203 Almost Everything I Have Learned About Threading

Chapters:
00:00 Intro
01:59 Thread Making Overview
03:34 Thread Forms
11:34 Thread Making Tools for The Manual Lathe
18:34 Threading Inserts
22:35 Manual Lathe Machine Controls
25:09 Saddle Controls
29:30 Compound Angle Controversy or Not
32:17 Traditional Thread Cutting Demo
45:41 Threading to a Shoulder with NO RISK of crashing
53:16 Left Hand Thread Summary
53:45 Multistart threads
Please Note: I am a beginning machinist and I do not pretend to know everything. Please always operate machinery in a safe manner and if you don't know, find a reliable source. DO NOT COPY ME. I make a lot of mistakes. I provide these videos for entertainment only.

[@ronald44181000]

The best threading video ever with the added exposure to the upside down method for cutting threads away from the chuck.

[@DudleyToolwright]

That was very kind of you thanks. I was trying to make a reference video for those starting out. I will try to update it when I learn more or have time to demonstrate other thread cutting techniques. It took three weeks to make and I still didn't demo everything, like internal threading.

[@christophercullen4889]

Best video I have seen on threading . Christopher from Down Under

[@DudleyToolwright]

That is very kind. Thank you. I will post an updated video at some point to cover some items I missed, like metrology on threads.

[@RGSABloke]

Joe Pye’s technique running the lath backwards started at the end of the thread working backwards.

[@DudleyToolwright]

Yep. He is a superb teacher.

[@RGSABloke]

You too sir are an awesome teacher with great content on your channel. Kindest regards from Bonnie Scotland. Joe.

[@ShadonHKW]

Nice presentation Robert.

[@DudleyToolwright]

Thanks Stan. You did a really nice review of the punch press. I have been considering one of those for a while with Vevor. Now I think I want one.

[@a-k-jun-1]

I believe the carbide anvil is for production tooling to reduce wear on the tool holder and is replaceable when it does show wear.

[@DudleyToolwright]

Thanks for the info!

[@mchiodox69]

All the info in one place....awesome. Many thanks for putting this together.

[@DudleyToolwright]

No worries. It was what I have been looking for for years. I will update it as I know and have done more.

[@frankward709]

That was fun, Very well done Thanks for the video

[@DudleyToolwright]

Thanks. I am very glad it wasn't to dry a discussion.

[@7alfatech860]

The close up view of the threading inserts, IR vs ER was really nice. This should be a nice reference video for many. I know I had to do a lot of searching to figure out the difference.

[@DudleyToolwright]

Yea, I really had to do a lot of searching over my limited career to learn what I demonstrated in this video. I was trying to create a one stop shop, that was also clear enough to follow. I might revise this video as I learn more.

[@iteerrex8166]

Yes it’s definitely gona be a reference video for me, being new to machining.

[@RRINTHESHOP]

Well done Dudley. There is so much to threading.

[@DudleyToolwright]

Thanks, Randy. I try to subscribe to every machining channel to help the new guys out and now have so many subscriptions that it is hard to notice notifications of the ones I really am interested in, like yours. I need to head back there and catch up. Is Tom somewhere near you?

[@RRINTHESHOP]

@@DudleyToolwright Tom is about 3 hrs north of me. LOL

[@richarddechau4200]

Great video the only thing Joe made sure he mentioned that the lead screw and the chuck are running in the same direction for right hand threads. Once I watched Joe's video a year or so ago I always thread this way know.

[@DudleyToolwright]

Good point. Thanks for the correction. I think there is a lot more I can add to this video, so I intend to amend it in the future. I will add the changes you have suggested.

[@richarddechau4200]

@@DudleyToolwright Merry Christmas. Keep those videos coming. Rick

[@kentuckytrapper780]

Great info DT, a lot to study, great video, keep'um coming.

[@DudleyToolwright]

Thanks, will do!

[@outsidescrewball]

Enjoyed…happy holidays

[@DudleyToolwright]

Thanks Chuck. Happy holidays. I hope you and your family are doing well.

[@iteerrex8166]

Essentially a thread is a wedge, a circular wedge. Like an adjustable parallel, but circular. Say the top triangle be the bolt, and the bottom half the nut. The cool thing is that the force applied is transferred 90° to the direction of force, and with a little bit of friction, it stays put and doesn’t push back, or unwind. Thanks DT, I’m new to machining so well done educational videos are great 👍

[@DudleyToolwright]

Thanks. I tried to make my explanations understandable, but it is harder than expected. The guy on some of these channels seem to put out incredibly clear explanations with little effort. That was definitely not the case here.

[@iteerrex8166]

@@DudleyToolwright The video is great. It was clear and understandable to me.

[@trollforge]

Thanks Robert, you've answered my questions on Acme inserts! You can certainly tell you don't work on British bikes or cars, Witworth threads are very common there...

[@DudleyToolwright]

I never have and was under the impression that Whitworth was a thing of the past. Are the still used today in the UK? Sub'd.

[@trollforge]

@@DudleyToolwright to tell the truth, I've never worked on anything newer than the 80s so you may be right. But China seems to produce ~100 times more Wittworth than UNC/UNF, judging by AliExpress... Oh, and thanks, but be warned, I am a Homesteading Channel , I do a lot more than shop videos...

[@hilltopmachineworks2131]

Well done! 👍Only issue I have is my 13x40 lathe the half nuts are always a bear to engage. Which makes it possible to miss your number or line and you have to disengage and try again. Threading towards the chuck gives me enough time and room to do that. If I am threading away from the chuck and I miss my number or mark on the threading dial then I have already started cutting and messed up the thread.

[@aceroadholder2185]

You need to pull the apron off the lathe and inspect the half-nut mechanism for poor fit and finish (a common problem on mainland Chinese lathes) or damage to the half nuts themselves. The half-nut should engage smoothly without forcing the lever. For threads 12-24tpi on my 12x24 lathe I usually run at 290 rpm.

[@DudleyToolwright]

Hey Tom. My lathe's half-nut is more difficult to engage at some numbers than others. 1 is by far the easiest and it's not because I use that number more than others. Weird huh? I have also engaged the half-nut just before or after the line and hosed a thread before. It seems like this risk is more prominent at certain thread pitches, although I haven't identified the pattern.

[@hilltopmachineworks2131]

@@DudleyToolwright I may hit you up for one of those 6 pitch acme thread cutting carbides. I need to make a new nut for my bandsaw at some point.

[@Jeff-zc3wl]

Carbide anvils can be ground at different angles, sometimes needed for fast pitch or multiple lead threads to prevent heeling on the back side of the insert.

[@DudleyToolwright]

Thanks! Can you explain what you mean by heeling on the back of the insert, please?

[@Jeff-zc3wl]

@@DudleyToolwright I should not have said the back side of the insert, but rather the flank. If you picture a standard RH threader trying to cut a 4 tpi acme thread, the helix angle of the thread can be larger than the relief angle of the insert. This causes rubbing (or heeling) on the flank of the insert instead of shearing at the cutting edge. Trying to cut a LH thread with a RH tool will similarly rub.

[@dsmith7455]

Good complete overview of threading. Any complexities with internal threading?

[@DudleyToolwright]

It is the same except for the lack of visibility and possibly more tool deflection. I will update my threading video to include examples in the near future. I also missed metrology, which needs to be addressed.

[@gerritvisser]

I find the tip width of A60 inserts are wildly optimistic relative to the claimed pitch range. Too wide for the fine end, too narrow for the coarse end. I often have to use my optical comparator and d-bit grinder to align the tip width with reality. Great video, solid info.

[@DudleyToolwright]

Interesting observation. I haven't tried to push the envelope...but really good to know since the majority of my inserts are inexpensive Chinese ones.

[@torsiondell]

Just watched your video very informative but I think you should have mentioned that if someone has a lathe with a screwed on chuck then unless very careful do not thread in reverse as it can unscrew the chuck, my Myford has a screw on chuck but I have installed Rocketronics ELS so don’t need to do it, apart from that an excellent video.

[@DudleyToolwright]

I forget that other lathes use other than D style chuck mounts. Thanks for the reminder. It is definitely worth a mention.

[@PaulMorley1]

Thanks Dudley. Great vid. I'm only a couple mins in and noticed something interesting about the first thread diagram you showed at 1:44. When you superimpose the red lines to show the lead angle it struck me that the roots as well as all of the other elements of the thread follow a slight s-shape. I had never noticed that before in other diagrams but I am finding it in some diagrams i'm looking at on google now. I suppose it's not really that important but I am curious if it's just an illustration technique to try and convey roundness of the part. Just found it interesting since it actually seems to suggest a wavey nature to the thread cut.

[@DudleyToolwright]

I noticed that too and was also taken a bit aback. It seemed as if they were trying to show the helical thread simulating 3d or something. I chose the image because it showed thread lead, in spite of the strange rendition.

[@nunosantiago2273]

Wow. Thanks for this great video. I'm saving it. Do you know where I can get the Black Book?

[@DudleyToolwright]

Thanks. You can find the book here: www.engineersblackbook.com/ or amazon.

[@billshiff2060]

You didn't mention anything about what class thread you were making or the tolerances of the 3 classes. Also at 32:39 what are those things on the two strips?

[@DudleyToolwright]

I forgot to mention thread classes, thanks. I intend on updating this video at some point and that topic would be a nice addition. The items on cables that you wondered about are thread checkers - one metric and the other imperial. For each size they have a male and female thread. Really handy tools. Here is a link to the ones I bought: www.amazon.com/dp/B06ZYD4SS8?linkCode=ssc&tag=onamzrobe04a7-20&creativeASIN=B06ZYD4SS8&asc_item-id=amzn1.ideas.1RV7BHP4BGAHF&ref_=aip_sf_list_spv_ofs_d_asin&th=1

[@le3045acp]

excellent 1 question how would you make the female part for the multi start thread ?

[@DudleyToolwright]

You make it the exact same way but using a threading boring bar. I knew I should have demo'd at least one internal thread.

[@davemason6273]

Well put together Dudley. Only a couple of things I thought you could have added, safety regarding screw on chucks, and the use of thread wires.

[@DudleyToolwright]

Absolutely great tips. I will add them to my list for updating this video at some point.

[@baremetaltechtv]

I do some NPT threading at my job where I machine pipe stub ends. Basically a pipe with a flange on one side, and occasionally threaded on the other side. We make stub end pipes from ¼ inch up to multiple feet in diameter, flange is completely machined and not press fit or welded onto the pipe. As far as machinist jobs. It's kind of boring making the same part every single day just different sized. I'd rather do general machining and make lots of different parts, but that's life I guess 🥱😅🙃😁

[@DudleyToolwright]

I totally forgot to cover tapered threads, which I am not sure how to make without a taper attachment. Thanks!!!