Josh, your machining the thread with the moving follow rest took me back 64 years when I was on my apprenticeship We had a pile of rods not too dissimilar to your job to thread, and I and two other 'appies' were set up on three lathes until the job was finished. Until you showed your video, I had never seen that particular operation shown again. Takes me back. I was an Electrical apprentice, but our works manager insisted that all apprentices, went through the machine shop, fitter's benches and welding areas during our five years, and that training stood me in good stead for the next five decades. Enjoy your videos; Happy New Year.
Back in the 70’s while serving my apprenticeship, I used to turn 3ft long buttress thread form lead screws using a single point tool and a travelling steady. I remember it so vividly!
50 years making chips a few points from lead screw cutting 1st. Cutting straight in with crossslide almost doubles your tool pressure compared to compared to compound 1/2 - 1 degree less thread angle 2nd. A collar on back of spindle with 4 set screws will control whip and stiffen shaft protruding beyond chuck 3rd. Shoes on follow rest that contact more surface (we made pucks that slip over original with radius .005"-.010" over shaft size for more surface contact) rather than line contact that could mar finish if to tight. Still great job overall keeping trade alive all the best
Suggestion on preventing the tool post from moving due to cutting forces, put a sheet (about 0.125" to 0.25" or so) of soft aluminum or copper between the tool post and T-slot on the compound. The soft metal between the tool post (hard) and compound (semi hard) will slightly deform increasing friction between the tool post to compound. Same idea as using soft metal pads with a 4 jaw or 3 jaw chuck to prevent slipping and damaging the work. Adding to small slots on the tool post T-nut side facing the top of the compound's T-slot will move the clamping force away from the edge of the compound's T-slot. This helps to prevent T-slot break out and loads the compound T-slpt towards the stronger walls instead of the T-slot edges. Nice job on threading such a long round bar.. long thread runs with single digit thread pitch on large OD's is never easy or simple.
Just out of interest the thread I had to machine was 3inch dia, 4TPI 2start Acme plus the bronze nut , first made thread plug gauge using wires to measure then made nut to suit gauge , because the male thread was about 5 foot long so no way to offer male up to the nut ,nut was about 6ins long , took long time to make these think I had 4 sets to make was lifting screw for very large variable voltage trans former
Idea/suggestion to aid with the chatter when threading this long round bar, consider making a sleeve (bearing bronze or 12L14 steel or similar) with about 0.002"/0.003" clearance to the OD of the round bar about 2x the OD which in this example would be about 4" long with some means of attachment to the follow rest instead of the follow rest fingers. Adjust the sleeve to just clear the threading tool. This sleeve will help to reduce the "plucked string" effect of threading a long round bar. The threading tool is essentially the finger pluck on a guitar string, the length of the round bar is essentially the string being plucked. The entire round bar goes into resonance compete with waves.. some means to reduce the energy put into the round bar can and will reduce this effect. What the traveling follow rest bushing does is to reduce the "string plucking" effect by absorbing the energy that would have gone into the long round bar causing chatter during the thread cutting operation. Lubrication of the traveling steady rest bushing is essential. While the follow rest fingers do help prevent the Rond bar from climbing over the threading tool, the follow rest fingers does not suppress or reduce the energy transmitted into the round bar during the thread cutting operation, the traveling bushing does a better job of reducing the energy transmitted into the round bar and supports the round bar much better than just follow rest fingers when properly set up.
@1:49 Like the old saying goes, ask 10 machinists how to do something and you'll get 11 different answers. Moral is you can take many routes to get to the same destination. Great video as always Josh! 👍👍
It's just my opinion, but you are fighting torsional springback. Kind of like using a 24" socket extension with an impact gun. There is a more angular displacement in the bar the farther you are cutting away from the chuck. Also, because you have a fairly new lathe; I would check the preload on the headstock bearings. I fought chatter with my lathe and found it to be too loose. After adjusting the spindle bearing nuts, no more chatter. Just a suggestion. Oh well, if it was easy, anyone could do it! That's why you got the job. Good luck buddy!
The 30° feed in angle can be done with the compound set parallel to the spindle as it is here in the video. Feed the compound exactly 1/2 of the amount the cross slide is moved in for each cut which produces the 30° of tool movement. The advantage, of course, is half of the cutting pressure versus cross-slide feed in only.
Actually would need to feed the compound slightly more to get a true 30° angle but the 1/2 amount keeps a slight amount of cutting pressure on the right hand thread flank for stability.
I usally use your method and it works fine ,as for the tool post i made a block and put it behind the the tool post and put acouple dowels and two socket head cap srews keeps it from turning on you.
Hi Josh, that chatter had me going a couple pf times! Good job, handeld as the craftsman you are, I allways admire your knowledge and expertise mate. Thanks for posting, I really enjoyed watching this one, have a fine 2024.
I learned a long time ago to just plow these threads in, then fine time the chatter out. But this one had me a little worried. Luckily it came out well.
Regarding the steady, seems to me if it works, it works. I'm just a hobby guy who hopes to make a few bucks with my machines in 5-10 years once I retire, so I appreciate your output.
I do long thin walled gun barrels with a hydraulic steady rest. One thing I’ve found highly beneficial is to get your cutting tool as close to the traveling steady as is reasonable. Thanks for the video.
great job i will make a suggestion when you are cutting corse threads with the cross slide set your compound parallel to the threads and if you go in 100 on the cross slide then move the compound forward half the amount of the in feed 50 that way you will be doing most of the cutting on the leading edge of the insert. just a suggestion
G'day Josh. Lots of good feed back here. My take on it is 1 check live center in good condition and make your center in the bar deeper. 2 support the bar hanging out the back of the lathe, its like a tuning fork whipping around. 3 and my old stand by a piece of wood with a vee cut in the end and jam it the steady, works most time. Like what you do,
That sounded like cutting on a piece of ETD150. Can't offer anything else that wasn't already mentioned. One thing I do when cutting long winded threads like this is to back off your live center to where it is just touching and able to turn it by hand. Thanks for sharing, Ken
Thanks Josh, I really enjoyed this one. I appreciate you taking the time to show us how to do it right the first time, Looking forward already for your next one.
Huh, seems like a bit of a design oversight on the Lion lathe that you can't get the follow attached when the compound is set to 29.5? Maybe it's just me, but threading long thin threads is one of the most common reasons why I find myself needing to use a follow. So doubly odd that it won't fit when the machine is configured for doing that exact thing. Awesome vid, as always. Thanks Josh!
Josh, I know you had some minor struggles with this one, but your attitude and skill make it look easy. I had to laugh when you made the comment about the compound angle. I'm not a machinist, but I make or repair my own parts on machines and know why the angle is set the way it is for threading.
That third point basically does nothing in this case BUT would be damn handy if threading tool upside down in reverse and away from the chuck if you ever wanted to.
Hey there, top, you might already know this, but I thought I might bring it up sometimes a piece of brass about 2 inches in diameter, 5 inches long or a piece of lead about the same size or a hammer handle placed in the right spot can really deal with that vibration, it ain’t a for sure, but sometimes it really works, sometimes I find less vibration if I feed towards the tailstock, my old boss used to feed towards the tailstock all the time and that’s where I picked it up, you know just turn your tool upside down and go the other way anyway looks like you’re having fun🤠
The lathe in the shop at my last job had a storage stand for the steady rest that was behind the headstock. The steady rest lined up with the headstock bore and could be used on long shafts to keep the stock from whipping around.
@@TopperMachineLLC It really works pretty well. The one I worked with was heavy, which made it difficult to move but it was stable. I was going to put retractable wheels on it, but I never got a round tuit.
@@ellieprice363 The one I worked with had a serious case of gravity. It pretty much stayed put. I would have put it on rails to keep it in line with the headstock bore, but it just wasn't necessary. Plus, rails in or on the floor are a safety hazard..
25 years, I've found short cuts and tricks to do the job. Some learned from others, some on my own. The end result is still a good product and happy customer.
Another outstanding job. I have never seen a thread that long single pointed before. Was nice watching the process. 👍👍 You certainly get into some heavy duty jobs. Have a great weekend.
Machinist hands. I winced when you put your hand on the threads with the rod turning. Then I remembered High School machine shop instructor that would handle bare handed hot pieces coming out of the lathe or mill. he thought it was funny to hand them to the students.
Takes me back to tie bars turning for injection molding machines. Some presses were 1200 ton, oh my. The nasty chip coils are scary for sure. Nice work, thank you. Cheers
FYI we had a milling head for the lathe and thread hob vs single point. As I recall some 50+ years later 😊 it made a pretty decent finish. Not a suggestion more of 😊a question. What do you think?
been machining for awhile now and never seen your method on the steady rest, I will have to try it, might not work on pipe though and that is what i do a lot of, I'm afraid it isn't round enough without putting a truing band on it to start with.
I did not know that you can do multiple passes to make threads. I am not a machinist, so watching your channel is always interesting and informative. That crane sure is handy. You have made some nice improvements in your shop. If I only knew what you have forgotten ........I would be smart. You done a nice job filming. How nice to see Rocky for second. It is always good to see you.
I’m gonna be honest with you guys , listening to the chatter was like chalk board 😅 . I just wanted to put my hands all over that machine to find out where that chatter was coming from.😂. Maybe applying a little pressure somewhere could’ve stopped it ? Very nice work. The nut did not have no wiggle wiggle perfect.
@@TopperMachineLLC Josh, as dumb as it seems, I was wondering if your tail stock live center had gotten slightly loose..... I have been turning 1 inch sch 40 6061 pipe and 1 1/4 inch trying to get chatter for decorative effect.....when you want it, it is very hard to achieve......cheers, Paul
I really enjoyed seeing good single-point threading, especially the nice, meaty ones like these. Thanks for another fascinating video. In your spare time (hohohoho) you might consider making a floor steady stand for supporting bar stock that hangs out behind the headstock. Keith Fenner used to do lots of prop shafts and had a hole in the wall for the shaft to pass through and then a floor steady with rollers in the adjacent room. Alternatively, a simple stand to which you mount your lathe's steady rest can be used the same way. Of course, if this isn't a common problem for you it probably isn't worth the effort.
I'm guessing, the lack of chatter at the end could be proximity to the head stock but also because of the additional pressure being put on the uncut rod after the adjustments for the threaded portion. I also wonder if putting a roller stand to lightly contact the rod sticking out of the back of the head might reduce the vibration a touch. I am no machinist but I do work on my own stuff with a small lathe and mill. I guess I need to research the compound angle thing in case I ever do try to cut threads.
No problem you can do the same by setting compound 1deg. less parallel but you move compound 1/2 of indeed each cut but I found it to easy to miss 1 adjustment or the other moving both each cut. Good content overall from old retire tool and die maker
That is the following rest that "sing" a song of the threats over it was rubbing. I wish a Happy New Year to you and your family.Greetings from Germany.
Hi Good to see video like this , I had to do something similar in my machinist days and chatter was always problem,I would keep the top/compound slide parallel to bed ,had the tool post dowelled to top slide to prevent it moving ,with very coarse pitch cutting full form is large chip load , as the thread got deeper I would move top slide forward/back so only cutting on one side of tool at time keep going deeperback and forth til full thread depth was reached , our customer would not except any chatter on threads
Oh Yes 1018 not great material at anytime another thing I just remembered was I made longer pads for the travelling steady so they would support over greater length@@TopperMachineLLC
@@TopperMachineLLC 1018, I have lots of problems getting a decent finish on that stuff.....gimme something a little harder.....to bad they did not spec 12L14....12L14 is also stronger than 1018 and has a much higher tensile strength.
I would sometimes put a slight top rake on my threading insert when plunging straight in like you were. That way the full threading tool profile would NOT be making 100% contact each pass, because it was relieved slightly by the top rake of the threading insert. Try it next time... It couldn't hurt, especially if your hand fitting to a given nut
You seem to know better when it comes to the proper machining methods. An inexperienced machinist would run into many difficulties having watched you produce a part the way you are. I liked that you mentioned the 29-1/2 degree setting.
Nice to see some lathe work. Wondering if the bearing surface from the steady rest rollers is wide enough. As with such a pitch, it creates pretty wide voids. Also choosing the next lower speed would have been interesting to attempt so it could have perhaps alleviated somewhat the chatter. I would revise the tool post. The amount of torque you put on that wrench (nut) seems quite abnormal to me. Great job and great project to execute and a pleasure to watch from our stand point! Thanks for sharing Josh. God Bless.
Remember that you turned the toolpost and are now cutting on both sides of the tool at the same time. Turning the toolpost as far as it will go towards the follower gets it nearer to 29.5 degrees so it is cutting on the front edge of the tool mostly.
Holy crapola, you did not indicate in the steady rest or make a scratch pass to verify the thread pitch and are teaching new machinists bad habits. The threading God will punish you the next time you cut threads. :-) It is only the amateurs who find fault with what well experienced machinists do when they should be taking notes instead. Thanks for taking the time to video and edit the mega threading process.
I never do a scratch pass. In 25 years I only had one f-up and that was when I had COVID and quite sick and wasn't thinking. Needed 16tpi instead of 18. Lol.
40:00 I recently purchased (2) 1 7/8 8 tpi nuts , one from McMaster and one from Zoro....... these were to be used as protectors for the spindle thread on a South Bend Lathe..... well, the McMaster nut went on in both directions with no issue, but the Zoro nut would only go on in one direction and then bind..... Quality is not the same from vendor to vendor or manufacturer.... I have no idea which country they came from.....but hopefully your client will be buying quality nuts and not blame you when they do not fit.... Paul down in Florida
Have you thought about making some kind of support stand for long stock out back of the headstock? It'd have to be pretty substantial for the stuff you work on I suppose.
Great watching along with your commentary. Unusual to see working along way from the chuck as well. Is it to reduce the amoult the bar sticks out from the rear of the spindle?
Great video. You know, when you are getting toward the end, there is a lot of tool edge contact in the V when you are feeding straight in like that. Maybe with the compound at 29 1/2 you could feed straight in for awhile and then finish up feeding the compound in, reducing the tool contact to just the front side which might help with the chatter. Just sayin.....Dave
@@TopperMachineLLC I see you were banged up for room to angle the compound with the follower rest . Another way is to run the compound parallel with the bed & advance the compound a few thou for every infeed cut on the cross slide . This keeps the tool load mainly on the lead edge & reduces the load on the trailing edge . As long as the compound movements are only a few thou , it will not alter the thread profile & then just a couple of straight in feeds for the finishing cuts . Watch the lead angle on some of those threading tools as well . Cheers 👍
@@TopperMachineLLC I recently tried 15* (half of the 29.5* from dead on) at the suggestion of a machinist buddy on a tough material 1.375"-6tpi job and it worked awesome. Lightened the chip load considerably but still cut the proper form of the tool. I was surprised it worked so well.
I have the same issue with my lathe with clearance with the compound so I milled the follower a little so I have clearance now . Not much load on a follower anyway.
Far from an expert here, but on long shafts, I had good luck supporting the outbourd end in a v-groove cut in a 4×4 set on a stand. Holding a piece of heavy brass on the working end works on some things. Mike
Josh, Ive watched this over and over. dozens of times trying to figure the chatter out, and like you wouldnt have done anything different than what you did....your Lion lathe is way more than capable of what you are asking of it on this job.....the only remote thing i can think of would be that maybe that the live center you are using is worn and has a skosh of lateral flex in it. I might try one of Curtis at CEE's techniques in using a tailstock mounted 3 or 4 jaw rotating chuck, indicate it in, cut the thread that way and see what happens....worst would be it fixes the chatter and all you have to do is chop off the amount you were holding with the tailstock chuck.....just a thought.....so far this "terrible storm" they were forecasting has been nothing but a figment of their hype and imagination....Yaaaaaayyy for that!!! Don
josh maybe the vibration come from steady rest,i dont sure,i just observe the vibration gone when the steady rest near the chuck, and thanks for that awesome video,no one do that in youtube.thanks again.
Is it possible that your chatter was coming about as a result of you cutting on both faces of your cutting tool at the same time, versus having the compound set at 29.5 and cutting on just the leading edge of the cutting tool and doing all your advances with the compound.....??
You could try changing the speed of the cut. Doing so changes the chatter frequency and will at least lessen the chatter. I've gone back and forth between selected speeds to try to eliminate it. Keep it from talking back. Nice work, nice shop.
Follow rest. Are the inserts removable. Can you use belville springs under them to maintain the tension. Overhang. Drop in concrete anchors sunk slightly deeper so flat head allens keep the floor level and dirt out of the threads allowing a simple angle iron support to be bolted to the floor. The bottom tube is square and has a stud up thru the middle for a tube that turns out with jacking feet on an offset so this device is only a few inches thick for easy storage. This could have 3 rollers not just to support the overhang but to dampin any chatter that goes to the overhang and back to the tool path. I totally agree with others on checking the spindle break away rotational torque to set the preload on the bearings. Like a rear end pinion bearing 10 to just under 15 inch pounds of rotational breakaway torque for preload. I can't imagine what damage is being done to the bearing surfaces with all that chatter. Is there a neutral position where no gears are engaged to the spindle so you could use an automotive stethoscope to listen to the spindle bearings. For a quick test. Slide a piece of bar so its balenced in the chuck. Indicator on the top cover measuring the top of the chuck. How much does it deflect when you push up and down on the bar stock. Lastly. Imagine a knurling head that has thread shaped wheels to put the ulitmate rolled finish on threads.
Josh, I was wondering if maybe having your tool closer to the center of the follow rest, that the chatter may be reduced.....looking at your QCTP on the compound , it looks like it could be moved left to get the tool closer to center on the follow rest ???? Just a comment from an occasional machinist lathe guy, I ha by no means the experience you or many of your others viewers have.....cheers, Paul
hey Josh i was wondering if it would be any use to set up another following steady on the other side of the tool post or even on the right hand side of the saddle? seems to me the vibration comes in when there is a fair bit of cantilever from the supporting ends. Not critiquing in any way i think you've done a fantastic job there.
Plunge cutting threads does tear/rip up the edges wearing the follow rest plugs. You could try turning the topslide back around to 90 degrees and after some plunge cuts try the side cut method to remove chatter marks? Whilst experimenting with rev changes. Thats if theres ample room between tailstock live centre, maybe a longreach live centre would help. All the best with your business, you are very good at what you do, cheers. Ps. Ive only recently retired from payed work but still keep active in my home shop with small steam train hobby.
Since this is only the second time I've used a follow rest in 25 years, I still have a lot to learn. Just keep at it until I find what works best or get good advice.
@@TopperMachineLLC Josh, I think you mentioned in the beginning that the follow rest had hardened jaws.... but I Amy be mistaken, but if they are, they would surely not be chewed up as others have mentioned, did you mention the alloy of the bar stock? thanks, Paul
Very Nice, not a fan of coming down the half angle as it means using 2 dials it is a US thing as the tool shops I have worked in the UK also watching Australian videos they just get it done right the first time!!
Josh I think the chatter may have been because you had the compound set at 0 degrees instead of 29.5 degrees. You had no choice in the matter obviously but I was watching someone else doing some single point threading the other day on YT and they said that when they cut with a straight compound they'd advance the compound by 10% of the feed in rate. This compensated for the missing 29.5 degrees on the compound. They said that they had always used this method when straight cutting a thread and it worked out well for them. It reduces the tool pressure enormously (according to them) because a straight in cut when threading produces pressure on all sides of the cutter the deeper you go, whereas the 29.5 degree compound ensures the tool only cuts on the forward edge, they explained. Seemed very logical to me. Might be worth a try. Cheers.
What I used to do for long threading, I move tool little forward for each pass further in. So the leading edge of the tool do major cutting. It avoid the cutting vibration. The chatter comes from back side edge of cutting tool.
Going in at 29 degrees would greatly reduce the tool load and probably reduce the vibration. Also, there seems to be a resonance problem. With cylinders, I have packed the inside with clay to solve the problem and on bar I've had to adjust the length beyond the chuck, adjust speed and even located a weight along the bar. If the compound creeps, tighten the gibe.
Really like it, maybe a future shop project would be making a rearward steady when youve got the time? Saves a bit of time throwing the steady on because it can just live there.
So I totally understand the reason for setting the compound to 29.5 degrees. However - you ended up going straight in anyway without any problem. I have single pointed threads at both 2.9.5 and just straight in and frankly couldn't see a difference. Going to try again today - maybe my old lathe was so lightweight it just sucked whichever way. So do you generally see any kind of a difference? Do you think having to go straight in had anything to do with the little bit of chatter? I can't see why it would - seems like that is just a matter of support of the bar at the tool position.
P.S. I'm not a machinist and don't claim to be. If you're not making a living (or trying to) machining parts, then I don't think the term machinist really applies. I'm OK calling myself an amateur or a hobbyist. The machinists at work don't laugh at me too much. 🙂
Since I had to go strait in, I was putting cutting pressure on both sides of the insert. It is always best to go in at 29.5, as you are only cutting on one side. I think most of that chatter was from cutting both sides of the thread instead of the leading edge. I had double the tool pressure trying to lift the bar. The other issue was the material, but I couldn't convince the customer to go to something better. The old "This is what we have always use and it works" mentality. Which is fine, they want what they want. I can only suggest.
@@StuartsShed don't feel bad about being a hobbyist. Everyone has to start somewhere. I have known some hobbyists that are far better machinists than some professionals.
I have a friend that is a tool and die maker. The company he works for makes metal shells for automotive seating. The company was buying very low priced steel, effecting their quality, productivity and maintenance cost. Company didn't want to hear abou 44:08 the steel quality. e@TopperMachineLLC
If you could get your tool closer to the followrest, that should help with the chatter. But then there is a risk of shavings getting caught in the followrest. If you run the coolant from the opposite side, this should help to clear the shavings away from the followrest.
Josh, O.D.Pitch Micrometer.,u cut the thread to size,if the nut doesnt fit use never seez and tap the nut with a small ball pind hammer,the nut will fit the thread,get a spray bottle use thread cuttin oil I Know u own the shop u pay the bills do it your way just an idea
Need to tighten up the follow rest after each cut to makeup for follow rest wear .Push on the open side of the follow rest with a piece of wood .run a thread file along the threads? Make an adapter to fit the opposite in of the headstock to support the shaft going through the spindle to stop the shaft wiping?
Never seen or heard it addressed but it appears that spring-loaded rollers and rubbing blocks on steady and follow rest would be ideal for maintaining correct pressure without adjusting for changes in diameter etc.
I would think anything with a deliberate amount of spring designed into it would have occasions when it would hit a harmonic frequency and just bounce uncontrollably and thus then cause more problems than it solves. Though I'm sure it could be done with enough thought. I think if I had a lot of this type of work to do, a custom follow rest which had much larger area bearing pads that were bored to match the shaft that was being cut would be the way to go.
Hi Josh- One question... I did not see you cut the major diameter for the 2" thread. Are you using undersize bar? From memory, the major for a 2" thread would be something like .006" under 2". Or are you just using nominal ~2" stock and just cutting the pitch diameter a bit undersize until the nut screws on? Technically that means the threads are contacting near the crests and not really at the pitch lines. With making threads this way, you get some deformation of the male threads, hopefully elastic deformation. Anyhow, depending on how ambitious I am feeling, and how critical the application is, I do exactly the same thing. It is not by the book, but many times I don't care and it works. You probably know exactly what I am talking about, but I doubt the internet experts do. Anyhow, nice video. I always enjoy watching your new (is it still new?) lathe. ----Doozer
Thats exactly what stands in our Books here in Germany. Outside diameter of the bar has to be 1/5 of the thread-pitch smaller in diameter for not letting the crest rub in the nut. Stands in every of my 9 machining handbooks. And that was taught in technical school during apprenticeship. So do i since 45 years.
@@mftmachining I've never heard it out like that but I've always just used technical references when making threads nice to know a easy way to gage it thanks
Your bar is resonant. The chatter is feedback from the ridges left by the previous passes. You might have tried a steady rest on the far end of the bar and a damper mass of some sort wrapped around the bar, Maybe a canvas tube of wet sand spiraled around it.
I had to fix a dent in a hydraulic cylinder tube once near the closed end and it was to big to get thru the spindle so I made a bar with a plate head the size of the bore and mounted a tool bit on the face end set to size . Then mounted the cylinder tube to the tool saddle at hight and center and held the closed end on the tail stock center with a chain and bolts and left the tail stock loose so it could slide with the power feed and cylinder tube and turned the tool bar with the chuck to cut the dent out of the bore and then took a engine cylinder hone to finish the bore smooth , crude way to do the job on a lathe 14"x 36" that was to small for the job but it worked , cylinder was about 3" bore and 24" long , worked ok when re- packed .
Josh, your machining the thread with the moving follow rest took me back 64 years when I was on my apprenticeship We had a pile of rods not too dissimilar to your job to thread, and I and two other 'appies' were set up on three lathes until the job was finished. Until you showed your video, I had never seen that particular operation shown again. Takes me back. I was an Electrical apprentice, but our works manager insisted that all apprentices, went through the machine shop, fitter's benches and welding areas during our five years, and that training stood me in good stead for the next five decades. Enjoy your videos; Happy New Year.
You got a good apprenticeship. The more you learn, the better. Glad you enjoyed the video
Back in the 70’s while serving my apprenticeship, I used to turn 3ft long buttress thread form lead screws using a single point tool and a travelling steady. I remember it so vividly!
50 years making chips a few points from lead screw cutting 1st. Cutting straight in with crossslide almost doubles your tool pressure compared to compared to compound 1/2 - 1 degree less thread angle 2nd. A collar on back of spindle with 4 set screws will control whip and stiffen shaft protruding beyond chuck 3rd. Shoes on follow rest that contact more surface (we made pucks that slip over original with radius .005"-.010" over shaft size for more surface contact) rather than line contact that could mar finish if to tight. Still great job overall keeping trade alive all the best
That's why my machining instructor told us to use angle on the cross slide when cutting threads. I had always wondered why he said that, thank you.
Suggestion on preventing the tool post from moving due to cutting forces, put a sheet (about 0.125" to 0.25" or so) of soft aluminum or copper between the tool post and T-slot on the compound. The soft metal between the tool post (hard) and compound (semi hard) will slightly deform increasing friction between the tool post to compound. Same idea as using soft metal pads with a 4 jaw or 3 jaw chuck to prevent slipping and damaging the work.
Adding to small slots on the tool post T-nut side facing the top of the compound's T-slot will move the clamping force away from the edge of the compound's T-slot. This helps to prevent T-slot break out and loads the compound T-slpt towards the stronger walls instead of the T-slot edges.
Nice job on threading such a long round bar.. long thread runs with single digit thread pitch on large OD's is never easy or simple.
Just out of interest the thread I had to machine was 3inch dia, 4TPI 2start Acme plus the bronze nut , first made thread plug gauge using wires to measure then made nut to suit gauge , because the male thread was about 5 foot long so no way to offer male up to the nut ,nut was about 6ins long , took long time to make these think I had 4 sets to make was lifting screw for very large variable voltage trans former
Idea/suggestion to aid with the chatter when threading this long round bar, consider making a sleeve (bearing bronze or 12L14 steel or similar) with about 0.002"/0.003" clearance to the OD of the round bar about 2x the OD which in this example would be about 4" long with some means of attachment to the follow rest instead of the follow rest fingers. Adjust the sleeve to just clear the threading tool. This sleeve will help to reduce the "plucked string" effect of threading a long round bar. The threading tool is essentially the finger pluck on a guitar string, the length of the round bar is essentially the string being plucked. The entire round bar goes into resonance compete with waves.. some means to reduce the energy put into the round bar can and will reduce this effect.
What the traveling follow rest bushing does is to reduce the "string plucking" effect by absorbing the energy that would have gone into the long round bar causing chatter during the thread cutting operation. Lubrication of the traveling steady rest bushing is essential.
While the follow rest fingers do help prevent the Rond bar from climbing over the threading tool, the follow rest fingers does not suppress or reduce the energy transmitted into the round bar during the thread cutting operation, the traveling bushing does a better job of reducing the energy transmitted into the round bar and supports the round bar much better than just follow rest fingers when properly set up.
This is exactly what I was thinking for the next time
@1:49 Like the old saying goes, ask 10 machinists how to do something and you'll get 11 different answers. Moral is you can take many routes to get to the same destination.
Great video as always Josh! 👍👍
This saying is true of most anything. As long as the end result is good and the customer is happy, who cares how you get there.
It's just my opinion, but you are fighting torsional springback. Kind of like using a 24" socket extension with an impact gun. There is a more angular displacement in the bar the farther you are cutting away from the chuck. Also, because you have a fairly new lathe; I would check the preload on the headstock bearings. I fought chatter with my lathe and found it to be too loose. After adjusting the spindle bearing nuts, no more chatter. Just a suggestion. Oh well, if it was easy, anyone could do it! That's why you got the job. Good luck buddy!
I was fighting bad chatter also until I snuggled up the headstock a little more and I always snug the cross slide more when I’m threading or cutting
I like it when you youtubers include the sounds that you are hearing. It helps me know what I might hear.
The hardest working man in Spooner, WI strikes again ! Nice work Josh !
The 30° feed in angle can be done with the compound set parallel to the spindle as it is here in the video. Feed the compound exactly 1/2 of the amount the cross slide is moved in for each cut which produces the 30° of tool movement. The advantage, of course, is half of the cutting pressure versus cross-slide feed in only.
Actually would need to feed the compound slightly more to get a true 30° angle but the 1/2 amount keeps a slight amount of cutting pressure on the right hand thread flank for stability.
I usally use your method and it works fine ,as for the tool post i made a block and put it behind the the tool post and put acouple dowels and two socket head cap srews keeps it from turning on you.
Great suggestion.
Those chips! Amazing! I could watch them all evening. There's just something so satisfying watching chips like that!
Hi Josh, that chatter had me going a couple pf times! Good job, handeld as the craftsman you are, I allways admire your knowledge and expertise mate.
Thanks for posting, I really enjoyed watching this one, have a fine 2024.
I learned a long time ago to just plow these threads in, then fine time the chatter out. But this one had me a little worried. Luckily it came out well.
Regarding the steady, seems to me if it works, it works. I'm just a hobby guy who hopes to make a few bucks with my machines in 5-10 years once I retire, so I appreciate your output.
I do long thin walled gun barrels with a hydraulic steady rest. One thing I’ve found highly beneficial is to get your cutting tool as close to the traveling steady as is reasonable. Thanks for the video.
I was thinking the same thing......thanks for making this comment, Paul
great job i will make a suggestion when you are cutting corse threads with the cross slide set your compound parallel to the threads and if you go in 100 on the cross slide then move the compound forward half the amount of the in feed 50 that way you will be doing most of the cutting on the leading edge of the insert. just a suggestion
This will also reduce, substantially, the "creeping" of your tool!
G'day Josh. Lots of good feed back here. My take on it is 1 check live center in good condition and make your center in the bar deeper. 2 support the bar hanging out the back of the lathe, its like a tuning fork whipping around. 3 and my old stand by a piece of wood with a vee cut in the end and jam it the steady, works most time. Like what you do,
That sounded like cutting on a piece of ETD150. Can't offer anything else that wasn't already mentioned. One thing I do when cutting long winded threads like this is to back off your live center to where it is just touching and able to turn it by hand. Thanks for sharing, Ken
Ken, what is ETD150, I heard that mentioned in some videos from the UK......but have not heard the term here in the US....thanks, Paul
It's more or less 4142/45 steel that has been Q & T by a special process by LaSalle Steel Co. Google it. It's good stuff!!!@@ypaulbrown
Thanks Josh, I really enjoyed this one. I appreciate you taking the time to show us how to do it right the first time,
Looking forward already for your next one.
Huh, seems like a bit of a design oversight on the Lion lathe that you can't get the follow attached when the compound is set to 29.5? Maybe it's just me, but threading long thin threads is one of the most common reasons why I find myself needing to use a follow. So doubly odd that it won't fit when the machine is configured for doing that exact thing. Awesome vid, as always. Thanks Josh!
Josh, I know you had some minor struggles with this one, but your attitude and skill make it look easy.
I had to laugh when you made the comment about the compound angle. I'm not a machinist, but I make or repair my own parts on machines and know why the angle is set the way it is for threading.
I can't tell you how many stupid comments I get about compound angle.
That was very interesting to watch, thanks. It was good to see how you overcame the issues
Nicely done Josh, proper metal removal rates.
Not seen a 3 point travelling steady before, works well 👍.
Thanks for sharing.
I've only ever seen a 2 point followrest until I bought the lion. I really like it.
That third point basically does nothing in this case BUT would be damn handy if threading tool upside down in reverse and away from the chuck if you ever wanted to.
Nicely done with the threading rods ❤❤. Thanks for the video Josh great job 👍❤️❤️. Take care of yourself and family and friends and be Blessed ❤️.
Hey there, top, you might already know this, but I thought I might bring it up sometimes a piece of brass about 2 inches in diameter, 5 inches long or a piece of lead about the same size or a hammer handle placed in the right spot can really deal with that vibration, it ain’t a for sure, but sometimes it really works, sometimes I find less vibration if I feed towards the tailstock, my old boss used to feed towards the tailstock all the time and that’s where I picked it up, you know just turn your tool upside down and go the other way anyway looks like you’re having fun🤠
thanks Joe. I have seen that also, Paul
The lathe in the shop at my last job had a storage stand for the steady rest that was behind the headstock. The steady rest lined up with the headstock bore and could be used on long shafts to keep the stock from whipping around.
That's a great idea!
I've considered that. I have 2 steady rests for the lathe.
@@TopperMachineLLC It really works pretty well. The one I worked with was heavy, which made it difficult to move but it was stable. I was going to put retractable wheels on it, but I never got a round tuit.
I suspect it would need to be attached to the lathe somehow or bolted to the floor to keep the heavy bar from moving it around.
@@ellieprice363 The one I worked with had a serious case of gravity. It pretty much stayed put. I would have put it on rails to keep it in line with the headstock bore, but it just wasn't necessary. Plus, rails in or on the floor are a safety hazard..
If it works, do it. He makes good stuff, why argue. He's a practical machinist.
25 years, I've found short cuts and tricks to do the job. Some learned from others, some on my own. The end result is still a good product and happy customer.
😎Love how you corrected yourself on the "Way over 100%". I knew you were better than that the moment you said it. 😂😂
Non the less, a dial indicator would have proved his 100% guesses were good.
Another outstanding job.
I have never seen a thread that long single pointed before.
Was nice watching the process. 👍👍
You certainly get into some heavy duty jobs.
Have a great weekend.
Thanks. I generally turn away the small work. I like big jobs. Small jobs also come with small wallets and lots of complaints about price. Lol
@@TopperMachineLLC Josh, you got that right, in many trades too....welding, machining, art and photography, which I have been involved with since 1970
Machinist hands. I winced when you put your hand on the threads with the rod turning. Then I remembered High School machine shop instructor that would handle bare handed hot pieces coming out of the lathe or mill. he thought it was funny to hand them to the students.
Takes me back to tie bars turning for injection molding machines. Some presses were 1200 ton, oh my. The nasty chip coils are scary for sure. Nice work, thank you. Cheers
Just stand clear of the coil of death. Lol
FYI we had a milling head for the lathe and thread hob vs single point. As I recall some 50+ years later 😊 it made a pretty decent finish. Not a suggestion more of 😊a question. What do you think?
been machining for awhile now and never seen your method on the steady rest, I will have to try it, might not work on pipe though and that is what i do a lot of, I'm afraid it isn't round enough without putting a truing band on it to start with.
It works great on cold rolled and some DOM.
I did not know that you can do multiple passes to make threads. I am not a machinist, so watching your channel is always interesting and informative. That crane sure is handy. You have made some nice improvements in your shop. If I only knew what you have forgotten ........I would be smart. You done a nice job filming. How nice to see Rocky for second. It is always good to see you.
Thanks Alan. Rocky has made only small appearances this past year due to his arthritis and dementia. He doesn't spend much time in the shop.
Well done, Josh. That job will test your nerve! It made my b*** pucker just watching each pass. Thanks for letting us watch. Stay warm.
You got that right. Cutting coarse thread is always tough.
I’m gonna be honest with you guys , listening to the chatter was like chalk board 😅 . I just wanted to put my hands all over that machine to find out where that chatter was coming from.😂. Maybe applying a little pressure somewhere could’ve stopped it ? Very nice work. The nut did not have no wiggle wiggle perfect.
Considering my lack of experience with this exact operation, it came out great. But, yes, frustrating.
@@TopperMachineLLC Josh, as dumb as it seems, I was wondering if your tail stock live center had gotten slightly loose.....
I have been turning 1 inch sch 40 6061 pipe and 1 1/4 inch trying to get chatter for decorative effect.....when you want it,
it is very hard to achieve......cheers, Paul
Nice job. I really enjoyed warching...thank you Josh.
I really enjoyed seeing good single-point threading, especially the nice, meaty ones like these. Thanks for another fascinating video.
In your spare time (hohohoho) you might consider making a floor steady stand for supporting bar stock that hangs out behind the headstock. Keith Fenner used to do lots of prop shafts and had a hole in the wall for the shaft to pass through and then a floor steady with rollers in the adjacent room. Alternatively, a simple stand to which you mount your lathe's steady rest can be used the same way. Of course, if this isn't a common problem for you it probably isn't worth the effort.
The lathe has a lot of nice features, looks really solid 👍
I'm guessing, the lack of chatter at the end could be proximity to the head stock but also because of the additional pressure being put on the uncut rod after the adjustments for the threaded portion. I also wonder if putting a roller stand to lightly contact the rod sticking out of the back of the head might reduce the vibration a touch. I am no machinist but I do work on my own stuff with a small lathe and mill. I guess I need to research the compound angle thing in case I ever do try to cut threads.
Nice result. I hope the incoming weather will not be too unkind to you all.
It looks like that will mostly miss us. Still not enough to blow, I don't even have a base yet.
@@TopperMachineLLC but you have that' bad mama jamma snowblower' now....
No problem you can do the same by setting compound 1deg. less parallel but you move compound 1/2 of indeed each cut but I found it to easy to miss 1 adjustment or the other moving both each cut. Good content overall from old retire tool and die maker
That is the following rest that "sing" a song of the threats over it was rubbing. I wish a Happy New Year to you and your family.Greetings from Germany.
Hi Good to see video like this , I had to do something similar in my machinist days and chatter was always problem,I would keep the top/compound slide parallel to bed ,had the tool post dowelled to top slide to prevent it moving ,with very coarse pitch cutting full form is large chip load , as the thread got deeper I would move top slide forward/back so only cutting on one side of tool at time keep going deeperback and forth til full thread depth was reached , our customer would not except any chatter on threads
Great advise. Thanks. Since this was only my second attempt at this ever, it still came out good. Would have been better if it wasn't 1018
Oh Yes 1018 not great material at anytime another thing I just remembered was I made longer pads for the travelling steady so they would support over greater length@@TopperMachineLLC
@@TopperMachineLLC 1018, I have lots of problems getting a decent finish on that stuff.....gimme something a little harder.....to bad they did not spec 12L14....12L14 is also stronger than 1018 and has a much higher tensile strength.
Great to see the follow rest in operation. That creaping tollpost would provide an interesting thread form LOL.
I would sometimes put a slight top rake on my threading insert when plunging straight in like you were.
That way the full threading tool profile would NOT be making 100% contact each pass, because it was relieved slightly by the top rake of the threading insert. Try it next time... It couldn't hurt, especially if your hand fitting to a given nut
You seem to know better when it comes to the proper machining methods. An inexperienced machinist would run into many difficulties having watched you produce a part the way you are. I liked that you mentioned the 29-1/2 degree setting.
Nice to see some lathe work.
Wondering if the bearing surface from the steady rest rollers is wide enough. As with such a pitch, it creates pretty wide voids.
Also choosing the next lower speed would have been interesting to attempt so it could have perhaps alleviated somewhat the chatter.
I would revise the tool post. The amount of torque you put on that wrench (nut) seems quite abnormal to me.
Great job and great project to execute and a pleasure to watch from our stand point!
Thanks for sharing Josh.
God Bless.
There is so much torque transmitted during cutting that you need to tighten it enough. Big threads take a lot of torque.
Your lathe is AWSOME! A beautiful machine.
Remember that you turned the toolpost and are now cutting on both sides of the tool at the same time. Turning the toolpost as far as it will go towards the follower gets it nearer to 29.5 degrees so it is cutting on the front edge of the tool mostly.
One thing I didn't see you check after turning the toolpost, was the cutter height. I know on my lathe it does make a very slight difference.
On older and Chinese machines you will see cutter height changes. Not so with the Lion.
hello josh & it's is Randy and i like yours video is cool Thanks Josh Friends Randy
Holy crapola, you did not indicate in the steady rest or make a scratch pass to verify the thread pitch and are teaching new machinists bad habits. The threading God will punish you the next time you cut threads. :-) It is only the amateurs who find fault with what well experienced machinists do when they should be taking notes instead. Thanks for taking the time to video and edit the mega threading process.
I never do a scratch pass. In 25 years I only had one f-up and that was when I had COVID and quite sick and wasn't thinking. Needed 16tpi instead of 18. Lol.
I like how you think outside the box.
New find. Great content!
Greetings from Brooklyn
Hi Josh. I have a steady rest at the other side of the chuck at the back of the lathe to stop the bar wagging about.
40:00 I recently purchased (2) 1 7/8 8 tpi nuts , one from McMaster and one from Zoro.......
these were to be used as protectors for the spindle thread on a South Bend Lathe.....
well, the McMaster nut went on in both directions with no issue,
but the Zoro nut would only go on in one direction and then bind.....
Quality is not the same from vendor to vendor or manufacturer....
I have no idea which country they came from.....but hopefully your
client will be buying quality nuts and not blame you when they do not fit....
Paul down in Florida
Have you thought about making some kind of support stand for long stock out back of the headstock? It'd have to be pretty substantial for the stuff you work on I suppose.
Great watching along with your commentary. Unusual to see working along way from the chuck as well. Is it to reduce the amoult the bar sticks out from the rear of the spindle?
If you watch again, I showed the whip and explained the reason.
Nice to see you also have a swarf hound!
Thank you Josh!
Great video. You know, when you are getting toward the end, there is a lot of tool edge contact in the V when you are feeding straight in like that. Maybe with the compound at 29 1/2 you could feed straight in for awhile and then finish up feeding the compound in, reducing the tool contact to just the front side which might help with the chatter. Just sayin.....Dave
I did this in one other video and did it that way. Figured I'd show the other approach. I definitely prefer the 29.5 at the last several passes.
@@TopperMachineLLC I see you were banged up for room to angle the compound with the follower rest . Another way is to run the compound parallel with the bed & advance the compound a few thou for every infeed cut on the cross slide . This keeps the tool load mainly on the lead edge & reduces the load on the trailing edge . As long as the compound movements are only a few thou , it will not alter the thread profile & then just a couple of straight in feeds for the finishing cuts . Watch the lead angle on some of those threading tools as well . Cheers 👍
@@TopperMachineLLC I recently tried 15* (half of the 29.5* from dead on) at the suggestion of a machinist buddy on a tough material 1.375"-6tpi job and it worked awesome. Lightened the chip load considerably but still cut the proper form of the tool. I was surprised it worked so well.
I agree. I also move the compound forward a thou on each cut so it does the same as having it at 29.5deg, doesn't put such a load on the tool.
great comment Max Grant from down under , cheers, Paul from the other 'Sunshine State', Florida @@swanvalleymachineshop
I have the same issue with my lathe with clearance with the compound so I milled the follower
a little so I have clearance now . Not much load on a follower anyway.
Far from an expert here, but on long shafts, I had good luck supporting the outbourd end in a v-groove cut in a 4×4 set on a stand. Holding a piece of heavy brass on the working end works on some things.
Mike
looking fantastic, thanks so much for showing this great technique...
Wondering if it’s feasible to stamp a number or code into each nut and the end of the Rod to mate them up for future use ?
Josh,
Ive watched this over and over. dozens of times trying to figure the chatter out, and like you wouldnt have done anything different than what you did....your Lion lathe is way more than capable of what you are asking of it on this job.....the only remote thing i can think of would be that maybe that the live center you are using is worn and has a skosh of lateral flex in it. I might try one of Curtis at CEE's techniques in using a tailstock mounted 3 or 4 jaw rotating chuck, indicate it in, cut the thread that way and see what happens....worst would be it fixes the chatter and all you have to do is chop off the amount you were holding with the tailstock chuck.....just a thought.....so far this "terrible storm" they were forecasting has been nothing but a figment of their hype and imagination....Yaaaaaayyy for that!!!
Don
josh maybe the vibration come from steady rest,i dont sure,i just observe the vibration gone when the steady rest near the chuck,
and thanks for that awesome video,no one do that in youtube.thanks again.
Is it possible that your chatter was coming about as a result of you cutting on both faces of your cutting tool at the same time, versus having the compound set at 29.5 and cutting on just the leading edge of the cutting tool and doing all your advances with the compound.....??
That is very possible. There was a lot of torque being transmitted.
You could try changing the speed of the cut. Doing so changes the chatter frequency and will at least lessen the chatter. I've gone back and forth between selected speeds to try to eliminate it. Keep it from talking back.
Nice work, nice shop.
Follow rest. Are the inserts removable. Can you use belville springs under them to maintain the tension.
Overhang. Drop in concrete anchors sunk slightly deeper so flat head allens keep the floor level and dirt out of the threads allowing a simple angle iron support to be bolted to the floor. The bottom tube is square and has a stud up thru the middle for a tube that turns out with jacking feet on an offset so this device is only a few inches thick for easy storage. This could have 3 rollers not just to support the overhang but to dampin any chatter that goes to the overhang and back to the tool path.
I totally agree with others on checking the spindle break away rotational torque to set the preload on the bearings. Like a rear end pinion bearing 10 to just under 15 inch pounds of rotational breakaway torque for preload. I can't imagine what damage is being done to the bearing surfaces with all that chatter. Is there a neutral position where no gears are engaged to the spindle so you could use an automotive stethoscope to listen to the spindle bearings.
For a quick test. Slide a piece of bar so its balenced in the chuck. Indicator on the top cover measuring the top of the chuck. How much does it deflect when you push up and down on the bar stock.
Lastly. Imagine a knurling head that has thread shaped wheels to put the ulitmate rolled finish on threads.
Josh,
I was wondering if maybe having your tool closer to the center of the follow rest,
that the chatter may be reduced.....looking at your QCTP on the compound , it looks like
it could be moved left to get the tool closer to center on the follow rest ????
Just a comment from an occasional machinist lathe guy, I ha by no means
the experience you or many of your others viewers have.....cheers, Paul
What Rockwell hardness are the tips of the follow rest, I wouldn't mind making a set of tips for mine liken that
Keep the good work going love your videos!
hey Josh i was wondering if it would be any use to set up another following steady on the other side of the tool post or even on the right hand side of the saddle? seems to me the vibration comes in when there is a fair bit of cantilever from the supporting ends. Not critiquing in any way i think you've done a fantastic job there.
Plunge cutting threads does tear/rip up the edges wearing the follow rest plugs. You could try turning the topslide back around to 90 degrees and after some plunge cuts try the side cut method to remove chatter marks? Whilst experimenting with rev changes. Thats if theres ample room between tailstock live centre, maybe a longreach live centre would help. All the best with your business, you are very good at what you do, cheers.
Ps. Ive only recently retired from payed work but still keep active in my home shop with small steam train hobby.
Since this is only the second time I've used a follow rest in 25 years, I still have a lot to learn. Just keep at it until I find what works best or get good advice.
@@TopperMachineLLC Josh, I think you mentioned in the beginning that the follow rest had hardened jaws....
but I Amy be mistaken, but if they are, they would surely not be chewed up as others have mentioned,
did you mention the alloy of the bar stock? thanks, Paul
I'm not used to working on things where that is a simple bolt, thanks for the mind wobble [hafta expand imagination].
Very Nice, not a fan of coming down the half angle as it means using 2 dials it is a US thing as the tool shops I have worked in the UK also watching Australian videos they just get it done right the first time!!
It all depends of the application. But coming in on half the angle reduces the chance of breakage and chatter. To each their own.
Josh I think the chatter may have been because you had the compound set at 0 degrees instead of 29.5 degrees. You had no choice in the matter obviously but I was watching someone else doing some single point threading the other day on YT and they said that when they cut with a straight compound they'd advance the compound by 10% of the feed in rate. This compensated for the missing 29.5 degrees on the compound. They said that they had always used this method when straight cutting a thread and it worked out well for them. It reduces the tool pressure enormously (according to them) because a straight in cut when threading produces pressure on all sides of the cutter the deeper you go, whereas the 29.5 degree compound ensures the tool only cuts on the forward edge, they explained. Seemed very logical to me. Might be worth a try. Cheers.
Looks like I read the rate of feed in to compound percentage wrong, more like 50% apparently.
hi there well done big bolt , best to all john
What I used to do for long threading, I move tool little forward for each pass further in. So the leading edge of the tool do major cutting. It avoid the cutting vibration. The chatter comes from back side edge of cutting tool.
Interesting that the chatter gets much worse near the chuck. You would expect that in the middle. Bearings? Chuck issue?
Great Job Josh.
Going in at 29 degrees would greatly reduce the tool load and probably reduce the vibration. Also, there seems to be a resonance problem. With cylinders, I have packed the inside with clay to solve the problem and on bar I've had to adjust the length beyond the chuck, adjust speed and even located a weight along the bar. If the compound creeps, tighten the gibe.
Really like it, maybe a future shop project would be making a rearward steady when youve got the time?
Saves a bit of time throwing the steady on because it can just live there.
It's in the future plan.
I am always wondering of how do you know that the bar is exactly on center when you put it in the steady rest?
Awesome, thank you Josh!!!
So I totally understand the reason for setting the compound to 29.5 degrees. However - you ended up going straight in anyway without any problem. I have single pointed threads at both 2.9.5 and just straight in and frankly couldn't see a difference. Going to try again today - maybe my old lathe was so lightweight it just sucked whichever way. So do you generally see any kind of a difference? Do you think having to go straight in had anything to do with the little bit of chatter? I can't see why it would - seems like that is just a matter of support of the bar at the tool position.
P.S. I'm not a machinist and don't claim to be. If you're not making a living (or trying to) machining parts, then I don't think the term machinist really applies. I'm OK calling myself an amateur or a hobbyist. The machinists at work don't laugh at me too much. 🙂
Since I had to go strait in, I was putting cutting pressure on both sides of the insert. It is always best to go in at 29.5, as you are only cutting on one side. I think most of that chatter was from cutting both sides of the thread instead of the leading edge. I had double the tool pressure trying to lift the bar. The other issue was the material, but I couldn't convince the customer to go to something better. The old "This is what we have always use and it works" mentality. Which is fine, they want what they want. I can only suggest.
@@StuartsShed don't feel bad about being a hobbyist. Everyone has to start somewhere. I have known some hobbyists that are far better machinists than some professionals.
I have a friend that is a tool and die maker. The company he works for makes metal shells for automotive seating. The company was buying very low priced steel, effecting their quality, productivity and maintenance cost. Company didn't want to hear abou 44:08 the steel quality. e@TopperMachineLLC
@@jackgreen412 Engineers, that is why we love them......haha
If you could get your tool closer to the followrest, that should help with the chatter. But then there is a risk of shavings getting caught in the followrest. If you run the coolant from the opposite side, this should help to clear the shavings away from the followrest.
Thanks for the video. What insert were you using?
Josh, O.D.Pitch Micrometer.,u cut the thread to size,if the nut doesnt fit use never seez and tap the nut with a small ball pind hammer,the nut will fit the thread,get a spray bottle use thread cuttin oil I Know u own the shop u pay the bills do it your way just an idea
Need to tighten up the follow rest after each cut to makeup for follow rest wear .Push on the open side of the follow rest with a piece of wood .run a thread file along the threads? Make an adapter to fit the opposite in of the headstock to support the shaft going through the spindle to stop the shaft wiping?
Never seen or heard it addressed but it appears that spring-loaded rollers and rubbing blocks on steady and follow rest would be ideal for maintaining correct pressure without adjusting for changes in diameter etc.
I've considered that, but I don't know if it would work. Too many variables with springs. May be a good idea for a future video.
I would think anything with a deliberate amount of spring designed into it would have occasions when it would hit a harmonic frequency and just bounce uncontrollably and thus then cause more problems than it solves. Though I'm sure it could be done with enough thought.
I think if I had a lot of this type of work to do, a custom follow rest which had much larger area bearing pads that were bored to match the shaft that was being cut would be the way to go.
Do they make steady rests that are heavy / weighted, and can be used out the back of the machine to keep it from whipping?
Hi Josh- One question... I did not see you cut the major diameter for the 2" thread. Are you using undersize bar? From memory, the major for a 2" thread would be something like .006" under 2". Or are you just using nominal ~2" stock and just cutting the pitch diameter a bit undersize until the nut screws on? Technically that means the threads are contacting near the crests and not really at the pitch lines. With making threads this way, you get some deformation of the male threads, hopefully elastic deformation. Anyhow, depending on how ambitious I am feeling, and how critical the application is, I do exactly the same thing. It is not by the book, but many times I don't care and it works. You probably know exactly what I am talking about, but I doubt the internet experts do. Anyhow, nice video. I always enjoy watching your new (is it still new?) lathe. ----Doozer
Thats exactly what stands in our Books here in Germany. Outside diameter of the bar has to be 1/5 of the thread-pitch smaller in diameter for not letting the crest rub in the nut. Stands in every of my 9 machining handbooks. And that was taught in technical school during apprenticeship. So do i since 45 years.
@@mftmachining I've never heard it out like that but I've always just used technical references when making threads nice to know a easy way to gage it thanks
Your bar is resonant. The chatter is feedback from the ridges left by the previous passes. You might have tried a steady rest on the far end of the bar and a damper mass of some sort wrapped around the bar, Maybe a canvas tube of wet sand spiraled around it.
I had to fix a dent in a hydraulic cylinder tube once near the closed end and it was to big to get thru the spindle so I made a bar with a plate head the size of the bore and mounted a tool bit on the face end set to size .
Then mounted the cylinder tube to the tool saddle at hight and center and held the closed end on the tail stock center with a chain and bolts and left the tail stock loose so it could slide with the power feed and cylinder tube and turned the tool bar with the chuck to cut the dent out of the bore and then took a engine cylinder hone to finish the bore smooth , crude way to do the job on a lathe 14"x 36" that was to small for the job but it worked , cylinder was about 3" bore and 24" long , worked ok when re- packed .
Basically you turned your lathe into a horizontal boring mill. Nothing wrong with that. Actually shows your skill as a machinist. Good job 👍
Follow rests don't get enough love, I think.
Hey Josh , good one ! That thread lever looks a tad on the awkward side esp if coming to a shoulder or want to bail out in a hurry ! 👍
Why not use an indicator when adjusting the steady rest? Just curious, thank you.
I've never found much benefit to using an indicator.
@@TopperMachineLLC Thank you.
What soluble coolant are you using on the lion? It wets onto the metal better that mine, which tends to bead up and not coat like yours.