Thank you for taking the time to show us how you replaced the acne screw with a ball screw. I don't own a lathe (yet) but I am building my first mini manual mill machine. I purchased an XY slide table of decent size and weight and as expected the play in the acne screws is beyond tolerable. The 16mm ball screws came in a few weeks ago but I need to mill out some cast material, and cut the top and bottom of the nut as you did. The tips on centering the parts, machining the mechanism to pre-load the ball screw bearings, and the next video on digital control of the axis is inspiring and educational. I will at least record my journey with the acne screw swap, and perhaps be inspired to post it some day. Thanks again for your time and efforts, they are greatly appreciated!
Hello Mr. Foal. Thank you for taking the time to do this video, It is a real service to us especially the novice user. I just changed the nut on my cross slide last week. I was able to find a generic nut with the same thread and pitch but the screw was worn out in the middle where the cross slide is used most. It was very hard to screw the nut on at the beginning of the unused part of the thread and then of course the back lash was back! about 3/4 of a mil. I am a bit disappointed. Your install was enlightening to say the least. Of course I dont have a bearing at the end of the screw. I can buy a new screw, but I would have to cut mine past the gear on a straight part and reattach the new one with an internal thread and connecting stud I guess. Then a small TIG weld all the way around. My lathe is very similar to yours in capacity but much heavier and bigger. It is an Hernault Batignolles (French lathe) from 1948. it weight 1,8 tons. I am eagerly waiting for your upcoming videos on the install of the stepper motors on your lathe. 6061 is a poor choice for the bearing holder and other components on a cast iron machine. with the water from the cooling system it acts like a sacrifiical anode. Lastly, all the cutting that you demonstrated on the other video with CNC like conversion was used with aluminum. Did you test the motors under hard conditions with deep cuts on SS or hi carbon alloys to duplicate the power and performance of your lathe with its original mechanical turning and cutting abilities, finish etc.? Thank you for taking the time to answer.
Great info, your set up of how you held the parts in place was great, that information is useful for holding parts in a Bridgeport mill or a full blown CNC mill.
Very nicely done... I just acquired a 16"Southbend lathe with the taper attachment that is in need of a replacement lead screw as I write this.. Now that I've seen what you've done here, I'm definitely going to explore this option to resolve the backlash and slope in not only this lathe, but to my other Southbends.... Thank you for sharing your upgrade and inspiring me as well as other's I'm sure! Razor!
This video was especially interesting, I've been thinking of a ball and screw for one of my machines. Thank You very much. will be watching the other video. The way you found the center of the rear was very smart. Thank You
A daunting task facing many of us with ageing machinery, I think the larger the machine the more option available until you get to micro lathes that use a more regular triangular thread form. A very soothing accent to go along with it also!
There are Heaps of Micro ball screws available for tiny machines I have seen some 6mm diameter screws on 3D printers and automatic pharmaceutical pill packing machines, ask your local bearing supplier for a catalogue on them.
Thanks for this video ! It inspires me to go forward with a cross slide ballcrew. Crosslide BS is a much more involved project than topslide ballscrew conversion, that I completed without milling the channel or modifying the nut at all. This "corner cutting " approach results in a slightly shorter effective slide distance Also, the conversions yield an amazing increase in "feel" or touch sensitivity. I replaced the crank dial with a larger round disk, fitted with a simple clamping brake.
I made a handle for my cross slide that you might consider. I took aluminum rod and machined it down. Threads on one end and a rounded head at the other end to act as a stop. A sleeve is machined to hold a ball bearing at each end. The shaft is machined to ID of the bearings. The ends of the sleeve are machined to just fit over the bearing OD. Just go in far enough to hold the bearing but leave a lip so they don't slide around inside the sleeve. Slide sleeve over shaft then screw it into your knob in place of your bolt. Use thread lock. It is so smooth and spins like a roulette wheel. It was worth my time.
Hi Tony, a new subscriber from Mentor, Ohio USA, here, my lathe is in need of a leadscrew replacement soon, I like your video and will look into replacing my leadscrew with a ballscrew. Thanks. saved your video for reference when that day comes.
I just found your channel a couple weeks ago And just wanted to say that I enjoy your video's. I haven't looked at the other comments yet but I say that your deliberate mistake is that you installed a right hand screw instead of the standard left hand.
You got it. I just did not even think about it. LH versions have been harder to find but I ordered one only yesterday. I am glad that you like the channel, share with your friends.
Great job. You have much more guts than me, I'd be way too scared to mill into my lathe cross slide, or any other part of my lathe for that matter. Luckily my lathe is still relatively new, if perhaps a bit cheap, so backlash isn't a huge issue. More projects!
A problem which might occur is that ball screws easily back drive compared to acme screws. You might find that the cross slide may move when exposed to the tool pressure.
Nice work. I did similar on my Colchester Bantam as part of conversion to CNC. For those who choose to retain the handwheel, it's worth pointing out that the original leadscrews are usually left handed so the handle will need to be turned the opposite direction but that's a small price to pay! Similar result if you change the Y axis on your milling machine.
sorry to be so offtopic but does anybody know a tool to log back into an Instagram account? I was dumb forgot the account password. I would appreciate any assistance you can give me.
@Fletcher Braylen i really appreciate your reply. I got to the site thru google and im trying it out atm. Looks like it's gonna take quite some time so I will get back to you later with my results.
Roy, Several reasons really. 1. I almost never had a need for it. 2. It was easier not to. 3. See ua-cam.com/video/WyG4LOG8EfA/v-deo.html and ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
There is a solid reason manual lead screws use square threads. On a CNC machine, a ball screw can be used because the driving motor applies a constant torque to the lead screw and holds in in position when movement is not wanted. If you put a ball screw on a manual machine backlash is reduced, but tool pressure can cause the screw to move. You would have to constantly hold the handwheel to keep the screw from turning. Back lash is not a problem, you have a DRO for measurement. Backlash does need to be considered if you have a taper attachment, but I don't think your lathe has one.
Brilliant! Being a novice, I must ask: since the pitch of the original screw is different from the new ball screw, if you left the original "handle" in place, the readings on the dial would be inaccurate? I do not have a DRO.
I have done several cnc conversions and found that although the ball screw is hardened steel, it is possible to mill it with a new carbide cutter, but it will have to be thrown away afterwards as the edge will be very dull if not chipped. Incidentally I am renovating a Lorch lathe from about 1900 and its feed screws are both right handed! This makes it a bit confusing to use and there is a danger of winding into the work rather than away from it especially if it is needed to be moved urgently. The use of ball screws is not a bad idea if LH screws can be sourced. I just checked and they are cheaply available on AliExpress. John
I got a LH one from that source and I put it on the shelf. It just was not good enough for me. Instead I motorised the lathe, have you seen the later video about that?ua-cam.com/video/WyG4LOG8EfA/v-deo.html
@@MotoChassisByTonyFoale Just had a look at it. Very interesting ideas. works well. I have been playing with the Clough 42 els on one of my lathes and to be frank struggled with it. I have done full cnc conversions to mills and lathes before but so far this has defeated me. I shall follow yours with interest. John
Excellent job. Really. I enjoyed hearing you explain all your steps and why you were doing it. Your ability to align the bearing hole was amazing. I found your mistake. You made this modification on your lathe instead of mine. What do I win? Any thoughts to converting the long lead screw? The one that drives the sled right and left? Thanks for sharing. I’m now a subscriber. Paul
The 'mistake' I can see with Tony's ballscrew upgrade is the screw itself is a conventional right hand helix thread so the indexing wheel has to be turned counterclockwise to infeed the cross slide/cutting tool. The original Acme thread is a left hand helix hence it will infeed with clockwise rotation.
I have bought several ball screws but I can only find one order and I am not sure if it was for this project. Here is the link. www.amazon.es/dp/B08L7SQZP6/ref=pe_3310721_185740151_TE_item
Ball screws have the added benefit anti backlash nuts which would remove the backlash alltogether. My question though, would it not be easier to create an anti backlash nut as replacement rather than modifying the lathe saddle?
If his is a 1236py I have a manual I can copy and send you. I believe they are readily available online but if not message me and I will get it out to you.
Doesn't the lack/reduction of friction mean you now have to hold the cross slide wheel or lock down the gibs when you take a cut for the tool to not be forced out of the cut?
Think about an ACME style thread, the reason that it stays where you put it is friction. The bearings that hold the ball screw are preloaded and they give enough friction. In any case my ball screw is motor driven and the motor holds it.
Great fix, thanks for sharing. I've just done a cut-and-shut with my Harrison M300 crosslide trapezoidal leadscrew at 1/4 of the price of a whole new screw. The ballnut is probably the superior option. Nice work. Was the deliberate mistake the handidness ? Traditionaly these are left hand threads.
Yes, it was the wrong hand for manual use. If you look at the later videos you will see that I added a ball screw for the Z axis and motorised them both, so the handedness doesn;t matter. Since then I have put the cross slide on linear rails.
Hi great vid very intuitive I have a student I am thinking of converting and I think your mistake was total length of the ball nut was considerably longer than the lead nut and with you putting a bearing block at the back reducing travel
Excellent job I have seen this conversion done before; the only drawback is the lack of a manual vernier dial; however, you don't even need a DRO there are cheap linear digital scales available powered by batteries or one of those phone type chargers. I have one set up on the manual spindle feed on my mill it's easier than using the very accurate power feed just for drilling. there are also lots of different types of ball nuts available as well square, rectangular, double flanged as well as load bearing thrust and support bearings and housings, and these can actually be cheaper than having a new screw and nut made.
Hey Tony, First, I would find it strange to have a RH thread vs the standard LH thread for the cross slide. I guess you get used to it but just so used to clock-wise being in vs out. Never looked, I assume they make LH ball-screws but probably at a premium? Second, I suppose you do not use the power cross feed often? I noticed the gear on the standard axis shaft. I supposed I don't use power cross feed all that often. Or you could convert to electronic if really wanted I suppose.
Yep, you got it. My "deliberate" mistake was ordering the screw without thinking about direction. There must be LH versions around but I have found none at the budget level since I realised my mistake. I am getting used to it but it does not feel natural. I have not crashed anything yet but I think carefully before moving it. I am so pleased with everything else about the changeover that I am prepared to work at getting used to the direction, although I shall continue searching for a LH version.
@@MotoChassisByTonyFoale I wouldn't have caught that as I jumped ahead to see the end and total new backlash . I am curious to know how well a new carefully machined nut would have worked , cost and taken to make ?
@@eflanagan1921 A machined nut is always going to have some backlash unless you make it a tight fit, but then it will wear much faster than a ball screw.
@@MotoChassisByTonyFoale Hi Tony, I spotted you'd got the wrong hand thread when I first saw the ball screw. Many people have been caught out between fixed and moving nut setups. Left handed ball screws are quite rare; since they're associated with CNC the reversal is just solved in software. You could kill two birds with one stone and fit a stepper, hybrid stepper, or servo to the screw. For manual use drive it with an MPG (manual pulse generator) and a variable frequency generator for power feed.
@@EVguru I have found it hard to source a LH version but a stepper and MPG were are the cards before I did this. Once you have that then why not add some smarts and have constant cutting velocity when facing? Heck, you only need minimal brains for that and an Arduino or ESP32 would handle it easily.
Hi Tony, Great video. I spent many years repairing many different types of machinery. Sometimes you have to think outside the box. Can you please tell me what the make and model is of this lathe?
Yes it could be made adjustable quite easily. The problem with adjustability is that it gives the opportunity to be adjusted badly. You might be interested in the electricfication of the screws in a new series at ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html The next video there will be looking at fitting the Z axis ball screw with a different solution to the end bearing. Thanks for your comment
Could have milled two slots in the back block in line where the bolts are, then place a jack screw under it; indicate the ball screw and lock it into place. Less set up and allowance for adjustment if the cross slide ways ever get wear in it.
Spot the mistake?...The ballscrew you ordered is right hand helix whereas the original Acme is left hand helix. Now you have to rotate the index/hand wheel counterclockwise to infeed the cutting tool.
Thank you for a very informative video, I have been considering doing this to my 1964 Colchester student and you have convinced me to do it, do you have a link to the parts please, regards Nigel Cox.
You can find the BOM for the electronic lathe conversion here; www.dropbox.com/scl/fi/u2vrih5s31ip3ku1qlwy8/BOM.xls?rlkey=g47lxsczuiqzmna0dx8nrb9pa&dl=0 This does not include the linear rail conversion but the only extras are the rails themselves and nuts and bolts.
given the cost of these balls screw I think its worth it. Im going to do the same for my Z axis and get rid of the half nut and use an electronic leadscrew.
How much travel did you lose? Couldn't see from the video, but if you had room, perhaps the cast iron collar would have been better placed on the opposite side of the bearing carrier? Nice work nonetheless.
Very good video. We have 12 small lathe in the labs and I think to do it to each of them. But we also have 3/5 axis mill and CNC lathe do help doing it...
Nice conversion video, thanks. The balls and leadscrew almost have the same hardness unlike the original lathe cross feed brass nut setup. Will the ballscrew get backlash in time and how then to reduce the play?
are you tony foale frame chassis manufacture from 70s if so this is steve mainwaring rode one you tz350 chassis owner cigy poole found your video interesting I have gone from manual to CNC haase mill lathe got excel d40 cnc be not needed but be interesting in doing conversion like you done were did you acquire electronics if you don't mind kind regards steve mainwaring
I have to plead guilty to your first question. Here is a one min video which you might find interesting. ua-cam.com/users/shorts7NpMMKi6BLE Send me an email and I'll send you some details of the conversion. I do the electronics and programming.
Great video thanks. I want to convert to a ballscrew on my milling machine but it will require me to do some turning on the ends of the ballscrew. Do you know if whatever they are made of they could they be turned?
do you think a 12x4 ball screw supported with angular contact bearings on both ends will be enough for a 14x40 lathe? thinking of putting the screw under slight tension so its never pushing the cross slide, but rather always pulling on either end bearings. ill have to make some kind of inverting gear system so that my hand wheel still work right. will see.
Wonderful project, I see further development will include graduations on the collar, I am interested in knowing the difference in pitch obtained by this modification. Enjoyed, cheers!
Thanks for the video. I am considering applying this to my 5913 Clausing that has a worn lead screw, My question is do you still have power feed on the cross slide ? BTW I am a new subscriber. I am impressed by your work.
You'll have power feed if you remove the gear from the original lead screw and mount it in the correct location on the ball screw. I am currently at the beginning stage of this same upgrade. On my lathe, KBC12X24, the gear for the power feed is held onto the lead screw with a roll pin, easy.
No I did not retain the cross slide power feed. It does not matter now because both axis are motorised, see a later video about the electronic conversion.
Great video on fitting the new ball screw and nut. I would like to change my acme cross slide screw and nut as well but the pitch is .125” or 8 TPI LH. There are lots of metric size suppliers but does anyone know who sells an 8 TPI ball screw and nut?
I had to stop and think before doing any movement. Since I went to electronic control it doesn't matter anymore because direction is only a matter of a software setting. See ua-cam.com/video/WyG4LOG8EfA/v-deo.html if you haven't already.
nice modification. however .03 backlash on a lathe cross slide means nothing as the cutter is always pushing back on the cutter. but i do understand why you did what you did.
Firstly it originally had 0.75 mm not 0.03 backlash. All I can tell you is that it made the lathe so much nicer to use and easier to control accuracy. If you watch the later videos you will see that I motorised the slides and minimal backlash is desirable for that. The recent videos show why it is even more important for me to have near zero backlash.
@@MotoChassisByTonyFoale .03 inch is nearly same as .75mm. I said i understand why you did it. i was just making a point that backlash on a crosslide is a moot point. I have worked on many lathes with .03inch backlash and made perfect parts.
what holds me from ball screw install on my cross slide is not finding a left-hand screw. i dont have a dro so that means 1 the dial will be inverted and worst of all my hand will also have to learn the wrong way........that may cause a crash or two.
I have heard that ball screws feel completely different than an Acme screw. The few people I have spoken to have explained that you don't have as much feedback. Eleven months on, what is your opinion?
I'm surpriced that you are even able to use the lathe manually. Typically ballscrews are used only in CNC machines because they need holding torque from motor. Normal threads should lock on a place by friction so no cutting force should turn the screw into different position. Ballscrews on the other hand, quite easily turn applied force into rotating motion making it impossible to make straight pieces unless you can mechanically lock the screw in place. Maybe there was enough friction in your system but others planning to do the same should take this into concideration
i always hear this but i had at work a manual mill from the 90s that had all axis with ball screws. So i don't understand. Never had any issue with the slides moving on their own.
@@fuckingpippaman Maybe you have worked with machines which are made for ballscrews, but if you change ballscrew into typical machine, like it's done when doing cnc conversion, those screws don't hold anything.
@@teropiispala2576 yeah i get it. But whats the difference? it didn't have any brakes on the handles / lead screws. It was just a classic manual mill with ball screws. And it didin't budge a thou. You could mill, drill, anything without engaging any way locks.
Great upgrade there. I always thought the original bronze nuts were 2 piece so you could adjust one of them fore / aft to slightly bind to remove backlash. Was the deliberate mistake not cutting the dovetail into the rear bearing block?
There are anti-backlash nuts as you mention used in various applications. I have never seen one on a lathe but that might be because I have not seen enough. I did cut the dovetail into the bearing.
Yes, that is true. The pitch has changed from 1/8" (3 mm) to 5 mm. I bought a LH screw to change the direction back to normal but the quality was bad and I did not fit it. I have cured the problem by fitting a motor. You will like ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
Yes that was a mistake. Since I went to electronic controller it doesn't matter anymore because direction is only a matter of a software setting. See ua-cam.com/video/WyG4LOG8EfA/v-deo.html if you haven't already.
Thank you for taking the time to show us how you replaced the acne screw with a ball screw. I don't own a lathe (yet) but I am building my first mini manual mill machine. I purchased an XY slide table of decent size and weight and as expected the play in the acne screws is beyond tolerable. The 16mm ball screws came in a few weeks ago but I need to mill out some cast material, and cut the top and bottom of the nut as you did. The tips on centering the parts, machining the mechanism to pre-load the ball screw bearings, and the next video on digital control of the axis is inspiring and educational. I will at least record my journey with the acne screw swap, and perhaps be inspired to post it some day. Thanks again for your time and efforts, they are greatly appreciated!
Nice job, reason for watching is I'm going to have to do the same, my lathe is over 100 years old so backlash is significant, cheers have subscribed
Terry,
You might like the latest here.
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
Hello Mr. Foal. Thank you for taking the time to do this video, It is a real service to us especially the novice user. I just changed the nut on my cross slide last week. I was able to find a generic nut with the same thread and pitch but the screw was worn out in the middle where the cross slide is used most. It was very hard to screw the nut on at the beginning of the unused part of the thread and then of course the back lash was back! about 3/4 of a mil. I am a bit disappointed. Your install was enlightening to say the least. Of course I dont have a bearing at the end of the screw. I can buy a new screw, but I would have to cut mine past the gear on a straight part and reattach the new one with an internal thread and connecting stud I guess. Then a small TIG weld all the way around. My lathe is very similar to yours in capacity but much heavier and bigger. It is an Hernault Batignolles (French lathe) from 1948. it weight 1,8 tons. I am eagerly waiting for your upcoming videos on the install of the stepper motors on your lathe. 6061 is a poor choice for the bearing holder and other components on a cast iron machine. with the water from the cooling system it acts like a sacrifiical anode. Lastly, all the cutting that you demonstrated on the other video with CNC like conversion was used with aluminum. Did you test the motors under hard conditions with deep cuts on SS or hi carbon alloys to duplicate the power and performance of your lathe with its original mechanical turning and cutting abilities, finish etc.? Thank you for taking the time to answer.
Brilliant tutorial. Thank you for making this educational video. I feel I could almost do this for my newly acquired lathe.
You might like the follow on videos here is the full list. ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
Great info, your set up of how you held the parts in place was great, that information is useful for holding parts in a Bridgeport mill or a full blown CNC mill.
Very nicely done...
I just acquired a 16"Southbend lathe with the taper attachment that is in need of a replacement lead screw as I write this..
Now that I've seen what you've done here, I'm definitely going to explore this option to resolve the backlash and slope in not only this lathe, but to my other Southbends....
Thank you for sharing your upgrade and inspiring me as well as other's I'm sure!
Razor!
Did you ruin your machine yet?
@@IamDaytrader
🤣🤣🤣🤣🤣🤣 No!
This video was especially interesting, I've been thinking of a ball and screw for one of my machines. Thank You very much. will be watching the other video. The way you found the center of the rear was very smart. Thank You
Glad that you found it interesting. Here is a playlist with all my lathe modifications
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
Thank You ,Sir,I will be watching them all.Charley@@MotoChassisByTonyFoale
A daunting task facing many of us with ageing machinery, I think the larger the machine the more option available until you get to micro lathes that use a more regular triangular thread form. A very soothing accent to go along with it also!
There are Heaps of Micro ball screws available for tiny machines I have seen some 6mm diameter screws on 3D printers and automatic pharmaceutical pill packing machines, ask your local bearing supplier for a catalogue on them.
Thanks for this video ! It inspires me to go forward with a cross slide ballcrew. Crosslide BS is a much more involved project than topslide ballscrew conversion, that I completed without milling the channel or modifying the nut at all. This "corner cutting " approach results in a slightly shorter effective slide distance Also, the conversions yield an amazing increase in "feel" or touch sensitivity. I replaced the crank dial with a larger round disk, fitted with a simple clamping brake.
Have you seen the later video showing the carriage ball screw conversion with motor drive?
I made a handle for my cross slide that you might consider. I took aluminum rod and machined it down. Threads on one end and a rounded head at the other end to act as a stop. A sleeve is machined to hold a ball bearing at each end. The shaft is machined to ID of the bearings. The ends of the sleeve are machined to just fit over the bearing OD. Just go in far enough to hold the bearing but leave a lip so they don't slide around inside the sleeve. Slide sleeve over shaft then screw it into your knob in place of your bolt. Use thread lock. It is so smooth and spins like a roulette wheel. It was worth my time.
Genius, this video answered a question I've pondered on for years.
New subscriber for sure..
Welcome aboard!
Hi Tony, a new subscriber from Mentor, Ohio USA, here, my lathe is in need of a leadscrew replacement soon, I like your video and will look into replacing my leadscrew with a ballscrew. Thanks. saved your video for reference when that day comes.
David,
You might like the latest here.
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
@@MotoChassisByTonyFoale Thanks Tony,
I just found your channel a couple weeks ago And just wanted to say that I enjoy your video's. I haven't looked at the other comments yet but I say that your deliberate mistake is that you installed a right hand screw instead of the standard left hand.
You got it. I just did not even think about it. LH versions have been harder to find but I ordered one only yesterday. I am glad that you like the channel, share with your friends.
Great job. You have much more guts than me, I'd be way too scared to mill into my lathe cross slide, or any other part of my lathe for that matter. Luckily my lathe is still relatively new, if perhaps a bit cheap, so backlash isn't a huge issue. More projects!
A problem which might occur is that ball screws easily back drive compared to acme screws. You might find that the cross slide may move when exposed to the tool pressure.
Just a question of adding a little friction. See the later videos which shows it motor driven. In my experience that problem is grossly exaggerated.
That was my first thought when i saw this. Wondering the real life experience in this subject.
It might be caused by unbalanced handle, chatter, vibration.
Thanks!
Great job mate !! Mine is a new lathe and I hate the backlash !
great modification - will get round to doing a similar mod to mine machine - thanks for posting
Nice work. I did similar on my Colchester Bantam as part of conversion to CNC. For those who choose to retain the handwheel, it's worth pointing out that the original leadscrews are usually left handed so the handle will need to be turned the opposite direction but that's a small price to pay! Similar result if you change the Y axis on your milling machine.
Mine is motorized now so it does not matter which hand the screw is. See the later videos for more info on that.
I was alerted to LH thread screws and I have one on order.
Very Nicely Done Only thing i Noticed was that now the direction of feed in is now opposite to original . Not a problem once you get used to it
You got it, but it doesn't matter now because it is motorised.
Just re-watched. Great video Tony and I look forward to more.
Have you seen this playlist
ua-cam.com/play/PLyn2snGjYlHwvzi0ztHJVwwFANxyTc2Kj.html
Reason to watch I m going to convert my conventional lathe in linear cnc production lathe. Thx so much
Go for it!
Hello Tony,
A really interesting video and a great approach to giving an older machine a new lease of life...
Take care.
Paul,,
Many thanks!
sorry to be so offtopic but does anybody know a tool to log back into an Instagram account?
I was dumb forgot the account password. I would appreciate any assistance you can give me.
@Rocky Brennan Instablaster :)
@Fletcher Braylen i really appreciate your reply. I got to the site thru google and im trying it out atm.
Looks like it's gonna take quite some time so I will get back to you later with my results.
@Fletcher Braylen it did the trick and I finally got access to my account again. Im so happy!
Thank you so much you saved my ass :D
You needed to add the relief cuts for the cross slide v groves to get full movement of the cross slide rewards. Nice upgrade btw!!
Thank you very much for this. Very much appreciated.
You're very welcome!
Good video. May i ask why you didn't reattach the power cross feed?
Roy,
Several reasons really.
1. I almost never had a need for it.
2. It was easier not to.
3. See ua-cam.com/video/WyG4LOG8EfA/v-deo.html and
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
Thank you for that helpful video. I will now change my lathe in the same way,
Tommy,
You might like the latest here.
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
Good video my friend ,stay healthy!
This was a great video. Very fascinating project. Thanks so much.
There is a solid reason manual lead screws use square threads. On a CNC machine, a ball screw can be used because the driving motor applies a constant torque to the lead screw and holds in in position when movement is not wanted. If you put a ball screw on a manual machine backlash is reduced, but tool pressure can cause the screw to move. You would have to constantly hold the handwheel to keep the screw from turning. Back lash is not a problem, you have a DRO for measurement. Backlash does need to be considered if you have a taper attachment, but I don't think your lathe has one.
Really enjoyed watching that. Thanks for spending the time to share.
Glad you enjoyed it
Brilliant! Being a novice, I must ask: since the pitch of the original screw is different from the new ball screw, if you left the original "handle" in place, the readings on the dial would be inaccurate? I do not have a DRO.
If you left the same dial, yes. A 5 mm pitch ball screw will move the cross slide 5 mm per revolution and a 0.125" pitch screw will move 3.125 mm.
So enjoyable watching that, thanks Tony!
My pleasure
Very informative video. Thanks for all the details. Wish I had seen your channel long time ago. Defo a new subscriber from a fellow machinist... Greg
Thanks
Thanks for the video. Very informative. Just wondering whether you attached the power drive nut to the ball screw, and if so, how?
No I did not add the mechanical drive, but later I motorize it. See later videos for details.
Great mod but did I miss where you bought the new screw/bearing?
I have done several cnc conversions and found that although the ball screw is hardened steel, it is possible to mill it with a new carbide cutter, but it will have to be thrown away afterwards as the edge will be very dull if not chipped. Incidentally I am renovating a Lorch lathe from about 1900 and its feed screws are both right handed! This makes it a bit confusing to use and there is a danger of winding into the work rather than away from it especially if it is needed to be moved urgently. The use of ball screws is not a bad idea if LH screws can be sourced. I just checked and they are cheaply available on AliExpress.
John
I got a LH one from that source and I put it on the shelf. It just was not good enough for me. Instead I motorised the lathe, have you seen the later video about that?ua-cam.com/video/WyG4LOG8EfA/v-deo.html
@@MotoChassisByTonyFoale Just had a look at it. Very interesting ideas. works well. I have been playing with the Clough 42 els on one of my lathes and to be frank struggled with it. I have done full cnc conversions to mills and lathes before but so far this has defeated me. I shall follow yours with interest.
John
@10:20 yes. Don't put too many constraint if not needed. Work becomes more difficult without any benefit.😊😊😊
Excellent job. Really. I enjoyed hearing you explain all your steps and why you were doing it. Your ability to align the bearing hole was amazing.
I found your mistake. You made this modification on your lathe instead of mine. What do I win?
Any thoughts to converting the long lead screw? The one that drives the sled right and left?
Thanks for sharing. I’m now a subscriber.
Paul
The 'mistake' I can see with Tony's ballscrew upgrade is the screw itself is a conventional right hand helix thread so the indexing wheel has to be turned counterclockwise to infeed the cross slide/cutting tool. The original Acme thread is a left hand helix hence it will infeed with clockwise rotation.
Look for a later video for the lead screw change.
where did you get ball screw? thanks
I have bought several ball screws but I can only find one order and I am not sure if it was for this project. Here is the link.
www.amazon.es/dp/B08L7SQZP6/ref=pe_3310721_185740151_TE_item
yep, i noticed in the block you did not do the Dove grove so the assembly would hit the back bearing block and stop unless you fixed that.
There was no problem there.
Should have been left-hand thread?
You got it.
Ball screws have the added benefit anti backlash nuts which would remove the backlash alltogether. My question though, would it not be easier to create an anti backlash nut as replacement rather than modifying the lathe saddle?
Easier is easier. I wanted better.
I have the same lathe, any chance you have a manual for yours?
If his is a 1236py I have a manual I can copy and send you. I believe they are readily available online but if not message me and I will get it out to you.
No sorry I do not have a manual.
Doesn't the lack/reduction of friction mean you now have to hold the cross slide wheel or lock down the gibs when you take a cut for the tool to not be forced out of the cut?
With a ball screw how do you get the self-retention?
Think about an ACME style thread, the reason that it stays where you put it is friction. The bearings that hold the ball screw are preloaded and they give enough friction. In any case my ball screw is motor driven and the motor holds it.
Great fix, thanks for sharing. I've just done a cut-and-shut with my Harrison M300 crosslide trapezoidal leadscrew at 1/4 of the price of a whole new screw. The ballnut is probably the superior option. Nice work. Was the deliberate mistake the handidness ? Traditionaly these are left hand threads.
Yes, it was the wrong hand for manual use. If you look at the later videos you will see that I added a ball screw for the Z axis and motorised them both, so the handedness doesn;t matter. Since then I have put the cross slide on linear rails.
Very much enjoyed watching your video. Thanks for sharing, just subscribed.
Thanks for the sub!
How do you lock the cross slide to arrest any movement during a heavy cut?
I have enough rotary friction to take care of that.
Hi great vid very intuitive I have a student I am thinking of converting and I think your mistake was total length of the ball nut was considerably longer than the lead nut and with you putting a bearing block at the back reducing travel
Wrong. I got a RH screw without thinking about direction.
@@MotoChassisByTonyFoale me too. Screw it! I'll get use to it.
Excellent job I have seen this conversion done before; the only drawback is the lack of a manual vernier dial; however, you don't even need a DRO there are cheap linear digital scales available powered by batteries or one of those phone type chargers. I have one set up on the manual spindle feed on my mill it's easier than using the very accurate power feed just for drilling. there are also lots of different types of ball nuts available as well square, rectangular, double flanged as well as load bearing thrust and support bearings and housings, and these can actually be cheaper than having a new screw and nut made.
Hey Tony,
First, I would find it strange to have a RH thread vs the standard LH thread for the cross slide. I guess you get used to it but just so used to clock-wise being in vs out. Never looked, I assume they make LH ball-screws but probably at a premium?
Second, I suppose you do not use the power cross feed often? I noticed the gear on the standard axis shaft. I supposed I don't use power cross feed all that often. Or you could convert to electronic if really wanted I suppose.
Yep, you got it. My "deliberate" mistake was ordering the screw without thinking about direction. There must be LH versions around but I have found none at the budget level since I realised my mistake. I am getting used to it but it does not feel natural. I have not crashed anything yet but I think carefully before moving it. I am so pleased with everything else about the changeover that I am prepared to work at getting used to the direction, although I shall continue searching for a LH version.
@@MotoChassisByTonyFoale I wouldn't have caught that as I jumped ahead to see the end and total new backlash . I am curious to know how well a new carefully machined nut would have worked , cost and taken to make ?
@@eflanagan1921 A machined nut is always going to have some backlash unless you make it a tight fit, but then it will wear much faster than a ball screw.
@@MotoChassisByTonyFoale Hi Tony, I spotted you'd got the wrong hand thread when I first saw the ball screw. Many people have been caught out between fixed and moving nut setups. Left handed ball screws are quite rare; since they're associated with CNC the reversal is just solved in software.
You could kill two birds with one stone and fit a stepper, hybrid stepper, or servo to the screw. For manual use drive it with an MPG (manual pulse generator) and a variable frequency generator for power feed.
@@EVguru I have found it hard to source a LH version but a stepper and MPG were are the cards before I did this. Once you have that then why not add some smarts and have constant cutting velocity when facing? Heck, you only need minimal brains for that and an Arduino or ESP32 would handle it easily.
Changing the direction of the feed would have me unintentionally gouging parts like crazy. Hope you're able to find a LH version of the screw.
I did not gouge anything but I had to think carefully before moving. It is motorised now, see later video.
Hi Tony, Great video. I spent many years repairing many different types of machinery. Sometimes you have to think outside the box. Can you please tell me what the make and model is of this lathe?
It is a JET 12x40
The bearing receiver could be made to adjust in x and y so you could dial in the alignment, Yes?
Yes it could be made adjustable quite easily. The problem with adjustability is that it gives the opportunity to be adjusted badly. You might be interested in the electricfication of the screws in a new series at
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
The next video there will be looking at fitting the Z axis ball screw with a different solution to the end bearing.
Thanks for your comment
Could have milled two slots in the back block in line where the bolts are, then place a jack screw under it; indicate the ball screw and lock it into place. Less set up and allowance for adjustment if the cross slide ways ever get wear in it.
I think using a cylindrical ball nut would probably be better for this, but they are hard to get.
I did consider that and I do have one spare but in this case it was easier to fit the flange type. I use a cylindrical one on the Z axis of my mill.
Where you bought tha ball screw? My lathe uses a 2 mm pitch screw. Good diy video 👍🙂
Off Amazon or eBay I forget which one.
@@MotoChassisByTonyFoale have you part number for search? Thanks 🙂
@@Alan-Steve Search on "CNC Ballscrew 1605"
@@MotoChassisByTonyFoale thanks! 🙂
Im sure there are many comments about it. Left-handed shifted to right-handed thread. How does that feel?
The wrong way meant that I always had to think before turning the wrong hand screw. It does not matter now that it is motorized.
Spot the mistake?...The ballscrew you ordered is right hand helix whereas the original Acme is left hand helix. Now you have to rotate the index/hand wheel counterclockwise to infeed the cutting tool.
You got it, but you need to move on to the video about motorising it and adding a ball screw to the Z axis.
@@MotoChassisByTonyFoale Thanks for the reply,Tony. i will look at the other videos. I subscribed recently to your channel.
Thank you for a very informative video, I have been considering doing this to my 1964 Colchester student and you have convinced me to do it, do you have a link to the parts please, regards Nigel Cox.
You can find the BOM for the electronic lathe conversion here;
www.dropbox.com/scl/fi/u2vrih5s31ip3ku1qlwy8/BOM.xls?rlkey=g47lxsczuiqzmna0dx8nrb9pa&dl=0
This does not include the linear rail conversion but the only extras are the rails themselves and nuts and bolts.
Thank you very much this really will help.@@MotoChassisByTonyFoale
given the cost of these balls screw I think its worth it. Im going to do the same for my Z axis and get rid of the half nut and use an electronic leadscrew.
Good luck with it
Just wandering, did you want left hand drive??? That would throw me out of wack😵💫🤔
see the later video on adding a motor.
How much travel did you lose? Couldn't see from the video, but if you had room, perhaps the cast iron collar would have been better placed on the opposite side of the bearing carrier? Nice work nonetheless.
I lost hardly any travel. If I bored the collar, the wall thickness would have been too thin on the sides. Thanks for the idea though.
Very good video. We have 12 small lathe in the labs and I think to do it to each of them. But we also have 3/5 axis mill and CNC lathe do help doing it...
Nice conversion video, thanks.
The balls and leadscrew almost have the same hardness unlike the original lathe cross feed brass nut setup.
Will the ballscrew get backlash in time and how then to reduce the play?
After two years of regular use I have had no problems with wear but it gets a lot of oil. See my current videos to see the backlash measurements.
Nice video Tony, is the power crossfeed no longer in use?
No it is not, I hardly ever used it and I may put a motor on it.
Now I have power cross feed watch the latest here
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
Very interesting. Nice work
are you tony foale frame chassis manufacture from 70s if so this is steve mainwaring rode one you tz350 chassis owner cigy poole found your video interesting I have gone from manual to CNC haase mill lathe got excel d40 cnc be not needed but be interesting in doing conversion like you done were did you acquire electronics if you don't mind kind regards steve mainwaring
I have to plead guilty to your first question. Here is a one min video which you might find interesting. ua-cam.com/users/shorts7NpMMKi6BLE
Send me an email and I'll send you some details of the conversion. I do the electronics and programming.
Great video thanks. I want to convert to a ballscrew on my milling machine but it will require me to do some turning on the ends of the ballscrew. Do you know if whatever they are made of they could they be turned?
I had no problem turning the ends with carbide tipped tools.
@@MotoChassisByTonyFoale many thanks for that
do you think a 12x4 ball screw supported with angular contact bearings on both ends will be enough for a 14x40 lathe? thinking of putting the screw under slight tension so its never pushing the cross slide, but rather always pulling on either end bearings. ill have to make some kind of inverting gear system so that my hand wheel still work right. will see.
12 seems a bit small to me for that size lathe, but I have never tried it.
They make ballscrews left handed no need for inverting gear system mate
thay are hard to come by and when you finde them very expensive
Would like to do this conversion myself. Curious as to where you are getting your ball screws.
The RH version was off Amazon but I was alerted to LH versions here
www.aliexpress.com/item/1005001334343453.html
It looks like you eliminated the power cross feed gear ?
See the later videos which shows it motor driven.
how can you fix the thread screw? mine is trying to stay in while threading .
Roger,
This is one way, see the latest here.
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
You don't show how you mounted the bracket for the ball screw in the back. I would have drilled and tapped holes when you had
the saddle on it's side.
I drilled holes in the bearing block and then spotted through. the block was spiggoted to the cross slide for alignment.
If you use an externally threaded ball nut you will have more clearance. Just make a threaded bracket in place of acme nut.
I use one of those on the Z axis of my mill but it wasn't so easy to fit on the lathe.
@@MotoChassisByTonyFoale managed to squeeze one on an atlas th54
Wonderful project, I see further development will include graduations on the collar, I am interested in knowing the difference in pitch obtained by this modification. Enjoyed, cheers!
The pitch is discussed in the video.
I see no reason to add graduations, I always use a DRO.
Thanks for the video. I am considering applying this to my 5913 Clausing that has a worn lead screw, My question is do you still have power feed on the cross slide ? BTW I am a new subscriber. I am impressed by your work.
You'll have power feed if you remove the gear from the original lead screw and mount it in the correct location on the ball screw. I am currently at the beginning stage of this same upgrade. On my lathe, KBC12X24, the gear for the power feed is held onto the lead screw with a roll pin, easy.
No I did not retain the cross slide power feed. It does not matter now because both axis are motorised, see a later video about the electronic conversion.
What happened to the gear for the carriage
Sorry but I do not understand the question.
Great video on fitting the new ball screw and nut. I would like to change my acme cross slide screw and nut as well but the pitch is .125” or 8 TPI LH. There are lots of metric size suppliers but does anyone know who sells an 8 TPI ball screw and nut?
My acme screws were imperial but that was no problem, I just replaced with metric ball screws.
I wouldn’t mind changing to metric but I have no digital readout.
thanks for that i need to do mine that way.
Did you find it difficult to get used to direction change
I had to stop and think before doing any movement. Since I went to electronic control it doesn't matter anymore because direction is only a matter of a software setting. See ua-cam.com/video/WyG4LOG8EfA/v-deo.html if you haven't already.
nice modification. however .03 backlash on a lathe cross slide means nothing as the cutter is always pushing back on the cutter. but i do understand why you did what you did.
Firstly it originally had 0.75 mm not 0.03 backlash. All I can tell you is that it made the lathe so much nicer to use and easier to control accuracy. If you watch the later videos you will see that I motorised the slides and minimal backlash is desirable for that. The recent videos show why it is even more important for me to have near zero backlash.
@@MotoChassisByTonyFoale .03 inch is nearly same as .75mm. I said i understand why you did it. i was just making a point that backlash on a crosslide is a moot point. I have worked on many lathes with .03inch backlash and made perfect parts.
@@blitzkrueg07 You did not specify inches in your first post only .03
Nice work
Thanks
Thank you for sharing.good job
what holds me from ball screw install on my cross slide is not finding a left-hand screw. i dont have a dro so that means 1 the dial will be inverted and worst of all my hand will also have to learn the wrong way........that may cause a crash or two.
The wrong way meant that I always had to think before turning the wrong screw. It does not matter now that it is motorized.
left or right screw?
I got a RH screw but it should have been LH.
I have heard that ball screws feel completely different than an Acme screw. The few people I have spoken to have explained that you don't have as much feedback. Eleven months on, what is your opinion?
It has a much more precise feel to it.
so you have lost auto feed ?
Only for a short time. I added electronic control and motorized it. See the later videos on this.
I'm surpriced that you are even able to use the lathe manually. Typically ballscrews are used only in CNC machines because they need holding torque from motor.
Normal threads should lock on a place by friction so no cutting force should turn the screw into different position. Ballscrews on the other hand, quite easily turn applied force into rotating motion making it impossible to make straight pieces unless you can mechanically lock the screw in place.
Maybe there was enough friction in your system but others planning to do the same should take this into concideration
its always good practice to lock slides before the cut. thus eliminating this type of problem
@@chisdalton9652 Maybe in finish cut but otherwise that would be terribly inconvenient.
i always hear this but i had at work a manual mill from the 90s that had all axis with ball screws. So i don't understand. Never had any issue with the slides moving on their own.
@@fuckingpippaman Maybe you have worked with machines which are made for ballscrews, but if you change ballscrew into typical machine, like it's done when doing cnc conversion, those screws don't hold anything.
@@teropiispala2576 yeah i get it. But whats the difference? it didn't have any brakes on the handles / lead screws. It was just a classic manual mill with ball screws. And it didin't budge a thou. You could mill, drill, anything without engaging any way locks.
Great upgrade there. I always thought the original bronze nuts were 2 piece so you could adjust one of them fore / aft to slightly bind to remove backlash.
Was the deliberate mistake not cutting the dovetail into the rear bearing block?
There are anti-backlash nuts as you mention used in various applications. I have never seen one on a lathe but that might be because I have not seen enough.
I did cut the dovetail into the bearing.
Thanks
Samael,
You might like the latest here.
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
Great Vid - thanks Tony :)
Very welcome
Поменялось направление и шаг резьбы , надо менять лимб и заново привыкать крутить в другую сторону
Yes, that is true. The pitch has changed from 1/8" (3 mm) to 5 mm. I bought a LH screw to change the direction back to normal but the quality was bad and I did not fit it.
I have cured the problem by fitting a motor. You will like
ua-cam.com/play/PLyn2snGjYlHw_e4LomNphh8KleeqPiqpz.html
useful info nice job
Thanks
hello how about the camshaft design software
There are only 24 hours in a day.
@@MotoChassisByTonyFoale ok
@@MotoChassisByTonyFoale how the video
Should be a left hand thread. Deliberate mistake ? Enjoyed the video though. 😊
You got it, but it doesn't matter now because it is motorised.
Superb
A left hand screw is the only way to go. A right hand screw????
Yes that was a mistake. Since I went to electronic controller it doesn't matter anymore because direction is only a matter of a software setting. See ua-cam.com/video/WyG4LOG8EfA/v-deo.html if you haven't already.