Nicely done sir. In the early 80's I was fortunate enough to have my employer fund a full 5 year mechanical engineering apprenticeship. This Brough back happy memories. Excellently and precisely explained.
Thank you. I'm glad you enjoyed it. I too was lucky to be in a similar situation where my employer at the time put me through college. On the job training or 'learn as you earn' is a great way to gain both knowledge and experience in my opinion.
This is the method I have learned on the manual lathes. and always used. I used to make spindles for axles on semi tractors and stuff. Then I went to school for CNC and was smitten. Thank you for explaining this so well
My father used to do a 14 feet long shaft with ease. I was about 11 or 12 years old maybe. He was a great turner. Passed away in 2012. Wish he was alive to teach me all this stuff.
Superb video mate,& demystified manual threading massively for me- been having to use retention screws instead of threaded parts on my hobby project due to lack of time to get trained up,& this has given me a mental grounding in the process to get started threading future builds.Brilliantly clear explanation- much obliged,sir!
This is a good, thorough, tutorial covering ALL steps in setting up the machine. I would offer to immediate improvements to ending up with a better thread. The first being a faster spindle RPM. It appeared the RPM chosen was simply the slowest ...which is fine. But the problem is this cutting speed is in fact very slow ....on purpose. 1) A faster CS would automatically provide a better finish on the thread form. But this is up to the operator and their comfort zone with operating the half-nut disengagement only, for this one example. As determined and explained, for this thread pitch, any of the 8 engagements on the thread dial indicator will keep the pitch ...so there is no challenge factor in engaging ....and this engagement can be as far away from the thread start point aw the operator chooses. It is the "disengagement" that is the critical point ....but this is also dependent on how wide the relief is. Nothing wrong with practicing this technique. It just requires concentration. 2) The depth of cut chosen was very deep on the second pass. Considering the extremely low RPM, this resulted in extremely poor surface finish because the metal was literally tearing off the parent material ....and the surface finish looked awful. The depth extreme depth of cut can be taken, but it need NOT be that deep. As the final thread depth of cut is approached, the actual cutting depth should be reduced, simply because there is more material being removed at the deeper cuts. 3) And lastly, it is very common practice to run at least one "extra" pass after the last finish depth has been reached. Even though this bar is supported on a center, the bar material still deflects. There was a lot of tool pressure still on the last cut. A "cleanup" cut just makes sense to perform. It will literally always improve the thread surface finish as well .....which is what the female thread is going to be running on. There wasn't very much offered about "fitting" the thread and the testing of the nut did not reveal very much either nor was there any mention about the fit/class .....but considering this was only a tutorial using the cross-slide, ....enough said.
That was a brilliant lesson on thread cutting. I'm a very keen hobbyist and self taught. Your lesson has taken away most of the scary stuff for me. Thank you very much
When I started my apprenticeship, I was taught how to calculate the thread depth (using simple mathematics). The second thing I learned is that when you did the final cut and the nut fits perfectly, NEVER to use a file on the thread or "scotch brite". The thread should be smooth and shiny. In this video, you can see on the "chip" that there is chatter. However, a good tutorial for a beginner !
Yeah, this video is pretty scary to watch. He's going way too slow to get a good finish and I don't understand why you wouldn't turn the compound to decrease chatter.
@@spazzwazzle he said that there are better ways to do the job ...but this is a fairly basic method with less chance to make mistakes... i am sure he could do if he wanted to
Many of your viewers (me, for instance), have less rigid lathes. If I try to plunge-cut a 1.5mm thread on my seventy year old Myford Super 7, I will end up with a lifetime supply of chatter marks! For lesser beings like us, the 29.5 degree compound slide method is our saviour! Sadly for me, my lathe is also short of its thread-cutting dial... My father bought the lathe when I was five years old, and gave it to me thirty years later, so I know it did not ever have a dial... might be a project for me. 😜 Great video, thank you. It did drive me la-la though; your voice is very familiar, but I could not figure out why! 🥴 As an afterthought... because the Myford has a clutch, I can make a cutting pass, disengage the clutch and withdraw the tool, then wind the carriage back using the handwheel on the leadscrew. This is actually a very quick process, and works great with the 29.5 degree compound, and no threading dial... it's also pretty foolproof. 😛
My two cents worth……..engaging and disengaging the half nut lever is only done when you are cutting very long threads. With most typical threads such as this you simply withdraw the tool quickly at the end of cut and put the machine into reverse to get back to your start.
I agree. Where you disengage and engage the half nut, it doesn’t always go back exactly the same. Especially with an older lathe. You can easily cut the thread too deep or too wide usually when doing final cuts.
Flip the tool upside down, and start the tool from the chuck side and feed toward the tailstock and run the lathe in reverse. Learned this from the best toolmaker I have ever know who was from Germany. Many advantages, the most important is that the chips fall down out of the groove instead of bouncing around in the groove and ruining the finish. Running off the part at the end is more forgiving and gives you more time to disengage the half nut, therefore you can run the rpm higher for smaller diameters. And no, you won't cut a left hand thread this way.
Great video .. in my school days we did so much theory on how lathes worked and then never got to use one.. now I'm at an age I can maybe buy my own and learn.
You just earned a subscriber. Just started to look for a metal lathe and gathering some information on various techniques and this one is very concise. Excellent job !!!!
Just found your channel as I've upgraded to an M300 from a Myford and liked your RPC video. If you're just doing a simple "plunge cut" threading job and you have the nut handy for sizing, advance the top slide a couple of thou every cut, this mimics the angled top slide method and let's the tool cut primarily on its leading edge, reducing tip loading and generally provides a smoother finish to the threads.
Nice video for demonstrating cutting metric threads, may also add depending on what brand of lathe swapping gears to do metric or atandard threads. Ive been cutting threads on old school lathes for 35 years myself,over all great video
I was taught to turn tool upside down, run lathe in reverse, and cut from chuck towards tailstock. This reduces the risk of a crash into the shoulder, and no need for a large undercut. I always cut threads this way, and have done for last forty-five years, unless using an Ainjest attachment.
Dude this is so great. I have always wondered how this worked. Because I have seen loads of videos where the camers is focused on the cut while threading but with no explaination. I just assumed the person using the machine practiced their timing enough that they were just that good. I am not ignorant enough to assume it was like mastering an "etch a sketch". But my interest lead me here because I want to know. I wish I could meet someone that could traim me to use a lathe. I would learn for free in exchange to benfit the master on my spare time. This is some of the most interesting stuff I have ever come come by. My wanting for things to be precise, mechsnical inclination, my ridiculous attention to detail, and drive would come in handy. Time for another career change, what holds me back is that I do not have the freedom, nor can I afford to start off as a newbie. This is it though. I know it. *Typos
Good to see an instructional video with carbide threading inserts , only thing I would add is carbide inserts give a much better finish at higher speeds , something to work your way up to if you're disengaging the half nuts and you've got good hands.
Appreciate the comment. I was wondering how slowing the lathe way down was affecting the “speeds and feeds” equation. Presumably a high speed steel cutter would work better, perhaps with some tuning of the tool geometry? The trade-off is: if you don’t already have the tool in your inventory, you might spend more time grinding the tool than what it takes to make the part. In any event, the thread seems to be mechanically sound and passes the cost/benefit test. Comparing the final thread with one cut with a die would be an interesting exercise.
I got 11 cars and several motorbikes. I bought a lathe for this kind of projects. I remember the first time I cut a perfect thread. It was like I'd mastered witchcraft!
So THATS the part I forgot to do, been a while since I've run a lathe and I was running some practice passes a bit ago on some plastic and a few times I cut right through the high side of my threads, wasn't sure why, now I know, I got certified as a machinist when I was 16 and I'm 22 now so I've forgot quite a bit, tryina get back into it and you just solved my issue, I knew it had to be something simple, I just forgot to wait for the number to come around before I engaged the feed
Calculate the Undercut/Gutter diameter first using the thread tables book which tells you the approximate thread depth The nose width of the insert varies depending on the thread size AND Pitch (1.5 mm pitch in this case (OR Number of Threads per Inch) The Coarser the Thread, the bigger the Nose width Ideally required. So then you'll have to screw deeper on a Coarse thread if you only have a small nose width Insert. & a deeper undercut.
Good video editing. I also have a metric Harrison. For the thread you were cutting you can engage on any number every time. You seemed to use 8 the first time, then wait for 8 every time you re-engaged. You could re-engage on any number. Try some “air cuts” to prove it.
Thanks very much, glad you enjoyed it. For that thread your absolutely correct. I think I might have just reused the same bit of footage each time. Takes a lot time to set a shot up so reusing the footage saves a bit of time in production. Thanks for your support 👍
I bought a used Harrison AA. I took apart the cross slide dial assembly to clean and destroyed by mistake the 2-pin circular locking ring that holds things together. Tried to fashion a new one but cannot get the right size/pitch to go on smoothly. Any idea what those numbers could be?
Another great vid, thanks! now, I just need to work out a way to get a lathe up all those stairs into my flat :) Luckily, I've a great mate who lets me play around on his whenever I want, I just need to convince him he needs a mill, surface grinder and a shaper next, 👍
Just subscribed, recommended by my brother Carl Wilson. That was as good an explanation as I've seen on UA-cam. I like to make the gutter to the thread depth, that way when it scratches the gutter it's a good indication that you are pretty much at full depth. Tipped tooling is great because it gives you an indication when you get to the flats anyway. Great video. Dean in Oxfordshire.
When the thread chart says 1-8 you can engage the half nuts on any one of those numbers. You can also use a different number each time you engage the half nuts as well.
Would recommend using coolant when screw cutting you will get a much better finish, when I served my apprenticeship in the late 70s I ended up doing all the 2 and 4 start threads for the marine engineering company I worked for; that’s advanced screw cutting 😀
That was excellent, thanks, a very good explanation. That's my chosen method too. With inserts I think it's totally fine to go straight in with the cross slide and cut on both sides. These days I tend to keep the half nuts engaged, because I set my VFD up to have a fwd/rev switch for threading. I have programmed very fast deceleration times for the motor when run from that switch. It's a bit like having a clutch, as on the Harrison 140. I can stop dead, back the tool out and reverse the carriage. I need to make sure I cut a big enough drop out groove though, first! Thanks again, really enjoyed.
Cheers Carl, Great to hear from you again. Nice move with the VFD. Luckily I have a foot brake on mine if I need to stop it QUICK. Thanks again for the support. 👍
Excellent video demonstrating basic thread screw cutting and very well explained how you go about it and why you do things the way you do. Only difference in the way I do it is I turn the compound slide around to half the angle of the thread im cutting so that the depth of cut increase on the compound slide is following along the back edge of the thread and the tool is only ever cutting on the front edge, gives a nicer finish but is slightly more complicated for the lathe operator. As always learn to get he job done first then you can improve your skills and methods as experience increases.
It's well worth getting the full form inserts for whatever pitch you are threading, especially for common pitches such as 1.5mm. You can easily tell when you've cut the thread deep enough & you get a much nicer finish with no need to faff around with a file & Scotchbrite !
That insert is far too big for the pitch & will give a much larger radius in the root of the thread. So the cut had to be deeper to get the nut on that's why you machined into your undercut. This thread will not engage properly as the flanks have been machined too wide for the nut crest radius to clear the large root radius formed by using a tip that has a root radius form too large for the pitch. Also a full form insert will create the correct crest radius so no file or scotchbrite. The inserts are not designed to cut all around their profile so plunge cutting is not advised. Always advance the tool on the compound slide for each cut. You could have also increased the undercut with the threading tool.
I liked the way you explained the process at each step, but I'm not trying to teach you how to suck eggs, but when you're reengaging the thread cutter, after it's been moved, engage the drive as you would normally but keep the cutter off the job. Stop the Lathe with everything engaged and using the cross side move the cutting tool from left to right so it is in the correct position in relation to the thread. It will now be in the correct position to finish cutting the threads. I have also been told but haven't tried it yet, that if you can use the thread gauge to check the correct depth of the thread as well as the pitch. Great Video.
I'm glad that you mentioned the depth of cut, is 0.25mm good for all diameters/sizes of thread? How many advancements of 0.25 mm do you make, until you reach max depth? What's the maximum sticking out on the insert tool I guess? You can't cut any deeper than that.
Good video on thread cutting in the lathe. However sir please use some cutting oil or Anchorlube while performing this task. I read earlier in the comments you choose not too use it but if your teaching how to cut threads the correct way is too use cutting oil or some kinda lube. This keeps heat from building up and damaging your tool. Just a suggestion I think you done a great job on explaining the method.
Thanks, glad you enjoyed the video. I do use cutting oil normally, just not for the demo so people could see the tool a bit easier. Absolutely right about the oil and the heat it's a tool killer. Thanks for the support.
I have a lathe with an imperial lead thread so need to change gears to cut metric threads. I always cut straight in and much prefer to cut away from the chuck. I prefer to use HSS steel tools though I do have carbide inserted tools. I also have made an inside carbide tool for small inside threading. Well done video.
I said only one things: so said you THANK YOU for sharing us your work on a Lathe!!... God bless you and your families and friends in UK!!... best regards fron Santiago of Chile, SouthAmerica!!
Suggest you check Colchester training films on screw cutting. They show the topslide set over at half the thread angle. The cut is applied using the topslide with the cross-slide left at zero. So you are only cutting on one edge of the tool, the other side of the thread being generated by the top slide.
Nice job explaining what can be a very complex procedure. Also for showing the importance for learning the parts of the lathe. I might suggest for some that one way to speed up the process and to get very good results for the thread cut depth is to rough the thread to a size close and then run a thread die cutter over the rough cut thread to finish cut. That way you will have started the threads nice and straight as a lead for the thread die. Use the thicker thread cutting oil for a nice finish too. We used to do this because even a slight distance off on your depth can cause major problems either too tight or loose. Too deep and you made scrap. If you’re experienced enough you can place the thread cutter in the holder and let handle rotate up against the carriage. Turn the lathe on slow and stop the machine just before finishing the cut. Let the handle follow the carriage. Finish by hand and reverse the lathe holding the die cutter handle. This allows a straight precise thread every time that works. Most people can’t cut threads by hand without going crooked so they cut a rough thread and finish by hand. Brought back memories and using the thread gauge rods to measure groove depth. Learning how to read and find the information in a source book is a lesson in itself! Thanks for sharing
i always wondered how threads were lathed, and i never imagined for some reason they are just built into the machinery, as a function even on a manual one lol. for some reason i thought i was gonna be some etcha sketch magic with 2 knobs for feeding and cutting or something lol thanks for the vid. still crazy the manual timing amazing
Excellent thank you. Well explained, thank you for taking the time. Excellent camerawork too! Given me the confidence to have a go. I've subscribed, I'll check your other stuff later...🙂
I've never used a lathe but intend getting one which is why I watch things like this. Refitting the thread cutter accurately could cause problems. Surely best to leave it in place until you've finished (unless of course the groove is not deep enough). Couldn't you have continued and cut a shallow thread in the base of the groove and machined it out later for appearance? Really good instructive video, thanks.
With a quick change tool post the tool position repeatably is very good so that not a huge concern to be honest. Regarding cutting into the groove. That very much depends. If it is just a single pass then you could get away with it but if you had to keep making more cuts you need to stop the tool sooner each time or you can overload the tool and break it if it suddenly goes from the 3rd or 4th etc small cut into a piece of uncut material. The tool load suddenly shoots up and breaks the tip off. Hope that makes sense. Thanks for watching.
Nicely done, sir. Excellent organization, camera work, sound and editing. It is one thing to know how to do the operation and entirely another to be able to communicate it effectively. One thing this illustrates is the difference between a shop lathe and a small lathe like a Sherline that may have the lead screw gearing to cut threads but lacks refinements such as the dial.
Being a bike tech , I have say that is the weirdest front axle ever. By the way threads on bike axles are rolled not cut by single point threading. Rolled threads are used to give a cleaner thread with a controlled root radius.
Very nice little beginner tutorial. I would have liked you to show how to tell if the threads are deep enough without the nut to ensure all production nuts would fit on. I guess if I wanted I could get it close and then run a regular Die over the threads and that should do. Thanks for sharing. best Wishes & Blessings. Keith Noneya
Thanks for the feedback. Great idea about showing the measuring. A set of thread wires is the proper way to do it. Your absolutely right about the die technique, I sometimes do that myself on larger threads. Thanks for the support.
What you have to do Is never disengage the half nuts. If you do, since you don't have the indicator, you will loose your place and end up cutter a different thread each time. The way around this is to cut your thread, stop the machine, withdraw the tool, reverse the direction of the machine, drive it back to the start, change it back to running forwards, put on your next cut, start the machine, then do your next pass. Then repeat this process until your done. It take a fair bit longer as you have to wait for the machine to drive the saddle back to your start point, but works just as well. Remember once you have engaged the half nuts don't disengage them until your done. Best to practice on some scrap first. Dead easy once you get the hang of it. Hope this helps. Thanks for watching. 👍
Handmade Extreme can you skip withdrawing the tool (or only 1 thou back off) while reversing the lathe without a dial by putting reverse pressure on the hand wheel and “walking” the carriage back against the lead screw removing the backlash? I feel this may be a bit easier but I don’t know my southbend has a thread dial
Thank you for an excellent threading video, best I have seen. You mention an advanced method, but I cannot find it in your videos, am I missing something or is it work in progress?
Great video and explanation. 👍..... Served my time hand cutting threads like this but using the angled compound slide (half the angle of the thread) with hand ground has tools... I really do miss manual turning now I'm full CNC. . I would add, and by no means is it a criticism. Using a full form carbide insert as you are it's advantageous to leave the thread diameter slightly big (+0.2mm) so that when you get to full depth there is metal there for the tip to turn the rads on the peaks of the thread thus no need to dress the thread with a file. Also file away the thin parts of the first and last thread too.... 👍 Lovely vid tho'. Subscribed. 😁
Absolutely amazing video !!! Thanks for sharing and especially for throwing in the mistake because I make that mistake all the time !! Liked and subscribed
When I have done my initial scratch pass and I want to keep increasing the depth of cut till I reach the desired depth , do I use the cross slide to move in at 90 deg or do I use the compound slide to move in at 29 deg ?
Either way works. A lot of people say the cross slide method is easier. I prefer to use the compound as you can set a zero on your cross slide that you return to on every pass, and just feed in your compound. I will say, you get a better finish with the compound method as all the tool force is in one direction.
...Undercut... That's the one..😁 I normally do but for some reason I went a bit shallow. Finger trouble, number trouble, general incompetence... who knows haha Thankfully it turned into a nice opportunity to demonstrate the advantage of this method over the drive it back and forwards one. Regarding coolant, normally i'd use some cutting oil but left it out for the video just so it's a bit clearer for people to see whats going on but your absolutely right! Thanks for the support and i'm glad you enjoyed it. 👍
Thanks, this is like having a virtual 'over the shoulder' look within a machine shop - I have a small imperial Holbrook I acquired from my old Chemistry teacher's dad who was an RAF mechanic and then a technology teacher before he suffered from health problems and had to have his basement workshop cleared out - there are so many bits he had made for it I have no clue what many of them do as they only taught us basics at school - I would love to be able to use the thread cutting feature but am too scared I'll mangle the whole lathe doing so!
Problem is cutting a thread with that tool tends to churn up the thread as it doesn't have much of a top or side rake. When I was cutting threads on mild steels on conventional lathes preferred to use hand ground HSS tools. A quick way to cut that thread is to turn the top slide to half the thread included angle and feed in with it. To finish use both sides of the tool to fine finish. Ok to truncate the thread with a file but radius it as you go. If you have a thread comb and toolpost rest all the better.
Very interesting to see the multiple gears at the bottom of the lead screw dial - most second hand machines don't have any more than the one gear left!! Then your only option is to leave the nut engaged !
It is more imortant that you are taking the time to show someone how to do something . Good on ya mate
Nicely done sir. In the early 80's I was fortunate enough to have my employer fund a full 5 year mechanical engineering apprenticeship. This Brough back happy memories. Excellently and precisely explained.
Thank you. I'm glad you enjoyed it. I too was lucky to be in a similar situation where my employer at the time put me through college. On the job training or 'learn as you earn' is a great way to gain both knowledge and experience in my opinion.
This is the method I have learned on the manual lathes. and always used. I used to make spindles for axles on semi tractors and stuff. Then I went to school for CNC and was smitten. Thank you for explaining this so well
Your welcome. Glad you enjoyed it.
My father used to do a 14 feet long shaft with ease.
I was about 11 or 12 years old maybe. He was a great turner. Passed away in 2012.
Wish he was alive to teach me all this stuff.
Superb video mate,& demystified manual threading massively for me- been having to use retention screws instead of threaded parts on my hobby project due to lack of time to get trained up,& this has given me a mental grounding in the process to get started threading future builds.Brilliantly clear explanation- much obliged,sir!
This is a good, thorough, tutorial covering ALL steps in setting up the machine. I would offer to immediate improvements to ending up with a better thread. The first being a faster spindle RPM. It appeared the RPM chosen was simply the slowest ...which is fine. But the problem is this cutting speed is in fact very slow ....on purpose.
1) A faster CS would automatically provide a better finish on the thread form. But this is up to the operator and their comfort zone with operating the half-nut disengagement only, for this one example. As determined and explained, for this thread pitch, any of the 8 engagements on the thread dial indicator will keep the pitch ...so there is no challenge factor in engaging ....and this engagement can be as far away from the thread start point aw the operator chooses. It is the "disengagement" that is the critical point ....but this is also dependent on how wide the relief is. Nothing wrong with practicing this technique. It just requires concentration.
2) The depth of cut chosen was very deep on the second pass. Considering the extremely low RPM, this resulted in extremely poor surface finish because the metal was literally tearing off the parent material ....and the surface finish looked awful. The depth extreme depth of cut can be taken, but it need NOT be that deep. As the final thread depth of cut is approached, the actual cutting depth should be reduced, simply because there is more material being removed at the deeper cuts.
3) And lastly, it is very common practice to run at least one "extra" pass after the last finish depth has been reached. Even though this bar is supported on a center, the bar material still deflects. There was a lot of tool pressure still on the last cut. A "cleanup" cut just makes sense to perform. It will literally always improve the thread surface finish as well .....which is what the female thread is going to be running on.
There wasn't very much offered about "fitting" the thread and the testing of the nut did not reveal very much either nor was there any mention about the fit/class .....but considering this was only a tutorial using the cross-slide, ....enough said.
That was a brilliant lesson on thread cutting. I'm a very keen hobbyist and self taught. Your lesson has taken away most of the scary stuff for me. Thank you very much
Glad it was helpful. Good luck with your own projects. 👍
That's how I learned it during my apprenticeship but we also rotate the toolpost. Very good tutorial!
When I started my apprenticeship, I was taught how to calculate the thread depth (using simple mathematics). The second thing I learned is that when you did the final cut and the nut fits perfectly, NEVER to use a file on the thread or "scotch brite". The thread should be smooth and shiny. In this video, you can see on the "chip" that there is chatter. However, a good tutorial for a beginner !
Yeah, this video is pretty scary to watch. He's going way too slow to get a good finish and I don't understand why you wouldn't turn the compound to decrease chatter.
Could you share the info on how to calculate the thread depth?
@@spazzwazzle he said that there are better ways to do the job ...but this is a fairly basic method with less chance to make mistakes... i am sure he could do if he wanted to
Excellent, concise and honest presentation. No verbal diarrhea ... just tell it as it is. Well done ... thanks.
Your welcome, thank you. Glad you enjoyed it. 👍
Many of your viewers (me, for instance), have less rigid lathes. If I try to plunge-cut a 1.5mm thread on my seventy year old Myford Super 7, I will end up with a lifetime supply of chatter marks!
For lesser beings like us, the 29.5 degree compound slide method is our saviour! Sadly for me, my lathe is also short of its thread-cutting dial... My father bought the lathe when I was five years old, and gave it to me thirty years later, so I know it did not ever have a dial... might be a project for me. 😜
Great video, thank you. It did drive me la-la though; your voice is very familiar, but I could not figure out why! 🥴
As an afterthought... because the Myford has a clutch, I can make a cutting pass, disengage the clutch and withdraw the tool, then wind the carriage back using the handwheel on the leadscrew. This is actually a very quick process, and works great with the 29.5 degree compound, and no threading dial... it's also pretty foolproof. 😛
Excellent video!! I have seen dozens and dozens of videos of thread cutting. This one is by far the best and most well explained!
Thank you. Glad you enjoyed it.
My two cents worth……..engaging and disengaging the half nut lever is only done when you are cutting very long threads. With most typical threads such as this you simply withdraw the tool quickly at the end of cut and put the machine into reverse to get back to your start.
I agree. Where you disengage and engage the half nut, it doesn’t always go back exactly the same. Especially with an older lathe. You can easily cut the thread too deep or too wide usually when doing final cuts.
Great if you can reverse!
Flip the tool upside down, and start the tool from the chuck side and feed toward the tailstock and run the lathe in reverse. Learned this from the best toolmaker I have ever know who was from Germany. Many advantages, the most important is that the chips fall down out of the groove instead of bouncing around in the groove and ruining the finish. Running off the part at the end is more forgiving and gives you more time to disengage the half nut, therefore you can run the rpm higher for smaller diameters. And no, you won't cut a left hand thread this way.
Dude, you dont even know that you saved my sorry ass right now, thanks😁
A great method as long as the chuck doesn't unscrew and follow the chips into the chip tray. Make sure the chuck is locked onto the spindle thread. 🙂
This is also a better method for parting off.
But don't do this for any heavy turning op's as the force is not directed down into the machine.
Great video .. in my school days we did so much theory on how lathes worked and then never got to use one.. now I'm at an age I can maybe buy my own and learn.
You just earned a subscriber. Just started to look for a metal lathe and gathering some information on various techniques and this one is very concise. Excellent job !!!!
This is the method I learned in school, great job at making info more accessible.
Glad it was helpful! Thank you.
Just found your channel as I've upgraded to an M300 from a Myford and liked your RPC video.
If you're just doing a simple "plunge cut" threading job and you have the nut handy for sizing, advance the top slide a couple of thou every cut, this mimics the angled top slide method and let's the tool cut primarily on its leading edge, reducing tip loading and generally provides a smoother finish to the threads.
Nice idea. I'll have to give that a try some time. Thanks for the support.
Nice video for demonstrating cutting metric threads, may also add depending on what brand of lathe swapping gears to do metric or atandard threads. Ive been cutting threads on old school lathes for 35 years myself,over all great video
I was taught to turn tool upside down, run lathe in reverse, and cut from chuck towards tailstock. This reduces the risk of a crash into the shoulder, and no need for a large undercut. I always cut threads this way, and have done for last forty-five years, unless using an Ainjest attachment.
Martin 1299S: that is a good method if you have a good lathe, but it does tend to be lifting the toolpost off the bed, rather that pushing it down.
That lathe is wicked upscale compared to either of my lathes.
Dude this is so great. I have always wondered how this worked. Because I have seen loads of videos where the camers is focused on the cut while threading but with no explaination. I just assumed the person using the machine practiced their timing enough that they were just that good. I am not ignorant enough to assume it was like mastering an "etch a sketch". But my interest lead me here because I want to know. I wish I could meet someone that could traim me to use a lathe. I would learn for free in exchange to benfit the master on my spare time. This is some of the most interesting stuff I have ever come come by. My wanting for things to be precise, mechsnical inclination, my ridiculous attention to detail, and drive would come in handy. Time for another career change, what holds me back is that I do not have the freedom, nor can I afford to start off as a newbie. This is it though. I know it.
*Typos
Good to see an instructional video with carbide threading inserts , only thing I would add is carbide inserts give a much better finish at higher speeds , something to work your way up to if you're disengaging the half nuts and you've got good hands.
Absolutely right. Got to have quick hands when doing it manually at the higher speeds.
Appreciate the comment. I was wondering how slowing the lathe way down was affecting the “speeds and feeds” equation. Presumably a high speed steel cutter would work better, perhaps with some tuning of the tool geometry? The trade-off is: if you don’t already have the tool in your inventory, you might spend more time grinding the tool than what it takes to make the part.
In any event, the thread seems to be mechanically sound and passes the cost/benefit test. Comparing the final thread with one cut with a die would be an interesting exercise.
I got 11 cars and several motorbikes. I bought a lathe for this kind of projects.
I remember the first time I cut a perfect thread. It was like I'd mastered witchcraft!
This is the way all 'how-to' videos ought to be made - concise, but still quite instructive. Very well done indeed - thank you!
So THATS the part I forgot to do, been a while since I've run a lathe and I was running some practice passes a bit ago on some plastic and a few times I cut right through the high side of my threads, wasn't sure why, now I know, I got certified as a machinist when I was 16 and I'm 22 now so I've forgot quite a bit, tryina get back into it and you just solved my issue, I knew it had to be something simple, I just forgot to wait for the number to come around before I engaged the feed
Calculate the Undercut/Gutter diameter first using the thread tables book which tells you the approximate thread depth The nose width of the insert varies depending on the thread size AND Pitch (1.5 mm pitch in this case (OR Number of Threads per Inch) The Coarser the Thread, the bigger the Nose width Ideally required. So then you'll have to screw deeper on a Coarse thread if you only have a small nose width Insert. & a deeper undercut.
Machinerys handbook is key. Calculating minor and major diameter are also key, you're right.
Good video editing. I also have a metric Harrison. For the thread you were cutting you can engage on any number every time. You seemed to use 8 the first time, then wait for 8 every time you re-engaged. You could re-engage on any number. Try some “air cuts” to prove it.
Thanks very much, glad you enjoyed it. For that thread your absolutely correct. I think I might have just reused the same bit of footage each time. Takes a lot time to set a shot up so reusing the footage saves a bit of time in production.
Thanks for your support 👍
I bought a used Harrison AA. I took apart the cross slide dial assembly to clean and destroyed by mistake the 2-pin circular locking ring that holds things together. Tried to fashion a new one but cannot get the right size/pitch to go on smoothly. Any idea what those numbers could be?
Another great vid, thanks! now, I just need to work out a way to get a lathe up all those stairs into my flat :) Luckily, I've a great mate who lets me play around on his whenever I want, I just need to convince him he needs a mill, surface grinder and a shaper next, 👍
Hahaha better buy him a few bears. Glad you enjoyed it and thanks for the support.
I can see why this is the last thing we're going to learn on a manual lathe at school. 😅Everything else has been pretty simple comparatively.
Just subscribed, recommended by my brother Carl Wilson. That was as good an explanation as I've seen on UA-cam. I like to make the gutter to the thread depth, that way when it scratches the gutter it's a good indication that you are pretty much at full depth. Tipped tooling is great because it gives you an indication when you get to the flats anyway. Great video. Dean in Oxfordshire.
Ahh, another Wilson. Welcome to the channel it's great to have you here. I'm glad you enjoyed the video and thanks for the tip 👍
When the thread chart says 1-8 you can engage the half nuts on any one of those numbers. You can also use a different number each time you engage the half nuts as well.
Dude that was awesome 👏
Thank you for sharing this
Glad you enjoyed it! Thanks.
Would recommend using coolant when screw cutting you will get a much better finish, when I served my apprenticeship in the late 70s I ended up doing all the 2 and 4 start threads for the marine engineering company I worked for; that’s advanced screw cutting 😀
i have a m300 lathe and ive learnt soooo muchhhh from this video
That was excellent, thanks, a very good explanation. That's my chosen method too. With inserts I think it's totally fine to go straight in with the cross slide and cut on both sides. These days I tend to keep the half nuts engaged, because I set my VFD up to have a fwd/rev switch for threading. I have programmed very fast deceleration times for the motor when run from that switch. It's a bit like having a clutch, as on the Harrison 140. I can stop dead, back the tool out and reverse the carriage. I need to make sure I cut a big enough drop out groove though, first!
Thanks again, really enjoyed.
Cheers Carl,
Great to hear from you again. Nice move with the VFD. Luckily I have a foot brake on mine if I need to stop it QUICK.
Thanks again for the support. 👍
@@Handmadeextreme No problem. You have a great lathe. Very useful tool. I'm looking forward to the next video about the car too.
I don't have a lathe and I found this very interesting. Thank you
Excellent video demonstrating basic thread screw cutting and very well explained how you go about it and why you do things the way you do. Only difference in the way I do it is I turn the compound slide around to half the angle of the thread im cutting so that the depth of cut increase on the compound slide is following along the back edge of the thread and the tool is only ever cutting on the front edge, gives a nicer finish but is slightly more complicated for the lathe operator. As always learn to get he job done first then you can improve your skills and methods as experience increases.
It's well worth getting the full form inserts for whatever pitch you are threading, especially for common pitches such as 1.5mm. You can easily tell when you've cut the thread deep enough & you get a much nicer finish with no need to faff around with a file & Scotchbrite !
I'll check them out, thanks for the tip. 👍
That insert is far too big for the pitch & will give a much larger radius in the root of the thread. So the cut had to be deeper to get the nut on that's why you machined into your undercut. This thread will not engage properly as the flanks have been machined too wide for the nut crest radius to clear the large root radius formed by using a tip that has a root radius form too large for the pitch. Also a full form insert will create the correct crest radius so no file or scotchbrite. The inserts are not designed to cut all around their profile so plunge cutting is not advised. Always advance the tool on the compound slide for each cut. You could have also increased the undercut with the threading tool.
Thank you I just bought a lathe without a compound slide, only a tool holder on the cross slide, I think I can cut threads with it now.
Excellent post.. straight to the point with no excessive verbal chatter (:0)
I liked the way you explained the process at each step, but I'm not trying to teach you how to suck eggs, but when you're reengaging the thread cutter, after it's been moved, engage the drive as you would normally but keep the cutter off the job. Stop the Lathe with everything engaged and using the cross side move the cutting tool from left to right so it is in the correct position in relation to the thread. It will now be in the correct position to finish cutting the threads. I have also been told but haven't tried it yet, that if you can use the thread gauge to check the correct depth of the thread as well as the pitch. Great Video.
Great video mate! I came originally for the transit caliper rebuild but now I’m fascinated!! Cheers
Thank you for the support. Glad you are enjoying the channel.
NIce lathe, good tooling, good job, good worker and excellent teacher. Thank you 😊
I'm glad that you mentioned the depth of cut, is 0.25mm good for all diameters/sizes of thread?
How many advancements of 0.25 mm do you make, until you reach max depth? What's the maximum sticking out on the insert tool I guess? You can't cut any deeper than that.
Love your cnc X and Z axis references on a manual lathe.
Cheers, Glad you enjoyed it.
Manual machines have the Axis as well
Good video on thread cutting in the lathe. However sir please use some cutting oil or Anchorlube while performing this task. I read earlier in the comments you choose not too use it but if your teaching how to cut threads the correct way is too use cutting oil or some kinda lube. This keeps heat from building up and damaging your tool. Just a suggestion I think you done a great job on explaining the method.
Thanks, glad you enjoyed the video. I do use cutting oil normally, just not for the demo so people could see the tool a bit easier. Absolutely right about the oil and the heat it's a tool killer. Thanks for the support.
I have a lathe with an imperial lead thread so need to change gears to cut metric threads. I always cut straight in and much prefer to cut away from the chuck. I prefer to use HSS steel tools though I do have carbide inserted tools. I also have made an inside carbide tool for small inside threading. Well done video.
I said only one things: so said you THANK YOU for sharing us your work on a Lathe!!... God bless you and your families and friends in UK!!... best regards fron Santiago of Chile, SouthAmerica!!
Absolutely awesome vid! Much respect and gratitude from New York
Thanks, glad you enjoyed it.
Suggest you check Colchester training films on screw cutting. They show the topslide set over at half the thread angle. The cut is applied using the topslide with the cross-slide left at zero.
So you are only cutting on one edge of the tool, the other side of the thread being generated by the top slide.
thanks for sharing this method.
I will check it out on my kather when it arrives.
Nice job explaining what can be a very complex procedure. Also for showing the importance for learning the parts of the lathe.
I might suggest for some that one way to speed up the process and to get very good results for the thread cut depth is to rough the thread to a size close and then run a thread die cutter over the rough cut thread to finish cut. That way you will have started the threads nice and straight as a lead for the thread die. Use the thicker thread cutting oil for a nice finish too.
We used to do this because even a slight distance off on your depth can cause major problems either too tight or loose. Too deep and you made scrap.
If you’re experienced enough you can place the thread cutter in the holder and let handle rotate up against the carriage. Turn the lathe on slow and stop the machine just before finishing the cut. Let the handle follow the carriage. Finish by hand and reverse the lathe holding the die cutter handle.
This allows a straight precise thread every time that works. Most people can’t cut threads by hand without going crooked so they cut a rough thread and finish by hand.
Brought back memories and using the thread gauge rods to measure groove depth. Learning how to read and find the information in a source book is a lesson in itself!
Thanks for sharing
Great explanation there that gets straight to the point.Well done.
Thank you.
i always wondered how threads were lathed, and i never imagined for some reason they are just built into the machinery, as a function even on a manual one lol. for some reason i thought i was gonna be some etcha sketch magic with 2 knobs for feeding and cutting or something lol thanks for the vid. still crazy the manual timing amazing
Excellent thank you. Well explained, thank you for taking the time. Excellent camerawork too! Given me the confidence to have a go. I've subscribed, I'll check your other stuff later...🙂
I've never used a lathe but intend getting one which is why I watch things like this.
Refitting the thread cutter accurately could cause problems. Surely best to leave it in place until you've finished (unless of course the groove is not deep enough).
Couldn't you have continued and cut a shallow thread in the base of the groove and machined it out later for appearance?
Really good instructive video, thanks.
With a quick change tool post the tool position repeatably is very good so that not a huge concern to be honest. Regarding cutting into the groove. That very much depends. If it is just a single pass then you could get away with it but if you had to keep making more cuts you need to stop the tool sooner each time or you can overload the tool and break it if it suddenly goes from the 3rd or 4th etc small cut into a piece of uncut material. The tool load suddenly shoots up and breaks the tip off. Hope that makes sense. Thanks for watching.
@@Handmadeextreme Thanks. Now to find a decent lathe!
Nicely done, sir. Excellent organization, camera work, sound and editing. It is one thing to know how to do the operation and entirely another to be able to communicate it effectively.
One thing this illustrates is the difference between a shop lathe and a small lathe like a Sherline that may have the lead screw gearing to cut threads but lacks refinements such as the dial.
Being a bike tech , I have say that is the weirdest front axle ever. By the way threads on bike axles are rolled not cut by single point threading. Rolled threads are used to give a cleaner thread with a controlled root radius.
Very nice little beginner tutorial. I would have liked you to show how to tell if the threads are deep enough without the nut to ensure all production nuts would fit on. I guess if I wanted I could get it close and then run a regular Die over the threads and that should do. Thanks for sharing. best Wishes & Blessings. Keith Noneya
Thanks for the feedback. Great idea about showing the measuring. A set of thread wires is the proper way to do it. Your absolutely right about the die technique, I sometimes do that myself on larger threads. Thanks for the support.
My lathe was built before threads were invented .... if I win the lottery I will upgrade ! ( some nice tip in that vid such as highlighting the part )
Nicely done. I like to gently run a small 60degree file along the thread to give a nice clean thread.
Phwoooooaaaar! That's some good lathe operation!
Haha, thanks glad you enjoyed it.
Im about to start working on one of those, i have basic knowledge but it would be great if you had a video explaining every feature of the machine
Not sure why I'm watching this now, I don't even own a lathe yet lol. But maybe some of this info will stick for when I need it, thanks!
Funny this should come up. I have a Myford ML7 and I was doing an internal acme thread yesterday. It's a bit of a challenge.
Great video! I really appreciate the detail you used.
Excellent video, it's very well explained and filmed. Thank you so much to you.
Glad it was helpful!
You forgot to use pitch guage for setting up the toolbit to make sure it aligned in the center
Teach me how
Brilliant Video for learners.
I'll probably never be able to afford one of those lathes, but I still found this interesting.
I doing this from last 10 years in Singapore. And i love to make it
Great video, one of the best I've seen on cutting a thread.
If I don't have a thread dial indicator, how do I go about this?
What you have to do Is never disengage the half nuts. If you do, since you don't have the indicator, you will loose your place and end up cutter a different thread each time. The way around this is to cut your thread, stop the machine, withdraw the tool, reverse the direction of the machine, drive it back to the start, change it back to running forwards, put on your next cut, start the machine, then do your next pass. Then repeat this process until your done. It take a fair bit longer as you have to wait for the machine to drive the saddle back to your start point, but works just as well. Remember once you have engaged the half nuts don't disengage them until your done. Best to practice on some scrap first. Dead easy once you get the hang of it. Hope this helps. Thanks for watching. 👍
Handmade Extreme can you skip withdrawing the tool (or only 1 thou back off) while reversing the lathe without a dial by putting reverse pressure on the hand wheel and “walking” the carriage back against the lead screw removing the backlash? I feel this may be a bit easier but I don’t know my southbend has a thread dial
This is great info! Thanks very much for the demo!!
Thank you for an excellent threading video, best I have seen. You mention an advanced method, but I cannot find it in your videos, am I missing something or is it work in progress?
Great video and explanation. 👍..... Served my time hand cutting threads like this but using the angled compound slide (half the angle of the thread) with hand ground has tools... I really do miss manual turning now I'm full CNC. .
I would add, and by no means is it a criticism. Using a full form carbide insert as you are it's advantageous to leave the thread diameter slightly big (+0.2mm) so that when you get to full depth there is metal there for the tip to turn the rads on the peaks of the thread thus no need to dress the thread with a file.
Also file away the thin parts of the first and last thread too.... 👍
Lovely vid tho'. Subscribed. 😁
Just found your video good quality all round & the lathe it speaks for its self, just subscribed, Coventry Uk 🇬🇧👍.
Welcome to the party, great to have you here. Glad you enjoyed the video and thanks for the support.
That's ok. Best to run in CCW thread from left to right. Use a hard saddle stop or DRO for Z0.
Absolutely amazing video !!! Thanks for sharing and especially for throwing in the mistake because I make that mistake all the time !! Liked and subscribed
Glad you enjoyed it. Welcome to the channel.
Hope everyone is learning as much as I have from this. In a gunsmithing course right now. Helped out a lot. Take it easy my "Niggels" 😂😂
You are really unique, thank you for your efforts, it was great.🙏🙏🌹🌹
Thanks for showing great tutorial ,nice and simple
Good tutorial video. I used that exact machine , I always use the reverse Chuck method, never use the 1_8 dial.
Glad you found it useful. It's a great machine isn't it! Thanks for watching.
Give the dial a go.Its a good way to go.Ive just learned how on my old machine.
@@derekcollins1972 I have used the dial over the decades and also used the Ainjest quick screw attachment but I prefer the reverse method.
Καλό και εκπαιδευτικό το βίντεο. Μπράβο!!!!
Sangat luar biasa
Very concise explanation, cheers!
I have the same lathe. Can I use my carriage stop to cut the exact length of thread I need?
When I have done my initial scratch pass and I want to keep increasing the depth of cut till I reach the desired depth , do I use the cross slide to move in at 90 deg or do I use the compound slide to move in at 29 deg ?
Either way works. A lot of people say the cross slide method is easier. I prefer to use the compound as you can set a zero on your cross slide that you return to on every pass, and just feed in your compound. I will say, you get a better finish with the compound method as all the tool force is in one direction.
Love the term Gutter used for UNDERCUT. Machine the undercut to the thread root dia. also use a bit of coolant. Great video well explained.
...Undercut... That's the one..😁 I normally do but for some reason I went a bit shallow. Finger trouble, number trouble, general incompetence... who knows haha Thankfully it turned into a nice opportunity to demonstrate the advantage of this method over the drive it back and forwards one. Regarding coolant, normally i'd use some cutting oil but left it out for the video just so it's a bit clearer for people to see whats going on but your absolutely right!
Thanks for the support and i'm glad you enjoyed it. 👍
@@Handmadeextreme blame it on concentrating on the filming.
Amazing video, really loved it!
Comprehensive and clear. Thank you.
Hi.Would it also be possible to just pick a number on the dial,and stick with it?
Exellent video sir, very useful for us. You told some of tricks.Thank you so much sir.
Thanks, this is like having a virtual 'over the shoulder' look within a machine shop - I have a small imperial Holbrook I acquired from my old Chemistry teacher's dad who was an RAF mechanic and then a technology teacher before he suffered from health problems and had to have his basement workshop cleared out - there are so many bits he had made for it I have no clue what many of them do as they only taught us basics at school - I would love to be able to use the thread cutting feature but am too scared I'll mangle the whole lathe doing so!
Amazing tutorial, so informative, thank you!
Great video explaining this process. Thanks.
Always wondered how this was done. Thank you!
Problem is cutting a thread with that tool tends to churn up the thread as it doesn't have much of a top or side rake. When I was cutting threads on mild steels on conventional lathes preferred to use hand ground HSS tools. A quick way to cut that thread is to turn the top slide to half the thread included angle and feed in with it. To finish use both sides of the tool to fine finish. Ok to truncate the thread with a file but radius it as you go. If you have a thread comb and toolpost rest all the better.
Very interesting to see the multiple gears at the bottom of the lead screw dial - most second hand machines don't have any more than the one gear left!! Then your only option is to leave the nut engaged !
Nice video shot, keep it up, thanks for sharing it :)
Great video! Really easy to understand the process. Right where are my workshop keys to go and give that a go! 😃
Hi Josh,
I'm glad you found it useful. Good luck in the workshop and thanks for the support!