How to cut an external thread using a die #1942

Another of the new 'Basic Skills' family of short videos, this one covers how to use a 'die' to cut an external thread on a length of rod.

Although this is more of an 'engineering' skill, there are occasions when, as a mechanic, you need to repair a part or maybe 'clean out' a damaged thread. This short video shows you the basics of how to perform this task, covering how to mount the die in the holder, the technique used to cut the thread and the things to look out for that may cause you a problem.

I don't just fix vehicles I often get asked to fabricate things too and knowing how to do this is a big help....

These 'Basic Skills' videos are NOT meant to be a decisive, all encompassing, training video on teaching you all the various aspects of professional skills, no, not in the slightest!

Its a short video showing the basics giving you a starting point on how its done, the tools you need and a few tips along the way...

Any questions then please leave them in the comments section below and I'll do my best to get back to you asap...

Andy Mechanic!

[crackedfingerz]

I like your red Tengu toolbox at the beginning of the video. Very unique. I customize all my stuff, too. Good, clear, and to the point instructional video. Well done!

[SivaFolsom]

Thank you, Andy! Your instruction is very clear on how to mount the die properly.

[wilfor]

Thank you so much, was trying to cut this stud now I'm on the straight and Day

[garystrobel]

Great video Andy. Exactly what I was looking for.

[jamesdoyle]

Thanks, really helpful video for me and hence now I've got some top tips for when it undertake it in the practical environment.

[davidmclaughlin]

Great tips! However, you didn't show how important it is to ensure you are cutting straight by measuring two sides of stock. If not even in two planes the die will cut at an angle. You mention it to be straight and with your train eye and experience it came out great. For a novice or a beginner measuring the two planes are the same is very important. As you gain experience doing this, you may get to the point that looking at the two planes like you did in the video will be spot on.

[petermarsh]

Dear Andy, thanks for the helpful video. If you were to attempt to cut a thread in a rod which is larger in diameter than your thread, how would you try it? I have been trying all sorts of tricks like a tapered cone and sanding the extra metal back but I end up with dog-legged thread cuts every time. If I had a lathe there would be no problem but alas, none are available for me to use. Any ideas?

[ac]

Great video! I am confused about UNF and UNC threads...do you need to use a different type of die for each type of thread or is this classification related to the number of threads (i.e. M6x1 being fine and M6x5 being coarse)?

[crotchetycomics]

Great video EXCEPT: The problem I keep having is not addressed: As much as I try to start the die level while threading the rod, the die starts gradually going off center as I'm cutting, so the threads start going off at an angle, looks like hell. I even have an adjustable self-centering die holder thats supposed to eliminate this problem. Why does no one seem to cover this?

[loutorres]

First of all excellent video. What type of steel was the rod used in this demonstration made of? Cold roll? Hot roll?

[James-mufn]

Great vid. Thanks. I do have a quick question. You mention making your own bolts and the thread part is obvious but what about the head? How would this work to tighten/loosen? Thank you.

[SpiceRoadNomad]

Can you make new but smaller threads on existing rod with threads?

[bathizargupta]

Mine often go off center or go crooked. Is there a jig that keeps the die and holder centered?

[ariesmars]

I have a question. I can't seem to get a die to thread on any steel I use. I turned a piece of steel to 8 mm and tried to thread it with a 8 mm x 1.25 pitch die and I could not get it to thread. I even put a chamfer on the end, still could not get it to thread. I turned the steel to 7.9 mm and then 7.8 mm and still could not get the die to thread. Why are there no charts for dies' as there are for taps? I looked at the die for the start on this side, but the die have very little taper to them as they look the same from both sides. I'm just a hobbyist so I don't have the greatest tap and die set.

[Nox]

what's the name of the track playing in the 1st 30 secs?

[evank]

Pitch is 1.5 and m10 isn’t 10mm. There’s a chart online. More like 9.8