Now that the lathe has a DRO, why not give the electronic lead screw a "stop at position" function? There's a good chance your DRO has some kind of serial communication that could be used to get position data.
I got the silly visual of mounting the chuck to a tire rim and going down to the tire shop to use the wheel balancer. (too much coffee I guess) He'll probably spin it between centers, and yes it will be fun to watch him do it.
Old engineers' expression ... "If you can't guarantee 100% accuracy &/or precision 100% of the time ... Make it adjustable! 🤔😁 Definitely applies to electronics too (my primary field). NICE unit! Great video as always!
While I’m loving you more and more my wife is headed the other direction 🤣 So many great projects to come on my G0602! Thanks again for great content and instructions
My lathe also has a screw-on chuck with 1 3/4 - 8 thread. The chucks that came with the lathe have a locking tab, that I see your spindle has provision for. To make a long story short, I operated my lathe without the locking tabs (as you're doing in this video). When I shut off the lathe, the drivetrain stopped well before the chuck as it unscrewed itself from the spindle, crashed onto the ways, then the floor, and then through a wall. My machine is standard AC drive. I think the 'ramp' function on your variable speed is the only thing that's saving you.
If your chuck unscrewed, something went wrong. There are many people with older lathes and they all say that a screwed spindle nose will hold on, even if you cut while running in reverse. My lathe, for example, I only ever tried 1-2mm cuts in steel in reverse because I'm scared, but it hold on just fine.
@@an2thea514 If you're cutting in reverse with a threaded chuck and no locks, please make sure you keep a camera running. We all want to see it when your luck runs out.
@@Clough42 I don't need to, you can literally try it yourself. I have access to one last threaded Lathe at work, my threaded Lathe and my Wood Lathes. As for Wood Lathes, I don't cut in reverse because I don't have reverse, but I have a Brake that I use pretty agressively and nothing happened yet. (For note, my boss brakes from 6000 to about 30 RPS on our Wood Shaper which I don't do and the Spindle doesn't unthread either but that's a different type of machine, so make of that what you will). My own lathe, well, since it has plain bearings I don't turn over ~300 RPM, but that's whatever. Biggest I do in reverse is cut tapers. 1-1.5mm DoC while fed with hand. Spindle is 2 1/4x5. As for the work lathe, my senior, the boss' dad has been in this shop since 1962 and that lathe is there since 1968. He is honest, makes sure every chuck is on tight and in his words, there have been no accidents because if that. And you know how much company lathes get abused. When we change chucks, the prybar is longer than me. Spindle is M105x7(or 6, whatever Voest used) Quinn likes to talk about how the old masters were so smart and such, but don't you think, if old manuals told you the chuck doesn't come off, if older lathe users in the forum say the chuck doesn't come off, that the chuck maybe really doesn't come off.
Using a vacuum cleaner can catch those cast iron chips. You might consider making an attachment to use a vacuum to pull chips through the spindle to prevent build up when boring or creating inside threads.
Came to say the same thing. If you have a spare Noga style arm and magbase (The knock-offs are perfectly good for this) you can mount a vacuum nozzle either to catch from the front or, as Tired old mechanic said, at the back and drawing through the spindle bore - the VacuuLathe :D
The thing for cast-iron is a shop vacuum. I mount the nozzle near the tool for facing and external and mount it at the left end of the spindle for internal cuts so it sucks through the chuck and spindle.
I thought about pulling through the spindle with a vacuum, but opted not to, just because I didn't want to draw all that junk though, where it will stick in the oil and be there forever. It was a lot easier to just let it fall and then vacuum it up, and wipe everything down as soon as I was done.
Oh no. Looks like I'm gonna have to add another chuck to my collection. I also purchased the 5c collet chuck for my PM1127 after watching your video and seeing how well it performed for such an affordable price.
Great video. I found that it's important to use the same screw to tighten with every time. My Toolmex 6 jaw has a 0 mark on one of the chuck screws, so it's easy to make sure you use the same screw every time.
Nice video, I always enjoy yours. I just got the 8" 6 jaw set true and the D1-4 backing plate. Checking and then removing a 1 inch precision ground dowl repeated exactly with a .0001 indicator. It is not a Bison for sure but it is way less money than I paid for my Bision 6 jaw.
I’ve said it before James, if you came to my shop, you’d think you were at home…on that note, I have had that chuck in my cart at Shars for probably a year. I WANT it, just can’t think of a solid reason why I NEED it over my 4 jaw, 6” Shars chuck. Nice job as always!
Hey since you have the electronic lead screw you should add a feature that will let you jog the carriage to help realign and chase already existing threads
An old time toolmaker here. STOP using copper/brass in your chuck/vice jaws. Use aluminum -- it's got a built-in coating of ALU Oxide, for greater grip . (Burn off the coatings, from pop cans)😎👍
The expensive precision highly trusted dial indicator says its only running out by half a though so Ill wind it up to 2500 RPM & check it with my mk1 eyeball - yep, that looks ok. CLASIC James. Balancing it will be fun. 1 go fully assembled or 3 steps - remove backing plate & balance it. Balance the chuck. Assemble & balance the combination? This will be interesting. Good luck & thanks.
Not sure I want to try taking material off the chuck itself. Taking it off the backing plate is easier, though it means it'll be a static balance and not a dynamic one. Worth a try to see what we get, though.
This is a little off topic but I noticed that you use a 2L coke bottle for coolant on you CNC mill. I don’t drink coke, I prefer cranberry juice, so I am using a cranberry juice container for my coolant reservoir. It’s a great idea!
Thanks for the well filmed and edited interesting video. I did the similar work adapting a 5# 3 jaw onto a 4# mini lathe. The adapter plate came from LMS and fit perfectly to both the chuck and the head stock, without any cuts! Using Randys knocker when tightening the bolts a run out of 1 thou was achieved. Not bad at all. However, the plate moves all the work some 1" away from the head stock and chatter happens more easily.
Very cool. I was a little worried about stickout, but because of the way the back plate is constructed, it ends up being exactly the same length as the stock 4-jaw.
Ha! And I just bought a Bison Set-Tru 5C collet chuck. Thinking about getting their 6 jaw. I didn't want to wait for Precision Mathews to restock their Set-tru's.
AG60 inserts are partial profile, not full. Full profile inserts have a flat next to the tooth that skims the top of the thread. I don't know why manufacturers put the second point on the partial profile inserts; it's certainly annoying. On the other hand, I have full profile inserts for every thread I make routinely, so I don't really care all that much. 😁
Thanks! That was my misunderstanding, apparently. I do see some AG60 inserts advertised as "full profile" but they're on dubious sites, like Aliexpress. The ISCAR catalog indicates clearly that AG60 indicates partial profile. (edit: capitalized ISCAR)
I've been lusting after one of those 6 jaw chucks for years, but my tooling budget doesn't line up with the sticker price on that thing of beauty.....🤣🤣
When you have to remove your way guide cover you can use a shop paper towel (the blue ones in a box) that’s been wetted with way oil so it will stick to the ways and not get picked up by the speed of those jaws whipping by.
When I setup a new 6-jaw adjustable , I’ll get the body of it to run true first, then see what the factory runout is. You may need to machine the jaws first with ceramic or cbn. Also, if it’s overseas equip. Good idea to disassemble and clean - check torques back plate. Cheers
Great video. I have the Shars 10” D1-6 3 jaw zero set Chuck. Very happy with it. Repeatable to .0005 and often times to .0001 - .0002. Very good Chuck. Even got it on sale 20 % off.
Could the electronic lead screw be programmed to automatically stop at a certain location when threading? Maybe disengage the nut for safety, but have it stop just in case you miss the mark.
I had the same thought. It might be difficult to make an absolute stop since the lead screw engagement point is variable, but a relative stop should be possible. Maybe as simple as X turns after a button press that indicates “first contact”. Not super accurate yet still relieving the pucker factor!
@@andreyv3609 You would either need to reverse the lathe spindle or have control over the cross-slide to pull the tool out. Reversing the lathe spindle could possibly work well on some machines and you wouldn't need to make any changes to the electronic lead screw.
@@yngndrw. He has electronic screw. It is attached to a separate motor that can be programmed to work in the opposite direction relative to the spindle
What I did when doing a similar job was to simply remove the chuck from the lathe with the work piece still attached, flip it around and test the fit that way. I figured the repeatability of the chuck against the spindle nose was good enough for the girls I go with. And it was. Other than the giant mess of all that cast iron it went great. For my 'practice' I made an aluminum spindle nose protector that I use when I'm using the internal 5C collet. So it was practice AND useful.
This is always an option. However, the 4-jaw chuck, with the backing plate mounted in it is pretty heavy and unwieldy, and I was a little afraid I would knock the plate out of alignment in the process. Having a dummy spindle nose is going to be handy in the future. I should have made one long ago.
How do the screws holding the chuck to the backplate affect the adjustment? Do you have to loosen them to let the chuck float? If not, would a dab of moly under the heads (and also maybe between the chuck and backplate) make the adjustment less sticky?
Drill a pair of holes 1/2" diameter x 1" deep in the outer edge of the backing plate. If you have the chuck off and you still need to unthread the backing plate you'll thank yourself.
I used one about this size on Stan Zinkosky's Logan lathe and really enjoyed it. I think his doesn't have removable jaw caps, so it's a little more compact.
Would be very cool to see the balancing of the chuck. Hope you do end up doing it. Not sure how much it would improve the chuck in practice but still cool to see how it would be done.
I plan to try to implement a carriage stop feature in the ELS so that I can set a stop point and, as long as I don't disconnect the lead screw, it will not go past that point towards the chuck. It'll still keep track of the spindle, but won't let the lead screw turn past my stop point. When I then reverse the spindle, the ELS will activate the lead screw when I pass the stop point in reverse, and drag the carriage back (it could be optimised too, to save some revolutions, but that comes later). Since I live in the metric world but my lathe has an imperial lead screw and while threading I kinda have to keep the half nut engaged all the time anyway, so it wouldn't add any inconvenience for me. On the contrary, as my lathe is set up now, without a brake, I can't thread up to a shoulder or even into a reasonably sized gutter. The electronic stop would fix that. Still haven't mounted my ELS, time in the shop has been scarce, but I plan to at some point.
I just realized that I can't be the first one to think of that, checked the pull requests on the repo and, as I suspected, someone else already implemented that feature. Perfect!
I've seen this video of James pup-up several times in RU-vid and wandered what to buy for more accuracy: 6-Jaw Chuck or a 5c-collet. I've seen this whole video and couldn't find the answer other than the big smile at the beginning 🙂 Is it a one-or-the-other situation that the 6-Jaw Chuck is an easy replacement for the 5c-collet with almost the same accuracy?
Work, Looks good! Heh, when you were first describing the 6-jaw and said you tighten the single pinion I didn't really think much about it and just assumed you meant you only need to tighten one of them. Then, later in the video I did notice you kept rotating the chuck around a lot to tighten the pinion. When you said it having a single pinion was part of the design I went "Oh! There actually *is* only a single pinion!" lol
Yeah, I think this is to improve repeatability. There will always be a little clearance in the fit of the scroll, and this way, the pinion is always pushing it off-center in the same direction.
@@Clough42 A thing that was sort of tickling in my mind was that I thought you were specifically rotating the chuck all the way around so that you could specifically tighten the same pinion for repeatability. Having the single pinion and the 4 adjustment screws are surely intended for repeatability. :)
I am curious about the pros and cons of cold bluing vs. nickel plating for wear and rust resistance. I was thinking about backing plates and tool holders in particular. Of course, it goes without saying, but I will say it anyway, I love your content and the superb production quality of your videos.
stupid question.. Why do you have to disengage the half nut? Couldn't the electronic lead screw automatically stop the stepper/servo at the right point?
Potentially. Rewinding and resynchronizing for the next pass can be pretty complicated, depending on the situation and would also make the project more complicated, hence less accessible.
James, here's an experiment I've always wanted to do: test repeatability on all three scroll pinions. I've always thought that the inevitable tiny bit of runout on the scroll itself could shove the whole clamp system a few tenths one way or another, depending on which pinion you stick the chuck key into last...
@@Clough42 And you even said that! D'oh! What got me started on this was thinking about repeatability on 3-jaw chucks, actually. I always wondered if you could mark a part's position, remove it and re-chuck it, using the same pinion, and get better centering...
@@d00dEEE Most multi-pinion chucks have one that's marked with an O that's the "master" pinion, which was tightened last when the jaws were ground at the factory. Tighten that one last for best repeatability.
As always, Thanks James. Just an interesting FYI... Adam Booth (Abom79) did a review on a (larger) 6 jaw chuck a while back & he found the repeatability was more consistent when he tweaked all 3 of the scroll pinions with the chuck key when repositioning the workpiece.
If I have to machine a lot of CI, I use an inverted tool with the lathe in reverse (or with the tool on the back of the part running forwards) so any spray of powder at least goes downwards instead of into my teeth. For fine cuts I use a cheap polished carbide aluminium insert which seems to make less annoying chips in CI/SG, (also brass and bronze) instead of powder. OK, they wear out fast, and inverting the tool means a bit of messing about, but my teeth thank me every time.
I wonder if anyone's done an actual study on cast iron vs steel backplates. Given the spindle is usually high tensile steel, how much will the material difference affect finish on small bench lathes ?
How would running in reverse work with this spindle being threaded? I would be fearful that the chuck/ mounting plate/ work piece would come off the spindle, but I have very little experience with home machining.
@@r2db Lathes with camlock or taper nose and key chuck mounts are fine for use in reverse but those with threaded chuck mounts are generally not. James mentioned that he has a Cunning Plan to handle that problem. Sounds interesting. My old lathe has a D1-4 camlock so it's fine in reverse. Also means I can use a rear toolpost for parting off without inverting the parting tool. Threading in reverse is much less stressful but the gutter groove is mandatory for the thread start. Cutting towards the chuck means you can pull out from the cut and leave a tapered entry. Takes lots of skill and timing unless you have auto-retract. I'm rubbish at getting it timed right so I stick to the easy way, with a gutter and running in reverse. Also need to consider tool rake/relief angles when threading in reverse. All enormous fun though.
I know it's a bit late now but there was a missed opportunity there to make a spindle nose replica on a MT shaft. You could have used it as your plug gauge but then also used it to mount your lathe chuck in other machines or parts of machines such as your tailstock. I use mine quite a lot like this.
@@Clough42 You could make such an arbour, but I use mine stationary for workholding. Opens up new options for things you can't spin in the lathe. Less useful maybe if you have a mill as you do. (I don't).
I have always wanted a good 6 jaw scroll chuck as well. I have thrown too many parts out of the 3 jaw, and stopped using them for any heavier work or cuts as they just don't hold as well. I have never thrown one from a 4 jaw, and 6 would fix the problem that the 3 jaw has. I usually try to cut the threads running in reverse and upside-down You have to be right on engaging the dial, but there is no risk of crashing the machine.
22:47 did you retighten the bolt hole pattern bolts before testing for repeatability? Or are you to adjust the 4 adjust tru bolts while the front bolts are holding the chuck to the plate tightly
I’m not sure exactly how you set it. The way it’s done is to snug the mounting screws, but not too tightly. Then work on the four screws until you get it to where you’re satisfied. And then, tighten the mounting screws down tightly, to whatever torque the manufacturer says. Often, your adjustment will move a small amount, and you might want to back the mounting screws off slightly, and readjust. It’s iterative. If you’re lucky, you’ll get it the first time, but often, you need to touch it up once. What I’ve found is that a good quality chuck will hold the setting for about one third to three times the diameter of the pin you’ve set it with, to 0.0002” of your initial adjustment, which is good enough. You can get these chucks easily to 0.0003” with a little care and even to below that if you have a known accurate pin. I use a 1” x 4” high precision carbide pin. In my 8” Buck. The pin is ground to +- 0.00005”, so good enough to measure to +-0.0002”. When using the pin, make sure it’s long enough to extend down the entire depth of the contacting jaws.
My much cheaper chuck was badly out of balance. First I indicated in the O.D. of the chuck. That fixed the out-of-balance, but then I needed to do an internal skim cut on the jaws with an internal stone tool post grinder.
Just been thinking about how to balance this perfectly, so you already got the accurate spindle position, all you need to do is add an accelerometer input into your lead screw software and then you will know exactly where the imbalance is 🤔
9:50 surely you have 2 dial indicators that you could use at the same time, no? I'm no machinist, but it seems like a torque wrench at 23:56 would be ideal so that you get repeatable results. Not to mention, without knowing the error in the unknown bar you're using, that could account for the runout when moving the bar around.
I wonder if I could drill and tap adjustments screws in my non- adjustable 3 jaw chuck never really thought about it I'll look at it when the when this cold front moves thru -3 is to cold
I recently bought a very similar looking import 6jaw by zentra. Might be from the same factory? definitely take it apart and deburr everythjng and clean out the grinding dust if you have not done so by now ✌️mine was really filthy on the inside. I really love watching your videos and learn something every time.
What? You don't like cast dust in your nose, ears and throat. Great job, brother! It must be so satisfying to use your electronic lead screw in this way.
This is when the automatic threading start and stop funtion would be nice no worrys about stopping the threading The CLOUGH42 ELS would take care of that
