Not criticising your technique as I've wrestled with setting the 29-29.5 degree compound angle and my compound has heaps of backlash, so this technique is a gift. Not trying to be picky, given that you're using 20 thou DOC on each pass, if you go to 11 thou on the compound to every 20 thou on the cross slide you'd be hitting 28.8 degrees. Great video and HUGE thank you Subscribed.
I suffered under the tutelage of an old German machinist, and at the same time I was taking machine shop in high school. Klaus, always used the method you just presented, so I dared not do anything else in his shop. My High school teacher always had us set the compound at 29 1/2 degrees. Neither man ever explained just why that threading was done the way it was. Both methods worked just fine for me, and I was never questioned by any one in the companies I worked for. ( I think I was the only kid who was trusted to cut threads on valuable work pieces) At University, the machine shop teacher noticed me using your described method, and muttered something about a " Bad European influence" that I never understood. But again, I always got to thread the more important projects we built for the school. It was only a few years ago, after watching lots of different people cutting threads, on RUclips, that I did notice the difference in compound settings, And sure enough European, and Common Wealth machinist used your compound set at 90 degrees. Previously I had only cut multi lead threads, by using the compound set as you have shown. I liked that method, as I could always fudge a bit and always got a perfect fit, something that was not always easy to obtain. I used to think I was a pretty great machinist, but after watching some of the folks on RUclips, I look like a rank armature, even after almost 60 years of working in machine shops, including mine!!! So, I'm an old dog, who can still learn new tricks!!! LOL!!! I have to laugh, seeing you working in shorts, and talking about 40 degree C heat. I'm in Central California, and freezing in 40 degree F cold!!! LOL!!! I never liked being cold, and when I was in the Air Force, I was always getting stationed in very cold places, Like Colorado, Idaho, and New Jersey. The older fellows never understood why I always volunteered for SEA duty ( South East Asia). I remember the Snake river in Idaho, freezing solid in the winter of 1972. It was minus 60 degrees F at night, and warmed to minus 40 degrees F, for a day time high. There was never that much snow, but it was blizzard conditions a lot of the time. When the wind stopped blowing, and the sun was out, you could get sun burned in below zero F. That beautiful blanket of snow reflected the sun at all kinds of different angles, and radiantly cooked what ever flesh was exposed. I enjoy your presentations, thanks again for all your efforts, they are appreciated!!! Tim
I think thing that is missing from this conversation is whether the cutting tool is hand ground HSS or whether a full form threading insert is used. Clearly as rake is included on both sides of a FF insert it is intended to cut on the back edge as well as the front, while a hand ground one, being a form tool, needs some assistance from a top slide on the larger pitch threads. Or am I missing the point?😉
@@chrisstephens6673 You missed that it was long known that plunging directly into the thread produced a poor thread and overloaded machines. Some now unknown machinist thought "always cut toward the spindle bearing". I
@@jayreiter268 that is where you have been misinformed, many yesrs ago I tested that very myth. I cut samples going straight in and flank feeding using the same single pitch full form insert on some 303 stainless and even under a microscope you could not tell which was which. There will be occasions when flank feeding is an advantage, flimsy machines or extraordinarily coarse threads but the myth you have to do it all the time is busted. I have not done the same test with a hand ground form tool but even then it is classically taught to take a spring cut plunging to remove any steps in the flanks. I subject is becoming more and more irrelevant these days as people in the know are removing their top slides altogether in the pursuit of increased rigidity and can then only do plunge threading.
I use this approach for threads of more than 2 mm pitch, but I work out a desired chip load/DOC, so I usually do less than the expected 50% move on the compound. The argument in favour of doing this rather than a straight-in cut is that my 40 year old Colchester 1800 has a bit of carriage backlash, so biasing the cut to ensure the leadscrew is under compression in the direction of travel is a good way to prevent chatter. To complicate things, I usually cut threads in reverse away from the chuck, with the tool behind the workpiece, so the cross-slide is moved towards me and the compound is moved away from the chuck. I often do plain finishing cuts away from the chuck as there's less wear on the back face of the leadscrew and gears and I get a slightly better surface finish. Or I might be imagining things! Great stuff Max.
Thanks . I have only used a rear tool post for parting . I think i would wind something the wrong way for sure with a rear post & opposite threading !!! 👍
The machinists at the steel mill would normally do a carbide insert tool straight in for the whole thread and were usually successful and quick about it. I try both methods here and there, but typically I am random on the cross slide, just to clean up the right flank a little. Not as precise, but it is a hobby shop for me. Enjoyed the vid, cheers Max!
I was taught this method of screw cutting as standard at TAFE back in the 1980’s. Using the compound slide at 30 deg was never even mentioned. I notice that popular machinist like Kurtis from Cutting Edge Machining also do it this way as standard. Personally these days, I usually offset the compound. Makes a lot more sense.
I was there in the early 80's as well ! Can not remember what methods they taught as i was screw cutting on lathes a couple of years before my apprenticeship . 👍
Hi Max, I wish I'd watched this before my last project. I got away with straight in cutting 5tpi but there were indeed some 'dramas'. I perhaps listened to people who said "I only ever go straight in" but recent events have taught me that's not necessarily good advice. My default is now to go in with the top slide angled. Cheers Paul
I used this method on a big Mazak with a good spindle brake. At the end of each cut, hit the foot brake and retract the tool simultaneously, into reverse, new cut and repeat. A couple of mimutes later at 350 rpm and five cuts all done. Material H13 tool steel hardened to 52 Rockwell C. The thread finish looked ground, just beautiful like it was cut on a CNC. Cheers.
@swanvalleymachineshop The biggest diameter in the Mazak was 510 mm x 450 mm long, being one half of a plastic injection mould for the eleven litre icecrean parlour tubs. We produced injection moulds for thin wall food containers and plant pots large and small. At the time circa 1980s, the lathe had Sanyo electronic read-outs. Also, as an attachment, a Minic hydrolic profile tool tracer. The lathe had power and accuracy. I pushed that electrical amp gauge to the max when shifting metal. Thanks for bringing back some great memories. Cheers
I have use this method since I learn up a single-point-thread-cutting and I still use it. To deal with compaund adjusting to 29 (29,5) deg and back to 0 zero is quite a struggle. Through practicle I noticed that up to 2...2,5mm thread pitch no need set compaund in 29 deg. Nowdays carbide tooling goes easy. Good luck!
This is the only method I've used, I came up with this as an apprentice when I thought how stupid the angled compound was. This method means you keep track of the depth cut and is also good if you have to meet a fixed stop point with very little runout.
Really like your videos, becoming one of my favorite channels to watch! I'm from the states and I too keep compound at 29 degrees all the time. However, I think I'll try setting mine up like your just to see how it works out.
This is the way I always cut a thread because of two advantages. Firstly sometimes the thread is a little tight because although you are to depth the tool isn't quite at the right angle. If this is the case you can give the top slide a little nudge and it often sorts out the problem. Second, when turning stupidly coarse threads you can cut to half depth and then cut to width with the top slide and then return to the start and cut to full depth. using that system I once cut a 4 tpi thread on a 3 1/2 Drummond driven by a treadle. I was a lot fitter back then!
Good tutorial Max. I remember David Wilks using that same set up, but with a different technique, to cut multi-start threads. I usually thread with the compound at 90 but just plunge in. For most pitches my lathe is rigid enough that I can do that. I'll keep your method in mind if I cut some large threads and have problems with vibration. We have a windchill of -40 C right now. No shorts for me. Ken
Cheers Ken . Yes , the compound is the easiest way for multi starts . Esp , like Dave was doing 5 starts ! Don't worry , the shorts only come out when the temp hits 40 ! 👍
I have used that method on internal threads. The only issue I have is keeping track of the feed depth between retracts. Using both the absolute and incremental on the dro helps though. We're you using a full form insert?
Full form insert , but for a larger pitch . Switch the DRO off Preso & just use the compound dial . Mark the dial with chalk , that's what i was taught ! 👍
This works great because it's doing basically exactly what you're doing when setting your compound to 29.5. The sine of 29.5 is ~.49, which is close enough to .50. Great vid as always!
Since the top slide is operating at 90 degrees to the cross slide, the angle that Max is achieving is actually arctan(0.5) = 26.6 degrees. To approximate 29.5 degrees the ratio of top slide to cross slide movement should be tan(29.5) = 0.566.
Another great example of Trigonometry in machining. Moving the compound half the distance of the infeed is in reality creating the same thing as a 30 degree angle cut with just the compound...BRILLIANT!
Hey it's 40 to 41 here also. Darn I forgot the minus sign. Great information Max. I could mail you a bottle of cold air. You could enjoy it and send it back with hot air. Would that cure the problem?😂
Yes , no worries there . But keep it to a minimum as the trailing edge will have a negative rake angle . Main thing is to have a enough side clearance to allow for thread lead angle . 👍
Great video Max! I have really been enjoying your content, as I only found your channel recently. Angled infeed is more common on conversational or CNC equipment with full form threading inserts in my experience. It's great to see you emulate that on the manual lathe! G'day from Alberta, Canada - the land of API pipe threads and frozen faces. Cheers 🍻
I feed straight in anyway with no issues. My 1943 Machinist hand book says that's A-Ok on 4-tpi or smaller. It does mention,(and I'm the first person on the interweb, pointing this out). Setting the compound and feeding in with it, does load 1/2 the cutter, but that's to take up the gear train slack. Plus I know it's hot down there. And I wear shorts year round. MI have a body shop that stays at 80 deg. f or 60 deg. C? year round. However those short shorts are gayer than gay. I you look ou Gay short pants in webster, that picture will show up. js I'll look around your channel and may subscribe.
Look ma i learn something new.........it all makes sense now with the tool pressure......and no its not all American way of leaving the compound turned, im still a newbie, but through the 3 lathes i have already owned i seen quite quickly how much rigidity i would loose on my smaller lathes with it kept at 29.5 degrees, so i keep my cross turned like yours all the time except threading, but now i know another way and im dying to try it , thanks max😊😊 i sure wish i lived next door to you , id be like the bad neighbor wanting to borrow a cuo of sugar except id be asking " hey max you wouldnt happen to have a foot or two of uuuummmm 4140 i couod borrow"........lol
Valid technique but flawed inspection process. Using a nut as a "gauge" is throwing away the standards that allowed us to build the modern world. Most machinists do it that way, including my former self, but it is actually unacceptable. Making a nice fit on that unknown and crappy looking nut will likely leave your shaft anywhere up to .016" oversize. It looks like your nut moves about .010 axially as you test the fit and that gives a pitch diameter clearance of ~.0087 but the nut can be .014 bigger than the min nut PD allowed while the shaft must be .0022 smaller than the nut min size for class 1a and 2a. There is only ONE correct way to size a thread and that is to measure it and make it to the dimensions set out by the standard. Then it is guaranteed to fit any properly made nut regardless of class.
The video was never about machining the thread to any specific tolerance , but about the alternative threading process . If i wanted to cut the thread to PD i would have done so , but that was not the point of the video . 👍
Good easy approach since the Tangent of 30 degrees is 0.577, darn close to 2:1. Where 29.5 degrees is 0.566. the compound angle to get 2:1 is 26.55 degrees.
If you have a DRO on your lathe, you'll be loathe to have the compound set at 29 degrees because any movement there screws up the DRO setting. When you make your living doing this, you tend to do what is most efficient, and a 90 degree setting is most efficient. Plus carbide inserts don't like a scraping cut on the back side, this will chip the edge that you're not even using! Laydown thread inserts are wonderful tech. They easily form two chip curls without a problem of interference. If you can keep the speed up, the finish is excellent.
I guess you watch Josh Topper as well then! An extra benefit of having the compound parallel to the axis would be to make it easier to pick up the thread again if the toolpost slips or you have to mess with the tool before the thread is finished.
Thanks Max , just about to make a boring bar for my shaper , 2” unf thread so may well try your method . Hey all the best from top of the South Island New Zealand 👍
You could use the tangent of 29.5 degrees as your relation of the feeds and be right on the money. Keep in mind some crosslides are graduated 1 to 1 and some to 1 to 2.
Leading edge is all about thread cutting. Big hydraulics require threads capable of withstanding assault that can reach forces . Maxy whips one out with scant regard for material discomfort . Machines are mentioned to be time savers. Not heart brakers.
Never did understand why the yanks prefer the offset compound infeed. Having the compound permanently offset means you can't use it to accurately set a shoulder length and then have to introduce a dial indicator in it's place. Direct infeed method is also much easier when chasing a damage thread.
Lol ! I work in both as i have imperial & metric machines . What most do not understand once a fraction is broken down to a decimal , the workings become the same as Metric . 👍
Yes , just not shown on YT . CEE would be the only other channel i have seen it . A lot possibly depends if you learnt from a European or an American background . 👍
G'day Max, looking very dapper there in ya shorties mate 👌 Thanks for this video mate, I was actually thinking about this the other day, watching screw cutting videos, the majority dont use the compound nowadays, I figured it had become outdated somehow? Thanks for sharing 👍
Not out dated Mate , just ones just a different method that can save a lot of time . Esp if you do not want to upset the location of your tool post . The shorts only come out when the temp hits 40 ! 👍
Yep great to see another learning opportunity Max. And sporting your lucky legs no less! 😜😂😂 Can’t say as I blame you it’s been beyond hot these last couple days, & a great time for the air con to go on the fritz. 😳😳😢 Keep up the good work mate.
Thanks for your great knowledge, as for the weather, it's snowing and it's 31°F and no power, and we're still forecasted 6°F lows 🥶🥶🥶🥶🥶🥶 which isn't normal for where we are in USA but we're really looking forward to summer here lmfao 😂
Wow , that sucks with no power . We get a lot of small power cuts here with the hot weather , everyone has their air con on ! 42 deg C , 107 F today ! 👍
Good video, I gave away swinging the topslide round in about the third year of my apprenticeship, the width at the bottom is easily obviated by always taking slightly less than half. Cut hundreds of threads like that quickly and easily in everything from aluminium through to Ledeburitic tool steel.
The first time I ever saw this method used was by another Aussie Machinist, i.e., Kurtis on his channel Cutting Edge Engineering. I'm a hobby machinist, who took a class in machining to get started, and was taught the traditional method with the 29 1/2 setting on the compound.
Thanks . If you are doing finer threads , just plunge straight in . Compound in line with bed . This way makes it easy to pick up the thread again if you have to remove a tool or one breaks . 👍
Hello Max and channel. Nice to see your summer as outside temp was -23C last evening here and forecast as to stay for most of the week. At my study, I'm watching from warm comfort and enjoying your kind lessons. I am working to improve my techniques and tool selection. Regards. McGary
Thanks for this explanation. I have watched Kurtis use this method. It took several videos for me to notice him bump the cross feed. he seams to do this by feel. He also threads without releasing the half nut as many do when left hand threading.
Nice demo,Max. I was taught both compound set at half angle and this method as an apprentice both in work and at technical college. The rule of thumb for ratio was roughly 30% to 50% of compound slide advance to cross slide infeed depending on the helix angle and thread depth,this requires a bit of experimentation but you soon get a feel for what is going to work for various thread forms. Also taught not to bother too much on shallow/fine thread forms as simply infeeding with the cross slide will produce a good thread,especially when using full form carbide inserts.
I used to use this method many years ago when I was a machinist. This was to avoid the tool cutting on all edges at once. Back then, we didn't know about the compound at 29 degrees method.
My milltronics cnc lathe offers 4 ways to have the lathe cut the threads. one was the way you just mentioned. i didn't know why one would need to do this till you mentioned the heavier threads. now it makes perfect sense. thank you
Thanks . Yes the CNC's have some interesting tool paths when it comes to threading . Never used one , It was NC & typing computer cards when i was at tech school & peg board control lathes at work , but we were not allowed any where near them as apprentices ! Back in 1982 . 👍
Vary helpful, I like the shot of the part being cut and as well being able to see you working the magic on the hand wheels, thanks for showing everyone who has an internet connection the right way to make chips.
Great tip I do it like that all the time but only a very small compound move never realised could move it half the in feed till your really close to size thanks max
1/2 is about the limit otherwise things turn ugly . Still have to leave a small amount for a couple of light finish cuts , straight plunge in . But you do that anyway with the angled compound method as well . 👍
A good-to-know technique that I have never heard of. Thanks Max.
Thanks 👍
Thanks for the show Max 🍻
No worries 👍
Not criticising your technique as I've wrestled with setting the 29-29.5 degree compound angle and my compound has heaps of backlash, so this technique is a gift.
Not trying to be picky, given that you're using 20 thou DOC on each pass, if you go to 11 thou on the compound to every 20 thou on the cross slide you'd be hitting 28.8 degrees.
Great video and HUGE thank you
Subscribed.
No worries , Cheers 👍
Absolutely lovely threads. And cut like a true Jedi Lathe master Machinist ! ☝️👍🏻
Thanks 👍
I suffered under the tutelage of an old German machinist, and at the same time I was taking machine shop in high school.
Klaus, always used the method you just presented, so I dared not do anything else in his shop. My High school teacher always had us set the compound at 29 1/2 degrees.
Neither man ever explained just why that threading was done the way it was.
Both methods worked just fine for me, and I was never questioned by any one in the companies I worked for. ( I think I was the only kid who was trusted to cut threads on valuable work pieces)
At University, the machine shop teacher noticed me using your described method, and muttered something about a " Bad European influence" that I never understood. But again, I always got to thread the more important projects we built for the school.
It was only a few years ago, after watching lots of different people cutting threads, on RUclips, that I did notice the difference in compound settings, And sure enough European, and Common Wealth machinist used your compound set at 90 degrees.
Previously I had only cut multi lead threads, by using the compound set as you have shown. I liked that method, as I could always fudge a bit and always got a perfect fit, something that was not always easy to obtain.
I used to think I was a pretty great machinist, but after watching some of the folks on RUclips, I look like a rank armature, even after almost 60 years of working in machine shops, including mine!!!
So, I'm an old dog, who can still learn new tricks!!! LOL!!!
I have to laugh, seeing you working in shorts, and talking about 40 degree C heat.
I'm in Central California, and freezing in 40 degree F cold!!! LOL!!!
I never liked being cold, and when I was in the Air Force, I was always getting stationed in very cold places, Like Colorado, Idaho, and New Jersey.
The older fellows never understood why I always volunteered for SEA duty ( South East Asia).
I remember the Snake river in Idaho, freezing solid in the winter of 1972.
It was minus 60 degrees F at night, and warmed to minus 40 degrees F, for a day time high.
There was never that much snow, but it was blizzard conditions a lot of the time. When the wind stopped blowing, and the sun was out, you could get sun burned in below zero F. That beautiful blanket of snow reflected the sun at all kinds of different angles, and radiantly cooked what ever flesh was exposed.
I enjoy your presentations, thanks again for all your efforts, they are appreciated!!!
Tim
Thanks . Sounds like you were taught the best of both worlds . 👍
Both of these methods are doing exactly the same thing, moving the cutting tool "forward", roughly 1/2 of the distance moved into the work.
I think thing that is missing from this conversation is whether the cutting tool is hand ground HSS or whether a full form threading insert is used. Clearly as rake is included on both sides of a FF insert it is intended to cut on the back edge as well as the front, while a hand ground one, being a form tool, needs some assistance from a top slide on the larger pitch threads. Or am I missing the point?😉
@@chrisstephens6673 You missed that it was long known that plunging directly into the thread produced a poor thread and overloaded machines. Some now unknown machinist thought "always cut toward the spindle bearing". I
@@jayreiter268 that is where you have been misinformed, many yesrs ago I tested that very myth. I cut samples going straight in and flank feeding using the same single pitch full form insert on some 303 stainless and even under a microscope you could not tell which was which.
There will be occasions when flank feeding is an advantage, flimsy machines or extraordinarily coarse threads but the myth you have to do it all the time is busted.
I have not done the same test with a hand ground form tool but even then it is classically taught to take a spring cut plunging to remove any steps in the flanks.
I subject is becoming more and more irrelevant these days as people in the know are removing their top slides altogether in the pursuit of increased rigidity and can then only do plunge threading.
I use this approach for threads of more than 2 mm pitch, but I work out a desired chip load/DOC, so I usually do less than the expected 50% move on the compound. The argument in favour of doing this rather than a straight-in cut is that my 40 year old Colchester 1800 has a bit of carriage backlash, so biasing the cut to ensure the leadscrew is under compression in the direction of travel is a good way to prevent chatter. To complicate things, I usually cut threads in reverse away from the chuck, with the tool behind the workpiece, so the cross-slide is moved towards me and the compound is moved away from the chuck. I often do plain finishing cuts away from the chuck as there's less wear on the back face of the leadscrew and gears and I get a slightly better surface finish. Or I might be imagining things! Great stuff Max.
Thanks . I have only used a rear tool post for parting . I think i would wind something the wrong way for sure with a rear post & opposite threading !!! 👍
@@swanvalleymachineshopIt would definitely require a rewiring of the brain. I’m at the age where that would be a monumental task. 😂
Another high caliber job good one Max
Thanks . Just another option . 👍
thanks Max, never seen this before, but will remember as needed
No worries Chuck . 👍
Thanks for the knowledge Max. It's always good to be aware of different ways to accomplish a desired result. Stay cool down under!😅
No worries . We have another week of 40's ! 👍
The machinists at the steel mill would normally do a carbide insert tool straight in for the whole thread and were usually successful and quick about it. I try both methods here and there, but typically I am random on the cross slide, just to clean up the right flank a little. Not as precise, but it is a hobby shop for me. Enjoyed the vid, cheers Max!
Thanks . 👍
Very interesting! Never thought of thread cutting this way. I will tuck it away for use someday.
No worries 👍
I was taught this method of screw cutting as standard at TAFE back in the 1980’s.
Using the compound slide at 30 deg was never even mentioned.
I notice that popular machinist like Kurtis from Cutting Edge Machining also do it this way as standard.
Personally these days, I usually offset the compound. Makes a lot more sense.
I was there in the early 80's as well ! Can not remember what methods they taught as i was screw cutting on lathes a couple of years before my apprenticeship . 👍
Hi Max, I wish I'd watched this before my last project. I got away with straight in cutting 5tpi but there were indeed some 'dramas'. I perhaps listened to people who said "I only ever go straight in" but recent events have taught me that's not necessarily good advice. My default is now to go in with the top slide angled. Cheers Paul
5tpi is way too much for a straight plunge , no wonder you had issues . Do you have it on video , i am a couple behind in your grinder series . 👍
Hi Max, I will send you an email about it. Cheers
Never saw that method before. Thank you for sharing - USA
No worries 👍
I used this method on a big Mazak with a good spindle brake. At the end of each cut, hit the foot brake and retract the tool simultaneously, into reverse, new cut and repeat. A couple of mimutes later at 350 rpm and five cuts all done. Material H13 tool steel hardened to 52 Rockwell C. The thread finish looked ground, just beautiful like it was cut on a CNC. Cheers.
Hey , no worries . I have a 21'' lathe that is a Mazak copy ! 👍
@swanvalleymachineshop The biggest diameter in the Mazak was 510 mm x 450 mm long, being one half of a plastic injection mould for the eleven litre icecrean parlour tubs. We produced injection moulds for thin wall food containers and plant pots large and small. At the time circa 1980s, the lathe had Sanyo electronic read-outs. Also, as an attachment, a Minic hydrolic profile tool tracer. The lathe had power and accuracy. I pushed that electrical amp gauge to the max when shifting metal. Thanks for bringing back some great memories. Cheers
@@AquaMarine1000 My one is a Chinese copy , JFMT 530 x 2000mm with rapids . The machine manuals are all Mazac copies .
Great video. I ŵas just commeting on @topper machining llc video on threading.you made it so much clearer
No worries 👍
I have use this method since I learn up a single-point-thread-cutting and I still use it. To deal with compaund adjusting to 29 (29,5) deg and back to 0 zero is quite a struggle. Through practicle I noticed that up to 2...2,5mm thread pitch no need set compaund in 29 deg. Nowdays carbide tooling goes easy.
Good luck!
Cheers . Yes , some lathes the compound graduations are not for counting back from 90 . 👍
This is the methode we see Kurtis from CEE use also. It works very well.
Same Rusty . Cheers . 👍
This is the only method I've used, I came up with this as an apprentice when I thought how stupid the angled compound was. This method means you keep track of the depth cut and is also good if you have to meet a fixed stop point with very little runout.
Thanks . Makes it easy to pick up the thread again if the tool should move or get damaged . 👍
Max, this sure would have helped Josh Topper last night on his job you watched yesterday......thanks for showing this technique, Paul
I am sure it would have . There are always methods we have forgotten or don't know ! Cheers 👍
Great tutorial. I like it. Will be using this method in the future.
Thanks 👍
That cut nice Max. Good to know. Thanks Tony
Cheers Tony . 👍
Really like your videos, becoming one of my favorite channels to watch! I'm from the states and I too keep compound at 29 degrees all the time. However, I think I'll try setting mine up like your just to see how it works out.
No worries , thanks . 👍
This is the way I always cut a thread because of two advantages. Firstly sometimes the thread is a little tight because although you are to depth the tool isn't quite at the right angle. If this is the case you can give the top slide a little nudge and it often sorts out the problem. Second, when turning stupidly coarse threads you can cut to half depth and then cut to width with the top slide and then return to the start and cut to full depth. using that system I once cut a 4 tpi thread on a 3 1/2 Drummond driven by a treadle. I was a lot fitter back then!
Thanks . Not sure if i would want to do it on a treadle lathe though ! 👍
An excellent machinist trick.
Thanks 👍
Good tutorial Max. I remember David Wilks using that same set up, but with a different technique, to cut multi-start threads. I usually thread with the compound at 90 but just plunge in. For most pitches my lathe is rigid enough that I can do that. I'll keep your method in mind if I cut some large threads and have problems with vibration. We have a windchill of -40 C right now. No shorts for me. Ken
Cheers Ken . Yes , the compound is the easiest way for multi starts . Esp , like Dave was doing 5 starts ! Don't worry , the shorts only come out when the temp hits 40 ! 👍
Nice work Max.
Happy New Year to ya.
Have a good day.
Thanks . Have a good one as well ! Cheers 👍
I have used that method on internal threads. The only issue I have is keeping track of the feed depth between retracts. Using both the absolute and incremental on the dro helps though. We're you using a full form insert?
Full form insert , but for a larger pitch . Switch the DRO off Preso & just use the compound dial . Mark the dial with chalk , that's what i was taught ! 👍
This works great because it's doing basically exactly what you're doing when setting your compound to 29.5. The sine of 29.5 is ~.49, which is close enough to .50. Great vid as always!
Since the top slide is operating at 90 degrees to the cross slide, the angle that Max is achieving is actually arctan(0.5) = 26.6 degrees. To approximate 29.5 degrees the ratio of top slide to cross slide movement should be tan(29.5) = 0.566.
It is an easy ratio to use . Just leave enough for a couple of straight plunge finishing cuts . 👍
I've noticed that Kurtis from CEE uses this method frequently and I often wondered what he was doing.
Now you know ! Cheers Greg 👍
Thank you Max!
No worries 👍
Another great example of Trigonometry in machining. Moving the compound half the distance of the infeed is in reality creating the same thing as a 30 degree angle cut with just the compound...BRILLIANT!
Thanks . My maths teacher used to continually hit me over the head with a 2'' thick text book ! 👍
Hey it's 40 to 41 here also. Darn I forgot the minus sign. Great information Max. I could mail you a bottle of cold air. You could enjoy it and send it back with hot air. Would that cure the problem?😂
Lol , our thermometer does not go down that low . 👍
and if one uses a hss tool one can grind it with a side positive rake, getting the nicest chips and cleanest cut possible.
Yes , no worries there . But keep it to a minimum as the trailing edge will have a negative rake angle . Main thing is to have a enough side clearance to allow for thread lead angle . 👍
Great video Max! I have really been enjoying your content, as I only found your channel recently.
Angled infeed is more common on conversational or CNC equipment with full form threading inserts in my experience. It's great to see you emulate that on the manual lathe!
G'day from Alberta, Canada - the land of API pipe threads and frozen faces.
Cheers 🍻
Thanks . I believe it's minus 40 over your way , we have a week of plus 40 !!! 👍
@@swanvalleymachineshop Yes sir, winter has finally arrived. -37°C this morning, feels like -45°C with the wind chill.
I feed straight in anyway with no issues. My 1943 Machinist hand book says that's A-Ok on 4-tpi or smaller. It does mention,(and I'm the first person on the interweb, pointing this out). Setting the compound and feeding in with it, does load 1/2 the cutter, but that's to take up the gear train slack. Plus I know it's hot down
there. And I wear shorts year round. MI have a body shop that stays at 80 deg. f or 60 deg. C? year round. However those short shorts are gayer than gay. I you look ou Gay short pants in webster, that picture will show up. js I'll look around your channel and may subscribe.
Lol ! No ass less chaps or leather caps here !!! 👍👍👍
Look ma i learn something new.........it all makes sense now with the tool pressure......and no its not all American way of leaving the compound turned, im still a newbie, but through the 3 lathes i have already owned i seen quite quickly how much rigidity i would loose on my smaller lathes with it kept at 29.5 degrees, so i keep my cross turned like yours all the time except threading, but now i know another way and im dying to try it , thanks max😊😊 i sure wish i lived next door to you , id be like the bad neighbor wanting to borrow a cuo of sugar except id be asking " hey max you wouldnt happen to have a foot or two of uuuummmm 4140 i couod borrow"........lol
Lol , cheers 👍
Supprised no-one on RUclips has shown this method, especially useful to hit numbers when you have dro on cross slide, but not on compound.
I only know of one other person , Curtis from CEE that does it on YT .
Thanks for the information I never I always wondered how screws were made in the threads the automatic feed... Alo to fuckin know forsure..
No worries 👍
Valid technique but flawed inspection process. Using a nut as a "gauge" is throwing away the standards that allowed us to build the modern world. Most machinists do it that way, including my former self, but it is actually unacceptable. Making a nice fit on that unknown and crappy looking nut will likely leave your shaft anywhere up to .016" oversize.
It looks like your nut moves about .010 axially as you test the fit and that gives a pitch diameter clearance of ~.0087 but the nut can be .014 bigger than the min nut PD allowed while the shaft must be .0022 smaller than the nut min size for class 1a and 2a.
There is only ONE correct way to size a thread and that is to measure it and make it to the dimensions set out by the standard. Then it is guaranteed to fit any properly made nut regardless of class.
The video was never about machining the thread to any specific tolerance , but about the alternative threading process . If i wanted to cut the thread to PD i would have done so , but that was not the point of the video . 👍
Good easy approach since the Tangent of 30 degrees is 0.577, darn close to 2:1. Where 29.5 degrees is 0.566. the compound angle to get 2:1 is 26.55 degrees.
Thanks 👍
If you have a DRO on your lathe, you'll be loathe to have the compound set at 29 degrees because any movement there screws up the DRO setting. When you make your living doing this, you tend to do what is most efficient, and a 90 degree setting is most efficient.
Plus carbide inserts don't like a scraping cut on the back side, this will chip the edge that you're not even using!
Laydown thread inserts are wonderful tech. They easily form two chip curls without a problem of interference. If you can keep the speed up, the finish is excellent.
Cheers 👍
That method is how I cut all threads.
Cheers , it has been around for along time . 👍
Many thanks again Max. Always informative, always interesting. Keep it up.
Thanks 👍
I guess you watch Josh Topper as well then! An extra benefit of having the compound parallel to the axis would be to make it easier to pick up the thread again if the toolpost slips or you have to mess with the tool before the thread is finished.
Exactly that . Also easy to chase damaged threads . 👍
Thanks Max , just about to make a boring bar for my shaper , 2” unf thread so may well try your method .
Hey all the best from top of the South Island New Zealand 👍
Thanks , must be a tad cold down that way ! I am from Wellington . 👍
That’s the equivalent of setting the cross slide at 30 degrees.
sin(30) = 0.5, which is exactly what you did .
Very close too . 👍
I like it! Cuts very nicely and easy to operate. Great job! Now, go buy some pants. Those toothpicks you're standing on could get injured in the shop.
Thanks . Lol , the toothpicks only come out when the temp gets to 40 deg C ! 👍
You could use the tangent of 29.5 degrees as your relation of the feeds and be right on the money.
Keep in mind some crosslides are graduated 1 to 1 and some to 1 to 2.
Lol , my cross slide is graduated in direct for inch and diameter for metric ! 👍
Leading edge is all about thread cutting. Big hydraulics require threads capable of withstanding assault that can reach forces . Maxy whips one out with scant regard for material discomfort . Machines are mentioned to be time savers. Not heart brakers.
Thanks 👍
Never did understand why the yanks prefer the offset compound infeed. Having the compound permanently offset means you can't use it to accurately set a shoulder length and then have to introduce a dial indicator in it's place. Direct infeed method is also much easier when chasing a damage thread.
It's just the way they have always done it i guess ! We were taught the English methods . 👍
I was wondering with those summer shorts you have on, do Australian snakes jump?
Not sure , i jump first ! 👍
Thank you.
Cheers 👍
When I start hearing thou, I lose interest. imperial measurements, sound like estimates.
Lol ! I work in both as i have imperial & metric machines . What most do not understand once a fraction is broken down to a decimal , the workings become the same as Metric . 👍
The only time I cut threads using any other method than what you just demonstrated was at Tafe college.
No worries 👍
Thought this was common practice. I'm farther ahead then you think.
Yes , just not shown on YT . CEE would be the only other channel i have seen it . A lot possibly depends if you learnt from a European or an American background . 👍
Interesting technique, one I haven't seen before. Thanks for sharing, Max.
No worries Rob . Cheers 👍
Thanks Max, I’ll try this out soon. Cheers
No worries Matty 👍
G'day Max, looking very dapper there in ya shorties mate 👌
Thanks for this video mate, I was actually thinking about this the other day, watching screw cutting videos, the majority dont use the compound nowadays, I figured it had become outdated somehow?
Thanks for sharing 👍
Not out dated Mate , just ones just a different method that can save a lot of time . Esp if you do not want to upset the location of your tool post . The shorts only come out when the temp hits 40 ! 👍
To be fair you rock the shorts 😂
Very good information. Thanks for that!
No worries 👍
I have this niggly feeling that Max knows what he is talking about!.
Lol , Cheers 👍
👍 Looks good.
Thanks 👍
Can't sympathize. Its -24 C here!
A tad cool ! Cheers 👍
Nice job 👍
Thanks 👍
Brilliant camera work Max, I'm looking forward to getting back on the lathe!
ATB,
Cliff
Cheers Cliff . 👍
I am very impressed and learn from your work
Thanks 👍
So what grade of steel are you cutting?
E470 Euro Hollow Bar . 👍
I hear his Aussie accent and I click Like!
Thanks 👍
Is this method just using a straight depth calculation.
Yes . Direct reading on the cross slide , straight in . 👍
Nice legs...I mean nice threads !!
Lol !!! 👍👍👍
Yep great to see another learning opportunity Max.
And sporting your lucky legs no less! 😜😂😂
Can’t say as I blame you it’s been beyond hot these last couple days, & a great time for the air con to go on the fritz. 😳😳😢
Keep up the good work mate.
Cheers Ian . 👍
looking Spiffy in your summer gear Max, cheers from he other 'Sunshine State', Florida, Paul
Lol , thanks 👍👍👍
Thanks for your great knowledge, as for the weather, it's snowing and it's 31°F and no power, and we're still forecasted 6°F lows 🥶🥶🥶🥶🥶🥶 which isn't normal for where we are in USA but we're really looking forward to summer here lmfao 😂
Wow , that sucks with no power . We get a lot of small power cuts here with the hot weather , everyone has their air con on ! 42 deg C , 107 F today ! 👍
Another well made and informative video. Thanks Max.
No worries 👍
Good video, I gave away swinging the topslide round in about the third year of my apprenticeship, the width at the bottom is easily obviated by always taking slightly less than half. Cut hundreds of threads like that quickly and easily in everything from aluminium through to Ledeburitic tool steel.
Cheers 👍
Good information, I appreciate you sharing. Sorry it's warm where you are at. It's 4f with snow and - 13f wind chill.
Thanks 👍
The first time I ever saw this method used was by another Aussie Machinist, i.e., Kurtis on his channel Cutting Edge Engineering. I'm a hobby machinist, who took a class in machining to get started, and was taught the traditional method with the 29 1/2 setting on the compound.
Thanks . If you are doing finer threads , just plunge straight in . Compound in line with bed . This way makes it easy to pick up the thread again if you have to remove a tool or one breaks . 👍
Hello Max and channel. Nice to see your summer as outside temp was -23C last evening here and forecast as to stay for most of the week. At my study, I'm watching from warm comfort and enjoying your kind lessons. I am working to improve my techniques and tool selection. Regards. McGary
Thanks . We have a week of 40 C ! 👍
Nice one max send over some of that sun when your finished with it 😂
I have finished with it ! Cheers 🍺🍺🍺
Thanks for this explanation. I have watched Kurtis use this method. It took several videos for me to notice him bump the cross feed. he seams to do this by feel. He also threads without releasing the half nut as many do when left hand threading.
No worries . I think he does a lot of threading imperial on maybe a metric leadscrew , hence you have to stay engaged for the return trip . 👍
Max, I suppose that means your root will be rooted. Thanks for slipping that in indeed. Jeff.
Surprisingly easy to root your root ! 👍
Nice demo,Max. I was taught both compound set at half angle and this method as an apprentice both in work and at technical college.
The rule of thumb for ratio was roughly 30% to 50% of compound slide advance to cross slide infeed depending on the helix angle and thread depth,this requires a bit of experimentation but you soon get a feel for what is going to work for various thread forms.
Also taught not to bother too much on shallow/fine thread forms as simply infeeding with the cross slide will produce a good thread,especially when using full form carbide inserts.
Thanks . Over 8 tpi or under 3mm , i just plunge straight in . 👍
Good one Max, that's my preferred method as I'm generally too lazy to swivel the compound and, saves me having to set the tool square to the work! 🙂
Any which way ! Cheers 👍
Beauty.. thanks Max!
No worries 👍
Another great bit of info as you never know when an machining operation will give trouble. Thanks again Max Cheers
Thanks 👍
It is winter here we have been in sub zero weather - 20deg F all this next week about zero . I will have to try that threading method sometime
Thanks . About 5 deg C would be our coldest on average . 👍
Ive seen Curtis over at CEE and wondered what he was doing. This explains it cheers Max
No worries 👍
I used to use this method many years ago when I was a machinist. This was to avoid the tool cutting on all edges at once. Back then, we didn't know about the compound at 29 degrees method.
Cheers 👍
Good info. Hope Josh sees this!
Never know ! Pretty sure it would have made it easier for him . 👍
Hollow bar,AKA pipe.
Google Hollow bar ! 👍
My milltronics cnc lathe offers 4 ways to have the lathe cut the threads. one was the way you just mentioned. i didn't know why one would need to do this till you mentioned the heavier threads. now it makes perfect sense. thank you
Thanks . Yes the CNC's have some interesting tool paths when it comes to threading . Never used one , It was NC & typing computer cards when i was at tech school & peg board control lathes at work , but we were not allowed any where near them as apprentices ! Back in 1982 . 👍
Vary helpful, I like the shot of the part being cut and as well being able to see you working the magic on the hand wheels, thanks for showing everyone who has an internet connection the right way to make chips.
No worries 👍
enjoyable!!! cheers
Thanks 👍
Surprising to see someone in shorts when there is snow on the ground and below freezing here. Watch out for those hot chips. Thanks for the video.
Lol , they only come out when the temps hit 40 ! 👍
I just found your channel. I never thought about doing it that way.Great idea
Cheers 👍
Great tip I do it like that all the time but only a very small compound move never realised could move it half the in feed till your really close to size thanks max
1/2 is about the limit otherwise things turn ugly . Still have to leave a small amount for a couple of light finish cuts , straight plunge in . But you do that anyway with the angled compound method as well . 👍
Wow that was cool and a perfect result. . Amazing.
Thanks 👍
Glad I decided to stop by today, I learned a new threading trick, Thanks
Cheers . It's a good method but real easy to stuff up until you have done it a couple of times ! 👍
Good one. Something I didn’t know. Thank you Max. 👍🇳🇱
No worries 👍
I would have a time with your lathe I'm use to the half nut on the right side and backing out with my left hand
My big lathe is like that ! 👍