I've been running a mill and a lathe for about 40 years and can do setups in my sleep (not really), but explaining what and how to do it like Mr. Rucker can is an art unto itself. I know I couldn't do it, kudos to a good teacher!
When making a non-standard thread I always make the nut first. It is a lot easier to test the fit using the nut than trying to test the internal thread using the shaft. Also using standard thread with an easily obtainable nut would make it easier for later repairs if necessary. But I must add this was a fantastic tutorial on thread cutting.
I agree. He should have made the nut first, especially since it’s non standard left hand to be fitted to the long heavy shaft. It will be interesting to see how he does that. I’m guessing he’ll need to machine a short shaft with L.H. threads to use as a thread gage.
@@ellieprice363 Yes, a short thread gage for the nut. Now you can make a spec nut. But the shaft will be in spec too because it gets measured directly. So no need for the nut except for the satisfaction of screwing it on. Unless you want a nut that has minimum clearance (like a thou or two instead of .003/.007 probably, just guessing). A tight custom fit is nice.
Thanks for taking the time from your busy life to share this knowledge with the rest of us. Oh where were you when I was taking the first year of college machine shop. I've learned so much more from you, Keith F, Adam, Brian, Dave R, at old time steam, and Curtis with Cutting Edge Machinery in Australia, and his dog Homey, and so many more.
Thank you for sharing. Thank you for showing the step by step on cutting left-hand threads, watched and as always enjoyed it. Keep up your dedication to your RU-vid channel have learned and enjoyed your channel for many years. Gary👍
Happy new year! I find this channel to be inspiering and interesting even though I am a wood worker by trade. Good craftsmanship is universal. Someone would benefit from being your - apprentice.
Nice job.. I bought a 9"A benctop and I love it! I am also working on decruding an early 40's 16" tool room South Bend. I can't wait to get it all cleaned up and back in service.
Great teaching video! Gave instructions for the person who's never cut a thread before, but threw in a couple of nuggets for the more experienced people!
Thanks Keith for the left hand threading lesson, excellent job as always. I really enjoyed all the different camera angles, that really helps in understanding all the steps and what you’re actually doing with your hands during those steps. This video would be a great primer for anyone who wants to learn cutting threads, either left hand or right hand threads. Thanks for leaving in the part where your halfnut doesn’t engage perfectly, I was just wondering what you’d do if it didn’t engage right. So thanks for leaving that in. Wishing you and yours and everyone else a Happy New Years!
Much the best tutorial on thread-cutting I've seen yet. The thread dial was the missing link for me personally - no-one seems to cover this. Simple and obvious when you know how, but baffling for a beginner to hear people refer to a 'dial' and a 'number' without ever putting it in context or showing you what they're talking about. I now feel confident enough to actually try it myself - thank you!
Great lesson in threading Keith, when this is project is completed and time goes by (40-50 years) and were not around to warn the next person that takes this machine apart,...would it be appropriate to stamp LH on the end of the shaft?
Left handed nuts usually have a groove cut in them do indicate that, just look at your oxy set, fuel gas is left handed. I have seen mechanics tricked by left handed threads on wheel nuts on left side of trucks.
Definitely easier for everyone to label it. However I always try to check the angle of the threads when dissembling rotating parts if there is one thread you can see. Down to left or right. Has saved me before,lol.
@@ThAtGuY-u9d If all nuts were undone by engineers, not such a problem. If turning a nut doesn't loosen it but tightens it, it's a sure sign of a left hand thread. You just need a sensitive enough feel to detect that.
Great video. It brought me back to the mid 1980’s when I used to have an old 21” Monarch. The most stressful work that I did on that lathe was doing 3-1/2 inch internal Acme thread at 4 threads per inch. You really have to watch carefully then disengage the screw, and move the carriage forward a couple of turns simultaneously. All very nerve racking at the speed needed to get good results in aluminum. I don’t miss that much but enjoy seeing you working and explaining to us how and why you are doing it. Thanks.
I really appreciate how good of a problem solver Keith is. I feel like I learn as much about metal turning as I do how to think through out a challenge.
Pitch dia. for 1 1/4-10 2a fit is 1.184max to1.177min rounded up which i do to be safe in tolerance. Since you are making the nut and it is not standard going to the other shaft and getting your measurement works too. Have to agree with others that the nut should have come first. To each their own and it will workout either way.
Quite a nice introduction. The debate about 30deg, 29.6deg, or straight in goes on and on. The best argument I have heard for 29.5 over 30 is that it insures both thread flanks are smooth in a world with inevitable errors in the tool angle, compound angle, tool setup, and so on. A few minutes here and there should be less than the 0.5 degree. The internal stop for threading is so nice. I miss my old lathe that had it (Pacemaker), so I made a drawscrew type for my current lathe (better than the clamp type that grabs the cross slide ways, in my opinion)
It doesn't go on in the machine shops I have worked in, never seen anyone angle the compound to cut a thread besides on RU-vid, at trade school the teacher told us about it but never did it. You can work out the ratio to move the compound to keep it cutting on one side or after a few hundred threads you just wing it like every machinist I know does. The reasons I don't angle the compound is that you can't just work out the depth and go straight to it, for large threads you can't clean up both sides and if you're using the compound for widths or lengths you would have to move the compound every job. For a hobbyist it isn't even something to argue about, the end result is the only thing that matters, not efficiency, so whatever works for you.
You can put slight pressure on the threading lever just before the number you want to engage on and the carriage will slide into engagement of the feed screw. No need to worry about missing a number or slamming into engagement. Thanks for the vid!
Keith, I think that I agree with several other commenters about marking the end of this thread as "LH" or similar. However, I _really_ wish that you had modified that cutoff tool to have had (honed) radii to avoid leaving stress risers in the new shaft for future owners to deal with. I'm certain that such a tool would come in handy in future jobs in your shop!
Thanks Keith for another very informative video. Hope you had a great Christmas, and from mine to yours and all your watchers and subscribers, a very, happy, safe and prosperous 2022. J.C Liverpool, UK
Keith, this is one of my favorite videos of yours! Threading thoroughly explained with great camera work. Have a great 2022. Best wishes to you and all your family.
Thanks for the details, Keith. I'm new at learning to use a metal lathe (a cheap, little-bitty hobbyist bench lathe, but a lathe none the less) and this helps me understand it tremendously. Keep up the good work.
Hi Kieth. I just found your channel a short time ago. I know nothing about what you do but I've found this subject both educational and entertaining. I subscribed and am looking forward to new videos as well as checking out your older stuff.
Hi Keith, enjoyed your videos on cutting the taper and the left hand thread. I used to work a Holbrook lathe which had advantages over your lathe for both of these jobs. It had a double cross slide. When taper turning the normal cross slide indeed was still available. There was a quick cam out lever so you could thread to a point or shoulder by coordinating the movement of your right and left hands on the cam out lever and the half nut lever.
In high school we feed on the cross side only. The problem with that as you said you're cutting on both sides of the tool and you have twice as much surface touching. It doesn't cut as smooth and your much more likely to chatter. It wasn't till I was out of school I learned the method you used. My machiest hand book has a chart that shows both the cross feed number and for the compound method. The common thread pitch gage has the double depth number for the cross feed depth. There is a formula for converting that number for the compound method. I like to use the nut that is going to be used but you didn't have that. Another way to check is by using thread wires but are tricky to hold properly. Your thread is the way to go. Very nice job the way. In high school all our lathes had quick change gear boxes so I got spoiled from the start. Change gears will do just as good a job but the time get them setup . And you have a stack of gears to put away somewhere.
Thanks for taking the time to show all the details this video covers. I know you could have done that work in half the time of less without having to move the camera and do the commentary, not to mention the post-production work. Thanks as always for being a teacher! And, of course, Happy New Year!
I was taught to do the undercut first leaving it 5 thou over core/root diameter. Then you can keep cutting until you just witness onto the undercut then do your measurements and final fine cuts. Afterward go back and take the undercut a little under core/root.
