The thing to remember is the one who never makes a mistake is the one who never does any of the work despite the fact they are more than willing to make sure to point out everything you are doing wrong however, their mistake is that they are not or cannot do the work. Always enjoy your content and learn from you repeatedly; keep doing what you do, it is not broken!
Mike here in Lincoln, Nebraska. Retired anesthesia provider. Took up machine work in my retirement years. I look forward to each and ever video you post.Thanks for being my new professor in a hobby i really enjoy. Best wishes. Mike
My mom was an anesthesiologist. She could run the anesthesia machine just fine but every time we would go to her house the clock on the VCR was blinking 12:00 because she couldn't figure out how to reset it; LOL. She was never good with instruction manuals. She would make the vendor sit there for hours and explain every bit of equipment on the cart.
This is my first comment to your videos. I have been so envious of you and your tools. I have so many hours of watching you and have been jealous of your skill. My eighteen year old cat and I sit together and watch you channel together. I am a 70 year old industrial maintenance mechanic and wish I had taken lath classes when I was younger. Good on you.
Great format, simple vid, but has a good layout and it's always enjoyable watching chips getting thrown and hearing the thought process. You rock dude, thanks for sharing your shop time with all us sinners.
You sir are a master machinist, from one machinist to another you are one of the most skilled machinist i have ever seen, we are a dying breed. Keep up the good work
I almost jumped to commenting when I heard the tool bit scratching on it's way out at about 06:30... Good thing I was patient until the end of the video when you mentioned it yourself. Thanks for the last hour of video today!
Damn I love this channel! Just had some Acme single start 1-1/2 4's made at my local shop both left and right. Love seeing what I order made and the talent it takes to make them! Great job.
Now that is a big reason we like to watch your channel, you do good work and you like to explain to us non machinist what it is all about. And when you go to do a job your machine is clean not like some of the others we see with swarf and chips all over the machine and crud on the floor. Keep up the good work and we will be here as long as you are.
It is definitely tough to get an acme thread to a tight tolerance less than .003". I do the math and when the internal thread is to size, I just continue taking spring passes until the shaft fits or the tool is no longer taking material off. Internal acme can be tough especially if your boring bar starts to get any flex in it. Job well done sir. I constantly am learning tricks from your channel
I do this all the time Adam. I'll machine a part in my shop and call it good enough all while in the back of my mind I know I'm not happy with it. Days later I'll be redoing it. Good stuff, I love the sound of those chips being cut.
Hi Adam, your acme threading videos are great! Just the information I need to get my 1934 South bend 9 back in shape. Cross feed is really sloppy. Your content is always so easy to understand. I'm a retired welder with a small shop in the garage. Again thank you for all the information. Be well!!
Great job Adam , just love your videos they are so informative . The way you share your experience and your mistakes,I have learned so much from you over the years I've watched your channel ,your a natural in front of the camera . Look forward to the next show . Dare I say it ...will we see a new acme screw for the new nut ? Hope so ,that would be a cool project . Thanks for sharing For the 2 that thumbed down this video ....walk on guys eh
You’ve got a pair of lovely shiny new nuts there! This was enjoyable to watch, I think you made the right call re-doing it rather than re assembling the machine and it bugging you forever!
The 1st one I ever did... Was for a small cheap chinese vise that my friend had. I got about 3/4 finished with the thread. I was usin a mild steel BB because I didnt have any better material to make it out of. I ended up twistin off the BB and kinda wrecked the thread. I simply made a new BB and picked up the thread an kept on the same piece. It had a really tight place in it. I used some lapping compound on it and worked it back and forth a bunch until it went through. Cleaned it all up good in some solvent and gave it back to my friend. He loved it! Took it to work an showed his boss what a wonderful fit I had made :)
I've done a few repairs on old vises that had some really odd ball acme and square threads. In the end, it always seemed to work out better grinding the tool to fit shaft itself instead of grinding it to the gauge. I'm sure you already checked but it might help somebody else. Sometimes there's quite a bit of difference from a standard to a worn shaft, produced to, who knows what spec. this is especially true if you are trying to match Chinese metric trapezoidal thread shafts.
Hi Adam, Machinery Handbook has a section on thread cutting and includes some tables of helix angles for various thread pitches. If the leading edge of your cutting tool is less than the angle in the table then your tool will rub. Best wishes Mike M.
I liked the comment (in the comments) about grinding the tool to fit the screw, seemed to make a lot of sense. I'd be interested to hear your thoughts on the pros and cons of making a new screw, there sure is a lot of people asking for it :) Great content as always bro.
I'm not a machinist, but I'm guessing that the amount of wear along the length of the screw was varied enough that you couldn't get a tool shape that accounted for those different amounts...
As Adam found on the first nut he threaded, when you are cutting coarse threads on a small diameter (or finer threads with multiple starts as on a valve stem for instance) you have to keep in mind that the helical angle of the thread may be such that you need more cutting lip relief than you normally use to prevent the cutting tool from dragging. Excellent video on how to set up for Acme threading. You may not need to do it often, but if you look at the price of a 1/2"-10 left hand Acme tap you will be glad you know how.
Great result - I hate internal threading - trying to get spot on! I guess a brass or bronze nut might be better with regard to wear being more biased to that then the leadscrew. However, good lube with the ductile one and long life should be guaranteed. Nice job Adam.
Great job Adam, you’re the best! Man, this Monarch is a beast. Really satisfying to hear and see those chips coming out. Well, I guess it calls for a barbecue or some shrimp, doesn’t it?
Hello Abom79, I just found your channel today and I enjoyed it...trip down memory lane. I'm now retired but every once in a while I get called back by my former company to do some machining or what not, something they don't have the time to do. Anyway, if I may make a comment. I have also done a few acme threading before(internal/external) and I found that it is better to start off with a slightly smaller tip on the tool bit meanwhile that you are making the initial cuts. You can enlarge the thread by side to side cut then finish off with another tool bit. Just my experience.
Don't feel bad ,I've always learned more from my mistakes, than when it turns out right. I know exactly how you feel with the first nut,some jobs haunt me until I do it right or better. 78 years and still not anywhere close to perfect. Sometimes close is as good as you can get.
Right James... Its not so much being a perfectionist, its knowing you CAN do better & you want to do it to the best of YOUR ability. Never settle for less than your own ability (which will increase with experience) Chasing perfectionism is a fools game. 😎👍☘
Hi! Great content! I enjoy all your videos for the wealth of information and experience you share with us viewers. Regarding the shaper project, I wonder if you have considered making a new screw to go along with the new nut you have made. As you mentioned in previous videos the old one has some uneven wear and slightly bent or twisted areas. Good luck with whatever you decide.
Adam: Great video and great attitude about learning from your mistakes and looking forward rather than dwelling on them. Keep 'em coming (the vids, that is!)
Not just when you're cutting Acme threads, any time you are cutting internal, regular thread or even just boring, you have to keep in mind having enough bottom clearance on your cutter or it will rub on the work piece and not cut correctly. When you are internal, the work is getting closer to the tool after the cut, when you are making an external cut the work is going farther away from the tool after the cut.
Don't Know to much about making acme threads,But would accuracy improve by reducing cutting speed to back gears?What about lubrication?Whats your thoughts on this?Thank's,Norm.
If you wanted to make a third nut (and I'm sure you don't want to) you could use the first nut as a lap on the tight parts of the screw and get them closer in size to the worn part of the screw. Then a new nut could be tighter on the worn part, since the lapping would rub the starting end of the screw down a little.
The wear is not on the diameter, its on the thread flanks, resulting in "thinning" of the threads at the high-wear point... why would you want to end up with the complete shaft with thinned down threads ? If wear is bad enough, a new shaft is the way to go, but I personally could live with a significantly reduced backlash figure in the wear zone... at least for a while 🙄😂 And I wouldnt bring lapping paste NEAR an internal / external thread combo like that because you will NEVER completely clean it off, resulting in continuous "lapping" & subsequent high wear when back in service.. 🙄 😎👍☘
Test if You have clearance on the underside of the tool bit, by fitting it into the old nut. I put the boring bar on rollers, the nut in a V-block - and aligned their centers, with a calculator and shims. I made a nut for a cheap aluminum drill vise, which broke on the first attempt after I made the nut. At least, I learned a few about boring bar tool bit clearance. LOL! Nice shaper videos, Adam! Thanks..;)
I like this second video. It shows you aren't obsessed with perfection, but I'll have to say you come pretty damned close more often than not! Good effort and good results.
Great acme thread teaching series! I have to say on some of my thread matching when getting close and afraid to take just one more cut I have used lapping compound to get my finished fit.
Xavier Ancarno Better then this is not possible. The tolerance at the end of the screw was 1/1000 and in the middle 3/1000. So making a third nut is not useful, because the differance in play is in the screw. The only thing that will make the tolerance smaller will be a new screw.
If you got the .001" that you wanted for backlash on the worn section than you would have been too tight for the non-worn section. In my opinion you ended up with a 100% success on that job. Great video, thank you!
c'mon, Adam. WE ALL KNOW you'll end up making a whole new screw... LOL i'm just kidding, we really trust your judgement and got no doubt you know exactly what you're doing. thanks for sharing and have a nice week!
I have seen some machinists make the threading tool out of round stock, then they rotate it in the boring bar to match the helix angle of the thread. This avoids clearance problems. Nice job.
Excellent video Adam... Thanks for the comparison between the two. (and showing that you don't get it right the first time all the time ;) ) Real world.
@Abom79 Just a suggestion on them nuts. You should dremel tool the start of the thread like the old brass one was done. The thin taper at the end of the thread will fatigue crack in a short amount of time. I've had this happen to me and the broken chip jammed up my cross slide. I had to cause more damage by needing to force the jammed thread apart to clean it. I can see that the original nut got the same fatigue cracking that happened to me at both ends. Time stamp 9:44
Theoretically, that three thou clearance should be just enough room for an oil film on both sides depending on the viscosity. What does that feel like in the real world of machines? :)
Another excellent video, the extraordinary being taught by life to do what is correct, not to seek easier solutions to the task at hand, humbling and fulfilling together.
Excellent job Adam,I always enjoyed threading on the lathe.Quick question though,what is your bench top made from,is that butcher block wood or just plywood.
As with ALL threads, you have to hold back pressure on your longitudinal wheel to prevent the bobble at your entrance and exit of the material. Also, it's a lot less nerve wracking to thread away from the chuck than it is to thread into the chuck.
Nice work Adam. Those dang internal acme's can really give you a hard time. I threaded a nut a bit bigger then these one time and it had a hard spot in it. But it didn't reveal itself until I was about .030" away from finish size. Kept breaking my tool. Don't buy the Chinesium !!! It might look good, but you don't know whats in it ! Finally we had to buy an acme tap to get through it. Dam frustrating. Cheer's buddy...
I have a question Adam or another viewer might be able to answer: could the nut be machined to the worn mid-shaft threads and heated / expanded to be spun pasts the unworn threads at shaft end? Could the original nut be split and halves drilled & tapped for push / pull bolts?
....no !!! 😏 It wouldn't work Steve... a new nut AND shaft is the real answer here but if the wear isn't "too" bad the reduction in backlash from the new nut alone will often suffice. Backlash is present even in new screw/nut combos... learning to deal with it is a part of the machinists training, e.g. if you turn the feedscrew inwards and overshoot your mark by say 20 thou on the dial.... you don't just back off the 20 thou..if backlash is say 8 thou you have in reality only backed out 12 thou... you need to back out say 50 thou & then come back in to hit your spot...🙄 It sounds tedious but in reality it becomes second nature to a machinist & we don't even have to think about it when working ... 😎👍☘
Adam, Thanks for the video! You'll have the G & E back making accurate chips soon. I noticed you upgraded the Monarch with the official "Doubleboost" light! Thanks for the SNS as well! Have a good one! Dave
Nice to highlight what didnt work out so well Adam, always learning and relearning what weve forgotten. Can really see a marked difference in the finish of the threads in the second nut. Cam imagine its always some sort of compromise on a used screw, no point in having the 'perfect' nut that wont go on or bind further up the thread. Reckon that .003" will work out great on the shaper, dunno what mine is but im sure its north of .030" lol. I havent done it yet but remember reading somewhere an account of a goto guy for turned to fit threads. iirc he ran the compound inline with the spindle and rough plunge cut first, then finished with an undersized tool. When he was to depth hed then take the final cuts to fit using the compound to advance the cutter, ie just cutting one face of the thread to sneak up on the final fit. Ill give it a go when I get a mo. Cheers
lol, you been there already. th-cam.com/video/P9-fH3fS724/w-d-xo.html Ive been thinking about using square form threads also, the one in my compound is square form.
Good work. Sounds like there's a slight chatter when making those cuts. Is that due to the grain structure of the material or because the cutter has to be so far out from the tool post?
Long boring bars will do that with the high cutting area encountered in acme threads... taking a number of "spring-passes" without adding feed will usually clean up the chatter marks... also helping to sneak up on the fit... as Adam did in this vid.. 😎👍☘
Looking Good! But the time you finish working all the kinks out of that shaper it's going to be better than new. I was thinking (I know, no good can come of that) could you have made a spring loaded anti backlash nut. Would it have been worth the effort?
Learning to live with backlash is part of our training as machinists... & by that I don't mean ignoring it, but COMPENSATING for it in the operation of our machinetools...even NEW screw/nut combos will have a certain amount of backlash. 😎👍☘
Adam I guess you need to build a new screw and nut for what you are looking. And it will be really interesting to watch and a great video for channel. Great video adam.your monarch carriage is really smooth . Im strictly telling you we need some abom size machining content it has been so long since you show us something on that pacemaker. Thank you for a great video
It's a good thing, to make mistakes once in a while. it will make you smarter along the way. If one never makes mistakes, it's always because one is lazy and make nothing. everything mankind have, is because smart people made a lot of mistakes and learned from them. Thanks for a great tube. :-)
I can see you making a new screw Adam man? you know it has to be right, your the man Adam machine work is your game the thread is good at the end where there is no ware on the screw, so the answer is make a new one, as Keith Fenner says get it dun.
on your paperweight nut, couldn't you just take the bad side and face it down a bit in the lathe to make it look better or is there an overall length that you need to keep?
Great work Adam. I have to do an acme nut soon for my (small Southbend type) lathe, and its great to see something done so well. I have 35 thou backlash!!
Just the slights bit of chatter on the first thread. I have one of those bars, and it gives me the same signature! That second one does look better. Thanks for shooting that head on of the tool. Very informative.
Yup, I have that same style and size bar. When I was cutting the 2.125 x 5 threads on my face plate, it did that exact pattern. They are a bit thin and whippy, so lots of spring passes.... I didn't expect to see them on his though. I mean, he's a REAL machinist.... I don't even play one of TV!!!!
It doesnt matter,even best threading bars will flex under certain conditions-some more some less but they all do.Alot of focrce is applied when cutting profile threads.When you do normal boring with boring bar it tends to push bar down,When you cut threads all the force is applied to the left(or if you put threading bar upside down and thread in reverse like some people it will push it to right and push bar to the left) will tend to push threading bar to your right. Will there be chatter depends on thickness of the threading bar which is determined by the hole you are threading -aka will it fit inside hole.Also the depth of cut and the pitch -higher pitch produces higher chatter so you need to lower your depth of cut and do more passes and lower your rpms.Material that you are cutting is one of factors -in bronze which is soft is easier to cut profile threads than in steel since it is softer. First passes can be done on higher speeds and depths then you reduce it as knife goes in and cuts with more surface. Geometry of knife-relief and rake angle have a lot to do whether there will be chatter or not.generaly you want negative angles for ease of cutting. it sounds complicated but with experience you get to know which speed ,knife geometry and depth work best for type of job you are doing.Google helps also.
Perfect timing I'm getting ready to try making some new lead nuts for my little old clapped out Bench Master milling machine and I'm by no means any more than a amateur hobby machinist but I have spent enough time around people with more experience that I'm more than up for giving it a go. The original nuts were brass was thinking about making them out of ductle any thoughts on the better choice for material?
Adam, somebody's comment just got me to thinking. Since the tool head is going to be vertical the vast majority of the time, and so gravity is pulling down on the entire assembly as well, could you possibly grind your shaper tool bits such that your leading edge is not perfectly square with the tool holder, but instead has a bit of a rake, top of leading edge towards the ram, and not much of a rake at all, like 1-2 degrees? What this is trying to do is that now the very bottom of the leading edge makes contact first and the cutting now progresses up the leading edge and results in the work-piece exerting a slight tug on the bit as its cutting, just like on a dovetail/spring bit theoretically, so now the cutting working with the tool-head weight in keeping backlash minimized instead of against it. I would be interested in hearing your thoughts on this in more detailed discussion on shaper toolbit grinding.
Adam, it seems like your problem now is that you need to make a new screw. You made a form tool according to your gauge shape but the shape of the thread on the screw obviously deviates from the correct shape. You can never achieve your target backlash with a worn screw. Also, if you are having a hard time with that last thread because the tool isn't fully buried in the material, why not make the nut an extra thread longer and then face it off later?
I think that he would need a follow rest for the cross slide to limit the deflection. Cutting Acme thread creates quite a bit of tool pressure. That rod is hardened so he would probably need to heat treat the rod and then hard turn it to finish. That's a lot of work.
Adam Just a thought, but maybe machine the nut tight, then using valve grinding compound lap the nut to the screw to get the best fit and least backlash?? John
Is it possible to use one of the old nuts with some diamond grinding paste to polish out the tight sections of the thread? Either that or chase a short section multiple times, adjusting the 4 jaw repeatedly to make the section concentric as you extract it?
The thing to remember is the one who never makes a mistake is the one who never does any of the work despite the fact they are more than willing to make sure to point out everything you are doing wrong however, their mistake is that they are not or cannot do the work.
Always enjoy your content and learn from you repeatedly; keep doing what you do, it is not broken!
Mike here in Lincoln, Nebraska. Retired anesthesia provider. Took up machine work in my retirement years. I look forward to each and ever video you post.Thanks for being my new professor in a hobby i really enjoy. Best wishes. Mike
My mom was an anesthesiologist. She could run the anesthesia machine just fine but every time we would go to her house the clock on the VCR was blinking 12:00 because she couldn't figure out how to reset it; LOL. She was never good with instruction manuals. She would make the vendor sit there for hours and explain every bit of equipment on the cart.
This is my first comment to your videos. I have been so envious of you and your tools. I have so many hours of watching you and have been jealous of your skill. My eighteen year old cat and I sit together and watch you channel together. I am a 70 year old industrial maintenance mechanic and wish I had taken lath classes when I was younger. Good on you.
Great format, simple vid, but has a good layout and it's always enjoyable watching chips getting thrown and hearing the thought process. You rock dude, thanks for sharing your shop time with all us sinners.
Adam, thank you. I feel like I am standing right beside you. You are a very talented teacher not to mention an outstanding machinist.
You sir are a master machinist, from one machinist to another you are one of the most skilled machinist i have ever seen, we are a dying breed. Keep up the good work
I almost jumped to commenting when I heard the tool bit scratching on it's way out at about 06:30... Good thing I was patient until the end of the video when you mentioned it yourself. Thanks for the last hour of video today!
I'm still waiting for that new screw we know your going too make. Great work Adam.
You are a specialist. It is nice to see you operate.
Great content Adam. Love seeing the work you're doing to make it right again!
Damn I love this channel! Just had some Acme single start 1-1/2 4's made at my local shop both left and right. Love seeing what I order made and the talent it takes to make them! Great job.
Thanks for sharing! You do good work! I enjoy watching all your videos!
Now that is a big reason we like to watch your channel, you do good work and you like to explain to us non machinist what it is all about. And when you go to do a job your machine is clean not like some of the others we see with swarf and chips all over the machine and crud on the floor. Keep up the good work and we will be here as long as you are.
It is definitely tough to get an acme thread to a tight tolerance less than .003". I do the math and when the internal thread is to size, I just continue taking spring passes until the shaft fits or the tool is no longer taking material off. Internal acme can be tough especially if your boring bar starts to get any flex in it. Job well done sir. I constantly am learning tricks from your channel
Adam knowing you through all your fantastic videos, it surprised me that you didnt redo the screw as well. Anyway fantastic job man.
I do this all the time Adam. I'll machine a part in my shop and call it good enough all while in the back of my mind I know I'm not happy with it. Days later I'll be redoing it.
Good stuff, I love the sound of those chips being cut.
Hi Adam, your acme threading videos are great! Just the information I need to get my 1934 South bend 9 back in shape. Cross feed is really sloppy. Your content is always so easy to understand. I'm a retired welder with a small shop in the garage. Again thank you for all the information. Be well!!
Piece by piece, making the old work like new again. Your grandkids are really going to like that shaper!
Great job Adam , just love your videos they are so informative . The way you share your experience and your mistakes,I have learned so much from you over the years I've watched your channel ,your a natural in front of the camera . Look forward to the next show . Dare I say it ...will we see a new acme screw for the new nut ? Hope so ,that would be a cool project .
Thanks for sharing
For the 2 that thumbed down this video ....walk on guys eh
Love it, true craftsman. "It's not enough to just get it done, you've gotta get it right" Well done!
Adam. You are clearly a badass machinist. Why not make a new screw to get the backlash to where you like?
The th reads look great Adam. You are like me I am very particular about how my work looks and it being right. Good job Buddy.
You’ve got a pair of lovely shiny new nuts there!
This was enjoyable to watch, I think you made the right call re-doing it rather than re assembling the machine and it bugging you forever!
I love the hand polish on the lathe nobs, It's something that can't be replicated with ease.
Monarch knobs are chromed on the ends. But yeah, it makes a nice patina.
They have literally been hand polished for generations.
The 1st one I ever did...
Was for a small cheap chinese vise that my friend had.
I got about 3/4 finished with the thread.
I was usin a mild steel BB because I didnt have any better material to make it out of.
I ended up twistin off the BB and kinda wrecked the thread.
I simply made a new BB and picked up the thread an kept on the same piece.
It had a really tight place in it.
I used some lapping compound on it and worked it back and forth a bunch until it went through.
Cleaned it all up good in some solvent and gave it back to my friend.
He loved it!
Took it to work an showed his boss what a wonderful fit I had made :)
I've done a few repairs on old vises that had some really odd ball acme and square threads. In the end, it always seemed to work out better grinding the tool to fit shaft itself instead of grinding it to the gauge. I'm sure you already checked but it might help somebody else. Sometimes there's quite a bit of difference from a standard to a worn shaft, produced to, who knows what spec. this is especially true if you are trying to match Chinese metric trapezoidal thread shafts.
Hi Adam, Machinery Handbook has a section on thread cutting and includes some tables of helix angles for various thread pitches. If the leading edge of your cutting tool is less than the angle in the table then your tool will rub. Best wishes Mike M.
I always look forward to your vids. Great content and it comes from a man I could call friend. Thank you for all the time you put into your vids.
Just got here. I KNEW you were going to make another nut using the lessons learned from the first. Nice!
I liked the comment (in the comments) about grinding the tool to fit the screw, seemed to make a lot of sense. I'd be interested to hear your thoughts on the pros and cons of making a new screw, there sure is a lot of people asking for it :) Great content as always bro.
I'm not a machinist, but I'm guessing that the amount of wear along the length of the screw was varied enough that you couldn't get a tool shape that accounted for those different amounts...
As Adam found on the first nut he threaded, when you are cutting coarse threads on a small diameter (or finer threads with multiple starts as on a valve stem for instance) you have to keep in mind that the helical angle of the thread may be such that you need more cutting lip relief than you normally use to prevent the cutting tool from dragging.
Excellent video on how to set up for Acme threading. You may not need to do it often, but if you look at the price of a 1/2"-10 left hand Acme tap you will be glad you know how.
Great result - I hate internal threading - trying to get spot on! I guess a brass or bronze nut might be better with regard to wear being more biased to that then the leadscrew. However, good lube with the ductile one and long life should be guaranteed.
Nice job Adam.
Great job Adam, you’re the best! Man, this Monarch is a beast. Really satisfying to hear and see those chips coming out. Well, I guess it calls for a barbecue or some shrimp, doesn’t it?
Hello Abom79, I just found your channel today and I enjoyed it...trip down memory lane. I'm now retired but every once in a while I get called back by my former company to do some machining or what not, something they don't have the time to do. Anyway, if I may make a comment. I have also done a few acme threading before(internal/external) and I found that it is better to start off with a slightly smaller tip on the tool bit meanwhile that you are making the initial cuts. You can enlarge the thread by side to side cut then finish off with another tool bit. Just my experience.
Don't feel bad ,I've always learned more from my mistakes, than when it turns out right.
I know exactly how you feel with the first nut,some jobs haunt me until I do it right or better.
78 years and still not anywhere close to perfect. Sometimes close is as good as you can get.
Right James...
Its not so much being a perfectionist, its knowing you CAN do better & you want to do it to the best of YOUR ability. Never settle for less than your own ability (which will increase with experience)
Chasing perfectionism is a fools game. 😎👍☘
Hi! Great content! I enjoy all your videos for the wealth of information and experience you share with us viewers.
Regarding the shaper project, I wonder if you have considered making a new screw to go along with the new nut you have made. As you mentioned in previous videos the old one has some uneven wear and slightly bent or twisted areas.
Good luck with whatever you decide.
Adam: Great video and great attitude about learning from your mistakes and looking forward rather than dwelling on them. Keep 'em coming (the vids, that is!)
It's a great feeling when you go from impossible to perfect in a single spring pass.
And the opposite is true John... when what you thought was a light spring cut bites 5 thou off...grrr ... 🙄😩😩😩
😎👍☘
You can always make another shaft in the future. Ya gotta know when too call it good! LOL Great job Adam...
Not just when you're cutting Acme threads, any time you are cutting internal, regular thread or even just boring, you have to keep in mind having enough bottom clearance on your cutter or it will rub on the work piece and not cut correctly. When you are internal, the work is getting closer to the tool after the cut, when you are making an external cut the work is going farther away from the tool after the cut.
its lead angle + clearence on the side of the tool .
Looks like everyone else wants you to make a new screw. Pretty cool vid. Btw what happened to the lead hammer you and Keith poured three years ago
Don't Know to much about making acme threads,But would accuracy improve by reducing cutting speed to back gears?What about lubrication?Whats your thoughts on this?Thank's,Norm.
If you wanted to make a third nut (and I'm sure you don't want to) you could use the first nut as a lap on the tight parts of the screw and get them closer in size to the worn part of the screw. Then a new nut could be tighter on the worn part, since the lapping would rub the starting end of the screw down a little.
The wear is not on the diameter, its on the thread flanks, resulting in "thinning" of the threads at the high-wear point... why would you want to end up with the complete shaft with thinned down threads ? If wear is bad enough, a new shaft is the way to go, but I personally could live with a significantly reduced backlash figure in the wear zone... at least for a while 🙄😂
And I wouldnt bring lapping paste NEAR an internal / external thread combo like that because you will NEVER completely clean it off, resulting in continuous "lapping" & subsequent high wear when back in service.. 🙄
😎👍☘
Test if You have clearance on the underside of the tool bit, by fitting it into the old nut. I put the boring bar on rollers, the nut in a V-block - and aligned their centers, with a calculator and shims. I made a nut for a cheap aluminum drill vise, which broke on the first attempt after I made the nut. At least, I learned a few about boring bar tool bit clearance. LOL! Nice shaper videos, Adam! Thanks..;)
I like this second video. It shows you aren't obsessed with perfection, but I'll have to say you come pretty damned close more often than not! Good effort and good results.
Great acme thread teaching series! I have to say on some of my thread matching when getting close and afraid to take just one more cut I have used lapping compound to get my finished fit.
I have the feeling you will make a third attempt off camera.
Perfectionist 👌
Xavier Ancarno
Better then this is not possible. The tolerance at the end of the screw was 1/1000 and in the middle 3/1000. So making a third nut is not useful, because the differance in play is in the screw. The only thing that will make the tolerance smaller will be a new screw.
My thoughts exactly...
If you got the .001" that you wanted for backlash on the worn section than you would have been too tight for the non-worn section. In my opinion you ended up with a 100% success on that job. Great video, thank you!
Adam wanted the .001" clearance on the good portion of the thread .. he hit .003" after the spring cut took a tiny bit more than anticipated... 😎👍
c'mon, Adam. WE ALL KNOW you'll end up making a whole new screw... LOL i'm just kidding, we really trust your judgement and got no doubt you know exactly what you're doing. thanks for sharing and have a nice week!
I have seen some machinists make the threading tool out of round stock, then they rotate it in the boring bar to match the helix angle of the thread. This avoids clearance problems. Nice job.
I've done this.. it works well & with small thread diameters it helps in reducing the amount of "meat" you grind off the cutting tip... 😎👍☘
Excellent video Adam... Thanks for the comparison between the two. (and showing that you don't get it right the first time all the time ;) ) Real world.
@Abom79 Just a suggestion on them nuts. You should dremel tool the start of the thread like the old brass one was done. The thin taper at the end of the thread will fatigue crack in a short amount of time. I've had this happen to me and the broken chip jammed up my cross slide. I had to cause more damage by needing to force the jammed thread apart to clean it. I can see that the original nut got the same fatigue cracking that happened to me at both ends. Time stamp 9:44
Nice work Adam. I'm wondering if you have a follower rest for the Monarch for when you decide to make a new screw. Jeff
Learning a lot from these vids.
Looks like you hit it DEAD NUTS..LOL.. You nailed it the second time man..THUMBS UP !!
So if the original threaded rod is warped or bowed why not machine a new one? Is it just a case of this is good enough or something else?
Awesome channel, keep up the good videos i love them
Great camera placement, love seeing exactly what you are doing on the apron!!
Your camera work is getting better all the time. This one is as professional is it gets!
Theoretically, that three thou clearance should be just enough room for an oil film on both sides depending on the viscosity. What does that feel like in the real world of machines? :)
on your last pass,you took 2-1/2 thou. As close as the screw came to going thru, I think I would have gone a thou at a time. How did you know?
I can see you making a new screw in your future. :) Great videos ABOM.
Another excellent video, the extraordinary being taught by life to do what is correct, not to seek easier solutions to the task at hand, humbling and fulfilling together.
Excellent job Adam,I always enjoyed threading on the lathe.Quick question though,what is your bench top made from,is that butcher block wood or just plywood.
Well done Adam. Sometimes you just gotta hold your mouth right to get er done.
You looking better every time I see another one of your vids Abom
As with ALL threads, you have to hold back pressure on your longitudinal wheel to prevent the bobble at your entrance and exit of the material. Also, it's a lot less nerve wracking to thread away from the chuck than it is to thread into the chuck.
Adam can't you make a new screw? I imagine that the difference in backlash is because of the wear/bent/stretch.
Nice work Adam. Those dang internal acme's can really give you a hard time.
I threaded a nut a bit bigger then these one time and it had a hard spot in it. But it didn't reveal itself until I was about .030" away from finish size. Kept breaking my tool. Don't buy the Chinesium !!! It might look good, but you don't know whats in it ! Finally we had to buy an acme tap to get through it. Dam frustrating. Cheer's buddy...
Man that’s just a bad day in the shop right there.
I loved this acme thread turning videos!
Question: is there a way to polish (or fine grind) this nut thread with the lathe?
I have a question Adam or another viewer might be able to answer: could the nut be machined to the worn mid-shaft threads and heated / expanded to be spun pasts the unworn threads at shaft end? Could the original nut be split and halves drilled & tapped for push / pull bolts?
....no !!! 😏
It wouldn't work Steve... a new nut AND shaft is the real answer here but if the wear isn't "too" bad the reduction in backlash from the new nut alone will often suffice.
Backlash is present even in new screw/nut combos... learning to deal with it is a part of the machinists training, e.g. if you turn the feedscrew inwards and overshoot your mark by say 20 thou on the dial.... you don't just back off the 20 thou..if backlash is say 8 thou you have in reality only backed out 12 thou... you need to back out say 50 thou & then come back in to hit your spot...🙄
It sounds tedious but in reality it becomes second nature to a machinist & we don't even have to think about it when working ... 😎👍☘
Adam,
Thanks for the video! You'll have the G & E back making accurate chips soon. I noticed you upgraded the Monarch with the official "Doubleboost" light! Thanks for the SNS as well!
Have a good one!
Dave
Nothing wrong with trying to reach perfection...unless it becomes an obsession. Nice project.
Looks like it's time to make a new screw! I can watch these videos all day long and I'm not even a machinists.
Nice to highlight what didnt work out so well Adam, always learning and relearning what weve forgotten. Can really see a marked difference in the finish of the threads in the second nut. Cam imagine its always some sort of compromise on a used screw, no point in having the 'perfect' nut that wont go on or bind further up the thread. Reckon that .003" will work out great on the shaper, dunno what mine is but im sure its north of .030" lol.
I havent done it yet but remember reading somewhere an account of a goto guy for turned to fit threads. iirc he ran the compound inline with the spindle and rough plunge cut first, then finished with an undersized tool. When he was to depth hed then take the final cuts to fit using the compound to advance the cutter, ie just cutting one face of the thread to sneak up on the final fit. Ill give it a go when I get a mo.
Cheers
lol, you been there already. th-cam.com/video/P9-fH3fS724/w-d-xo.html
Ive been thinking about using square form threads also, the one in my compound is square form.
To start off, I'm no machinist but, if you make a new screw... Oh, there it is, the wear on the screw. :o) Nice job Adam!
The Road Runner will like your Acme Nuts! 😎
Good work. Sounds like there's a slight chatter when making those cuts. Is that due to the grain structure of the material or because the cutter has to be so far out from the tool post?
Long boring bars will do that with the high cutting area encountered in acme threads... taking a number of "spring-passes" without adding feed will usually clean up the chatter marks... also helping to sneak up on the fit... as Adam did in this vid.. 😎👍☘
Looking Good! But the time you finish working all the kinks out of that shaper it's going to be better than new. I was thinking (I know, no good can come of that) could you have made a spring loaded anti backlash nut. Would it have been worth the effort?
Learning to live with backlash is part of our training as machinists... & by that I don't mean ignoring it, but COMPENSATING for it in the operation of our machinetools...even NEW screw/nut combos will have a certain amount of backlash.
😎👍☘
This is where a shop notebook has value, you can go back and look at the last time you did the job and refresh on the "right way" to do it
Adam I guess you need to build a new screw and nut for what you are looking. And it will be really interesting to watch and a great video for channel. Great video adam.your monarch carriage is really smooth . Im strictly telling you we need some abom size machining content it has been so long since you show us something on that pacemaker. Thank you for a great video
You are the best machinist on you tube...Hands down...
It's a good thing, to make mistakes once in a while. it will make you smarter along the way. If one never makes mistakes, it's always because one is lazy and make nothing. everything mankind have, is because smart people made a lot of mistakes and learned from them. Thanks for a great tube. :-)
I call my mistakes experience!
So, Adam..... will your next video be making a new lead screw, so the .001 backlash is full-length? ;)
MN Sidewinder, he will need a brand new lathe where the lead screw and bed are not worn-out.
I can see you making a new screw Adam man? you know it has to be right, your the man Adam machine work is your game the thread is good at the end where there is no ware on the screw, so the answer is make a new one, as Keith Fenner says get it dun.
on your paperweight nut, couldn't you just take the bad side and face it down a bit in the lathe to make it look better or is there an overall length that you need to keep?
Great work Adam. I have to do an acme nut soon for my (small Southbend type) lathe, and its great to see something done so well. I have 35 thou backlash!!
Ive got you beat there, .050" plus on my old DSG cross slide atm lol.
Yes but mines only a 9" Smart and Brown Sabel. Your DSG is much bigger!!
You've got some grand old machines in that shop Sir.
Just the slights bit of chatter on the first thread. I have one of those bars, and it gives me the same signature! That second one does look better. Thanks for shooting that head on of the tool. Very informative.
Its due the flexing in the bar ,you can see it clearly on his last video.
Yup, I have that same style and size bar. When I was cutting the 2.125 x 5 threads on my face plate, it did that exact pattern. They are a bit thin and whippy, so lots of spring passes.... I didn't expect to see them on his though. I mean, he's a REAL machinist.... I don't even play one of TV!!!!
It doesnt matter,even best threading bars will flex under certain conditions-some more some less but they all do.Alot of focrce is applied when cutting profile threads.When you do normal boring with boring bar it tends to push bar down,When you cut threads all the force is applied to the left(or if you put threading bar upside down and thread in reverse like some people it will push it to right and push bar to the left) will tend to push threading bar to your right.
Will there be chatter depends on thickness of the threading bar which is determined by the hole you are threading -aka will it fit inside hole.Also the depth of cut and the pitch -higher pitch produces higher chatter so you need to lower your depth of cut and do more passes and lower your rpms.Material that you are cutting is one of factors -in bronze which is soft is easier to cut profile threads than in steel since it is softer.
First passes can be done on higher speeds and depths then you reduce it as knife goes in and cuts with more surface.
Geometry of knife-relief and rake angle have a lot to do whether there will be chatter or not.generaly you want negative angles for ease of cutting.
it sounds complicated but with experience you get to know which speed ,knife geometry and depth work best for type of job you are doing.Google helps also.
Put that thing together and lets see it work. I'm enjoying this series.
real nice close-up shots Thanks for shairing
Perfect timing I'm getting ready to try making some new lead nuts for my little old clapped out Bench Master milling machine and I'm by no means any more than a amateur hobby machinist but I have spent enough time around people with more experience that I'm more than up for giving it a go. The original nuts were brass was thinking about making them out of ductle any thoughts on the better choice for material?
I have been looking for an ACME thread on the Lathe that answers that. Great work
Adam, somebody's comment just got me to thinking. Since the tool head is going to be vertical the vast majority of the time, and so gravity is pulling down on the entire assembly as well, could you possibly grind your shaper tool bits such that your leading edge is not perfectly square with the tool holder, but instead has a bit of a rake, top of leading edge towards the ram, and not much of a rake at all, like 1-2 degrees?
What this is trying to do is that now the very bottom of the leading edge makes contact first and the cutting now progresses up the leading edge and results in the work-piece exerting a slight tug on the bit as its cutting, just like on a dovetail/spring bit theoretically, so now the cutting working with the tool-head weight in keeping backlash minimized instead of against it. I would be interested in hearing your thoughts on this in more detailed discussion on shaper toolbit grinding.
Adam, it seems like your problem now is that you need to make a new screw. You made a form tool according to your gauge shape but the shape of the thread on the screw obviously deviates from the correct shape. You can never achieve your target backlash with a worn screw. Also, if you are having a hard time with that last thread because the tool isn't fully buried in the material, why not make the nut an extra thread longer and then face it off later?
What i the reason for not making a new and precise acme rod? it looks like the sort of thing you could do in your shop.
I think that he would need a follow rest for the cross slide to limit the deflection. Cutting Acme thread creates quite a bit of tool pressure. That rod is hardened so he would probably need to heat treat the rod and then hard turn it to finish. That's a lot of work.
Ah okay i didnt realise that :)
Adam
Just a thought, but maybe machine the nut tight, then using valve grinding compound lap the nut to the screw to get the best fit and least backlash??
John
Good job, well done!
Don't you hate it when you get a "workable" part, but you know you can do better! Good video.
Did you try it spring pass after it almost fit?
Is it possible to use one of the old nuts with some diamond grinding paste to polish out the tight sections of the thread? Either that or chase a short section multiple times, adjusting the 4 jaw repeatedly to make the section concentric as you extract it?