Four methods for cutting internal, external, left handed and right handed threads on the lathe

Follow my journey leaning how to cut threads on the lathe. We look at four different approaches to screw cutting from easy to more advanced methods. We look at cutting not only right handed threads but also left handed threads, internal and external threads, measuring threads and cutting metric threads on an imperial lead screw and imperial threads on a metric lead screw. We also have a sneak peak at engraving metal with a fibre laser.

Check out the fibre laser at the following links, use code 'Joneseymakes' for an extra $100 discount.

US Store:
EU Store:

Support the channel and download the cut files for toolboxes;

Buy project plans, 3D printable items and merch!

Check me out on instagram;

Timestamps
0:00 Introduction
0:23 How is a screw thread formed?
03:58 How to configure a lathe for thread cutting
04:58 Thread cutting - Method 1
07:04 The threading dial
10:20 Understanding thread dimensions
12:05 Thread cutting - Method 2
14:48 Measuring threads
16:24 Cutting left hand threads
20:55 Cutting internal threads
23:42 Left hand internal threads
24:52 Internal threading in blind holes
25:04 Engraving metal with a fibre laser
25:45 Thread cutting - Method 3
28:45 Cutting imperial threads with a metric lead screw
29:18 Thread cutting - Method 4
31:46 Conclusion

[miojoriginal]

Love your videos, man
Just a heads up, the compound should be set at 60.5° actually. Due to the direction of the scale, you should set the complementary angle of what you intended. In other words, you should subtract the angle you want from 90° (90° - 29.5 = 60.5°). The way you set it, the angle was equivalent to 30.5°.

[savio]

I'm so glad you got the flats of the nut's to align by the end of the vid, I did wince a little half way through watching 😂
That alone has gained you a new subscriber! 😉

P.s. Top marks for the content too, was very helpful for a muppet who's just bought his first lathe ⭐

[earlhuff]

Method 3 is all I use. Stress free cutting. Never worry about the crashing into the shoulder and as you said you can thread much faster.

[joemcgarry]

I almost always use method #4, leaving the lead screw engaged. I retract the tool, and reverse the spindle simultaneously. That is the way my Dad taught me 60 years ago. I only use the threading dial when I am cutting a long thread. Great video! Solid information, and instruction.

[HexenzirkelZuluhed]

Great summary. The laser markings look beautiful. Looking forward to the video.
Even with method #4 you CAN disengage the half nuts, if you reengage them at the same value on your thread-dial when running in reverse.

[MyLilMule]

Lots of good information here. I would add that when cutting left hand external threads or internal right hand threads, it's necessary to move the compound to the opposite 29.5 degree angle so the forward edge of the insert is making the cut rather than the trailing edge.

[EZ_shop]

Excellent video. A couple of questions... What is the purpose of the second smaller tooth on the screw cutting tool? and... How did you get the nut faces to line up with the middle "nut" at the end of the video? Ciao, Marco.

[fouadsharif]

I am a 70 years old Tool Maker....and I take my hat off as a matter of respect....well done Sir....perfect video....

[ChickenHawk]

I have watched many videos that explain single point thread cutting but I think yours is the most thorough and informative. Very well done, friend. Great pace, great visuals, and most of all you don't hide your mistake of cross threading!

[andrewdolinskiatcarpathian]

Hi Jonesey. Thank you for a very interesting overview of single point thread cutting. Very enjoyable.
Looking forward to you showing more about your new laser engraver. 👍😀

[bradwallace]

Excellent explanation for newbies.
Like how you included your flub for honesty.

[alexgaras]

Nice to see someone really getting down to the nuts and bolts details of it 👍👍👍 Great video

[someotherdude]

One of the very most enjoyable videos on machining I've seen, Thank You.
Fun bit of threading that is possible: Threading a piece of shafting like you have done (bigger is better) with both left hand and right hand threads, and then fitting both a Lhand and Rhand nut to it. Yes you can even combine this into one nut, but it gets messy in the nut and hard to clean up.

[billshiff]

29:30 You CAN disengage the half nut at the end as long as you re engage it on the same number and rotation it was on to begin with. Just don't let the dial make a full turn and put it back on your marked line when you reverse it.

[newt]

I have a WEN mini lathe, and it has a reversing lever for the lead screw on the back of the machine.
Love your videos.

[lrita]

THANK YOU!!! You answered all my questions I’ve had about how the lathe parts work together to create threads.

[ThantiK]

Honestly for the mini lathe, I think adding an electronic lead screw is a great idea too.

[dazaspc]

It was probably worth mentioning a few things.
Cutting tips for screw cutting are very often R/H OR L/H thread use only as they don't have the proper clearance. Some have adequate for both but it is worth keeping in mind.
When cutting L/H external with your 2nd method the compound slide needs to be rotated around so it feeds in the direction of cut like it does when you set up the R/H example. this keeps the cut on the leading edge.
There are other methods of cutting threads using a calculated move on both the cross slide and the compound but you need to calculate the movement to keep in sync with the thread angle.

[bobmac]

One method most shop never consider? OD-Thread rolling and yes it can be done on most old and new CNCs machines. Fette Rolling heads. Many units we sold even went on old Warner & Swasey chuckers.
There is a cost savings by ordering steel bars at PD-pitch diameter. The material is displaced. And the time saved is huge.

[billshiff]

21:00 Actually the profile of the cutter for an inside thread is not the same, it requires a smaller radius on the nose for inside threads.