it?   Of course we don’t want it to rust.  And, we want it to last. 

Read The Article

Article
Using A Workshop Hydraulic Press
A shop press is a fantastic tool, and when you need it, there’s not much that can really substitute.  On the other hand, we need to keep things in order because when things go bad, they can easily go really…

Read The Article

Article
Trailer Hitch and Drawbar Classes
As a convenient way to help with safety, trailer hitches, balls, and receivers have categories or load rating groups called classes.  Each trailer hitch class has ratings for how much it will carry.  A look at the ratings for each…

Read The Article

Product
5x8 Trailer Plans, 3500# Capacity

Start building your own utility trailer with these 5x8 Trailer Plans.  Blueprints are fully engineered and include options for various needs.  These plans are a perfect map for a great project.

Article
New Trailer Test Ride
When the rubber meets the road, that’s when the feeling of real accomplishment kicks in.  This is the first on-road trailer test with (with video) of our new frame and funky walking beam suspension design.

Read The Article

Article
Trailer Tire Comparison
The topic of trailer tires has come up a hundred times.  Why can’t I use automotive tires on my trailer?  That’s a fair question, so let’s explore it.

Read The Article

Product
Tilt Top Trailer Conversion

Convert our standard Utility Trailer Plans into a Tilt Top Trailer with these Conversion Plans.  It fits our smaller, 3500 lbs, utility trailers in 4' width and 5' width — for both leaf springs and torsion axles.

Article
Wide and Wider Tiny House Trailer Plans
What if . . . You want to live Tiny, but not “that” tiny?  Sure, there are a lot of attractive elements with living Tiny, but to some, the 8 foot width is just too tight.  If that’s you, go…

Read The Article

Article
Thread Tapping Straight
A Tap and Die set is a near must for a DIY fab shop.  While the thread creating functions are pretty easy to visualize, sometimes getting the tread to start straight and run true is a different matter.

Read The Article

Article
Timbren Axle-Less Trailer Suspension
Customer Question:  “What do you think about the Axle-Less trailer suspension?  Is it good?”  Can I use it with the Mechanical Elements trailer plans?  . . .  You ask (actually a few of you are asking) and pointing to

Read The Article

Article
Makeshift DIY Truck and Trailer
The coolest thing I saw last week was this guy with a very creative DIY approach to a pack trailer — and, of course, his tow vehicle!

Read The Article

Product
32' Tiny House Trailer Plans For DIY

With options for length, these blueprints address the unique needs of a Tiny House Trailer.  Low 8.5’ x 30’ or 32’ top deck height.  Up to 18,000 lbs total capacity.  Fully Engineered.

Product

An excellent DIY small trailer project.  These 4 x 8 Utility Trailer Plans sport 2000 lbs. capacity.  The trailer will work hard, yet always be nice to work with.  And, tow it with a smaller car.

Product
6x16 Tandem Axle Trailer Plans

Build a great tandem axle, heavy duty utility trailer from these 6x14 trailer plans.  Blueprints are fully engineered for 12,000 lb. total capacity.  The trailer you build will be tough and ready to work.

Article
Don't Look at the Mig Welding
I grew up with a fascination for metals.  My father was a woodworker, and taught me young, so I have always built stuff from wood.  Yet, metal is different, and welding beats glue in the fun department any day!  And…

Read The Article

Product
6x14 Utility Trailer Plans

Get your 6x16 Utility Trailer Plans here, then build your own 7000 lb. capacity tandem axle workhorse.  These plans include all the details and instructions.  Build it, and make it better than you can buy it.