Hardturning a precision bushing
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- เผยแพร่เมื่อ 23 พ.ย. 2024
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"it is what it is" when Stefan has error free circular part on his lathes chuck jaws for 2nd ops, and dial test indicators needle is frozen solid when hand turning chuck... Always glad to see genuine satisfaction when hit "nominal".
"Putting something in the hole is always ehh pretty good!" 23:20
After learning so much from watching videos by you and Robin, I machined a part on my hobby lathe to within 3 microns.
Resisting the urge jo jump for joy I stepped back and just said “not bad” in your honour. 😂
"Decent" is the ultimate accolade.
Kinda ok-ish lol
"close enough"
"acceptable" "within reason"
Beautiful work as always, and very instructive and interesting. I moved to Germany from the States in 1965 and began work on my doctoral thesis at the Max Planck Institute for Biological Cybernetics. When I saw the gorgeous workshop at the institute I asked if I could do an apprenticeship so that I knew what could be made and how it would be done. After 6 months of filing and hand sawing, etc. I moved on to the lathe and finally milling machine. It was a challenge for an American where "cheap and dirty" was what I had grown up with. I soon learned that "Perfekt ist gerade gut genug!" Almost 60 years later that mindset is permanent. I really appreciate your videos Stefan. Thank you very much.
Very nice work Stefan! Thanks for all the plugs :-) Love the indicating, on the first move < .002mm
ATB, Robin
From now on I shall be referring to my tweezers as my heavy-duty fingers.
came down here to say the same thing
Always something new to learn watching your wonderful presentations. In my former life working in histopathology, cutting and handling thin tissue ‘sections (slices) about 5 microns thick was all in a days work, as was hand sharpening microtome knives with a nick free edge was also a tedious skill to be acquired . In my spare time I built big optical telescopes for astrophotography, making the optical mirror surfaces to a tenth of an Angstrom took my manual skills to a whole new level. As you say, working to a thou or two is ‘blacksmithing!!. I appreciate your skills and desire to work to very fine tolerances. Thank you for sharing your skills. 👍😁🇦🇺
Thanks Stefan. You are an artist for for sure. Great story teller to in how you meet your goals. I have a Krupps bread slicer. The blade holder screw went missing. I designed a replacement using an internet picture and the dimensions of the machine. It works great and I printed it out in PLA. Not the strongest, but if it breaks, I print another. In any case, it looks a lot like this part that you made today. Felt a strong connection with you here. Your videos help keep me interested and motivated in learning more and more about 3D design and making precision stuff. You are the best! Or, since there can't be a best, one of the best around.
two things:
1. i'm glad you consider "perfect" to be "good enough"
B. i have to assume your customer is your twin brother.
An "error in the communication". Other wise known as an "üpkehfuckt" 😖
I always loved hard turning with CBN.
The company I worked for we had Hardinge HLVs for small work with full internal and External collets, step collets etc. We almost never ran a chuck on them. The thing I really loved about the Hardinge was the 5C taper was integral to the spindle.
Just finished it. This was exceptional, many thanks for sharing. I might never make it that far, but you bet I'll try! Thanks again
Stefan, you are an excellent instructor. Thank you for this latest lesson. Beautiful work.
Thank you Stefan. De burring/ chamfering with carbide ball is awsome! simple but brilliant!
kind regards from John Spargo in Cape Town
They turned out great I love the finish I get doing hard turning.
That chamfering technique was great! Thanks 😁
The finish from hard turning is always so satisfying. I love the precision work.
Thanks for showing the quill hand feed and other informative but rarely shown details! Good and patient mentor!
I was so impressed with your Mahr dial test indicator I got myself one that it accurate to 0.00005". Took a month to get here. Being a Brit I should have gotten myself a metric one like yours but I do live in ye ole US of A.
5:27 fantastic tip. I will add this to my collection of "ways to f up a part" collection in my head for when im making something. Thanks!
i found this one out long ago it even matters sometimes in 3d printing given the cheap as chips cap head screws 3d printing people tend to use
good way to show it though and seeing it measured really drives it home
Just to let you know, as a drafter if there are no dims referenced from a center line there is no reason to put one in. The center line was referenced on the right hand view to a dim and doing more would increase the cost of the print work because it's charged by number of steps required. There also isn't geometric tolerances in this part referenced from the center line so maybe these reasons were why the center line was not included in the left view.
Great video and terrific workmanship. Question: I have an Adjust-Tru chuck similar to yours, and it mounts to the backplate with screws from the face of the chuck, thus squeezing the all of the chuck elements together. If those screws are too tight, the set screws that adjust the runout will not budge. If those screws are too loose, the chuck will not stay registered on center under tool pressures. Finding the right balance of tightness of the mounting screws has proven to be elusive. How have you set up the chuck so that the set screws can actually function, but the chuck can’t be driven out of concentricity when machining? I’m assuming once the chuck is centered, you seat all the set screws to prevent the chuck from shifting? Or is there some magic mounting screw torque setting that you have discovered?
I don't have an adjustable chuck but I was wondering the same thing.
Truly outstanding. A 40.14 minute glimpse into another world. Danke.
14/60=0.23333....
Inspirational work! As usual.
Love the internal chamfer with just a battery drill and a rotary burr. At first I thought it was a Stefan joke amid all the micron accuracies, but it's quick, simple and quite adequate for the application. Thanks for posting.
Impressive lathe with a moving chuck and fixed tool post. Technology is moving on quickly. I remember the days of fixed chucks. Moving tool posts in my day.
Incredible! Keep producing videos like this where I get to learn and be awed at the same time and I will keep watching! 👍
Great job Stefan. I enjoy the care you take with all your projects.
Excelent job. No complains at all. I call it a day. Thank you for sharing.
I picked up the spherical burr trick from a watchmaking video, I ground flats on mine so I can use a tap wrench as a handle.
That solid indicator stand is way to go. Thanks to Robin ja Stefan about the inspiration.
I made a downgraded version (no fine adjustment) for myself and it has impacted my way of doing things ... to the better direction I hope.
Stefan, Your videos have always been too short for me ... maybe I should seek for help ...
Always a delight and an education to watch.
Thank you Stephan, that is beautiful workmanship!!
Looking forward to your next offering with great anticipation (as always).
Excellent as always.
Stay safe and make 99.9999 % of us
viewers smile.
Nice work Stefan and I like the detail to which you explain your actions.
Nice job Stefan as always! Were i work all of our lathes have sloppy fitting chucks, we use a copper hammer to make fine adjustments, pretty brutal but it works great.
Yeah, I've seen that too.. our old machines just got worse when the "machinists " started hammering on them. They hammered the locking handle on a quick change into two pieces one day.
Stefan, very nice machining. Thanks for a few tips I grabbed from you while viewing this. Oh and beautiful lathe, unbelievably tight as far as no run-out.
Great! My machining has improved no end thanks to Your videos. Dànken.
Gday Stefan, absolutely beautiful work, the inserts leave a mirror finish without any polishing, throughly enjoyed this video, thanks for sharing, take care, Matty
Wish I had 1/10th your skill. Very impressive. :)
As soon as I saw the 0.000 tolerances I knew immediately for who these are for! 😄
Nice work Stef 👌
not sure if this is common knowledge but u can usually get a lot of the gunk off a loaded up lapping film with a pencil eraser. doesn't get everything though and as u said a bit of oil works great too. erasers work on diamond laps too
I did not know that! Thanks.
liked, subscribed, commented.. Stefan, thank you for the content my soul craves :D. And please don't ever change your intro/outro music, I love it :D
Full music here: th-cam.com/video/ljOMXgfflRI/w-d-xo.html&ab_channel=TheWickedNorth what you are refering to is around the 1.30 time stamp.
@@Windgonner this isn't the piece. I've spent way too long looking, but I can't find it. Pretty sure it's Rachmaninoff though
@@georgehelliar I can only blame my hearing deficiency.
Stefan FYI ceramic inserts with a 1 radius work best for turning hard.
Thinking a bit more about using a round carbide bur rather than a countersink is its very much more accurate when doing by hand, with the ball end bur its always perfectly aligned(being round) even if its not, with a countersink even a couple of ° out you will see in the end result. Great tip.
The hardturning is incredible 👍👌🇦🇺
Whatever it is, someone must have a pretty healthy budget for it!
It was not free - But I did also not charge a ton. Its a friend and also a good skillbuilder project. And I got to film it.
So its a win-win.
@@StefanGotteswinter Ok right on; thank you for sharing the whole process!
Great video, as usual. I wish you had talked a little bit more about regrinding of the insert. Looked to me that you now created a negative rake. If that is so, is that better or a compromise? I love reconditioning and repurposing tools and machines so I am very interested in this aspect of you shop expertise. Thanks again.
My guess would be some thing like, hard parts will always destroy positive rake tooling, so at best you’ll begin with neutral rake. Hard part machining mechanism taken to extremes resembles grinding, abrading, more than conventional chip producing machining, so a degree or two more negative won’t likely affect things terribly.
Others have said that red hot chips are not requisite to hard machining, though that is seen often enough.
Additionally more negative rake/radiused edges result in stronger tools.
And possibly the cutting conditions may actually be more stable with definitively negative rake tooling compared to even a neutral rake edge.
@9:29 did you notice what happened to the dial when you reverse the rotation? I think that is from the bearings on that headstock, and perhaps you should check also on the spindle preloading
Good observation! That effect is not from the lathe, but the DTI, they tend to react different when you change the way the stylus is loaded.
That four point adjust chuck is handy. I have a PB adjusttru that has THREE adjustment screws which is a real PITA to adjust!
Beautiful job BTW Stefan 8-)
Just adit 3 more and problem solved 😂
At last, a use for the ball end carbide burrs I've accumulated over the years.
It wasn't always possible to buy individual burrs at realistic price and sets worked out a lot cheaper for the 3~4 I needed in the sets of 6.
Nice looking finish on this part!!
Very interesting and enjoyable. Thanks for sharing
Well done Stefan, that's inspiring. Pushing what you can do with a lathe a bit....at least regarding to what I am used
And here i was waiting to see that inside chamfer get machined on the lathe.
Merry Christmas! Thanks for all the videos in 2020! ⭐️😊👍
Die beste, die beste, nemačka medecina je najbolja na svetu.
Thank you Stefan for another excellent video. Always enjoyable and educational.
Great video as always Stefan, I thoroughly enjoyed this one 👍👍
How tight is the chuck to backplate to be sliding around? Did you tighten it off camera?
Enjoyed...great discussion/demonstration/build
Why do I smile every time Stefan has a little laugh! 1:43 Thanks! (I'm not going to say one word about 23:15)
TsTsTs...und am Anfang schuf Gott die Mittellinie!
Aber Hallo! Ohne Mittellinie ist es nur ein Blechteil ;)
When the chips made a little bird cage round the chuck jaws, I found myself saying "YEEEEW", expecting that's what you were going to say. DAMN, wrong, you said it was fine cause the chips were away from the surface you were working. LOL Always love when ur vids come out. thx from Canada.
Stefan, that you for yet another great video! I can do work like this in my dreams since my ~109-year-old South Bend lathe could never do work like this. ;) But I certainly know how to more properly design & draw a part like this one, including a chamfer (or equal) at the end of the clearance hole at the bottom of a counterbore. And I also have problems looking at bad drawings that don't show centerlines!
Could you click the closed-caption option on all of your videos so those of us with hearing loss can be better able to hear/understand _everything_ you say? This video didn't give me that option, but I believe that I understood everything.
Such high-quality shots throughout. Awesome video Stefan.
Very nice piece of work Stefan, as always. Thank you.
I'm amazed at how quiet the lathe is. Was any modification done to the bearings? Wonderful content in every respect!
Wondering the same thing. I also have a Emco Maximat Super 11 and it’s way louder due to the geared head.
Awe inspiring work as expected, your channel is probably my favorite machining channel of all time!
I had a contract for an antenna relay on the B1B in 1985. The drawing wanted 0.0002" tolerance. None of our machine shop suppliers could meet that. My parts wound up in MRB, material review board, which is jail for parts.
Hello Stefan,
An enjoyable and informative video... Your Zentra six-jaw chuck is very good...
Take care
Paul,,
Oh you indicator needle is not moving eh? Today on Instagram Robin Renzetti said to change your indicator to one with a higher resolution! Good stuff as usual Stefan. BTW I love your lathe too! And Yes I enjoyed this very much, Thank you for posting it for us. Cheers
i have an electronic millitron indicator that has 0,03micron as its smallest increment. But thats truely overkill for this application ;-)
@@StefanGotteswinter
Depending on just how good (or bad) the spindle bearings are that could be an exercise in frustration. Perfect is the enemy of good enough.
@@mpetersen6 And good enough is a brother of a "to the fuck it bucket"!
@@StefanGotteswinter 30nm? Doesn't that pick up the deflection of the floor through the lathe when you move around the room? 🤔
@@StefanGotteswinter I actually have a really old lever-head electronic gauge in the basement which is probably good to such dimensions. I bought it at a flea market for a song and it still has the original carrying case. I wish I could remember who made it, though.
you really should consider the angled Horn supermini inserts for chamfering at some point, especially when using the solid tool post. they come with 45 or 30 degrees and work great even in hardenend steel, i use them all of the time.
Real nice work. You stay safe as well.
this guy in his basement "0.006 tolerance is okay for a hobby lathe"
me at my work "many times even +-0.1 is difficult"
Not gonna lie at first i thought you meant inches and was worried
tune up your lathe clean out gibs and check bearings.. mine can hold tenths...at work we hold that on production runs thousands of parts..
@@miguelcastaneda7236 it's not that simple on a 13 axis lathe. There are 3 or 4 depending on how you look at it. From the later half of 90's. I know that they could be rebuilt but that would solve nothing. The cost and labor would be insane. Buying 2 new to replace those shaisse und 6 other lathes down the line would be much better choice.
Stefan I see you are using a 6 jaw chuck with an unusual regulation to correct eccentricity, where can one get it? Are you happy with it and I am very curious of how it works!
Nice work Stefan! I start searching for CBN inserts as a first! Thank you for this tip. I also like the 3M 3mu cloth for lapping a hard surface! Thank you for that tip too! During the video, and especially on the first shown tolerances on drawing, I thought this part is used in a secret cyber plant or the next mission to mars... Let me ques; a young fellow drew it and didn't have a real clue how hard it is to achieve these tolerances... (on a hobby lathe ;-)). Please make it accurate so I'm not to blame during assembly... Or something around that line. I experienced this many times and tried to add the economics to their equation as well. It worked most of the times. Otherwise, after repeated suggestions, I just follow their drawings and made the quotation or invoice accordingly or live and learn. On the side; you keep mentioning "hobby lathe" and I wondered if you're still self employed as you mentioned in earlier video's? Is there an update on the job side of things or didn't anything change? I'm self employed for 24 years and know the up's and downs by doing so quite well and by doing so thought of a paid job frequently also ( I had a crew running too to put things in perspective). Just curious. Love your dedication and your giggle. No centerline, giggle (=fool!) ;-) I digress, sorry for that, but the end of your video made "everyone(man) likes to get things in a hole" a kind of shallow... A fixture for a Kaiser single point boring head... I'm sorry but Kaiser did the work here to be real accurate as a start and your 1000% guy is the next to be responsible for the final results of his desired hole... I understand what you did and it was safe to show us your anal approach on the matter.. (no offense) I learned and enjoyed! Thank you Stefan. Keep up the nice work, be safe and be happy. I'm inspired by your work, especially on the D-bit grinder where I'm trying to get just as good at as you are. Thank you again and all the best! Job
Hi, an interesting project and of course well made. Thanks for sharing, look forward to your next video
very good video stefan..thanks for your time
We don’t touch it anymore, we don’t talk about it... 😂
I would like to know your opinion of what would be the recommended lathe tool holders to have in a home shop, as is quite difficult to find holders that are smaller than 20x20. Thought about milling down the holders but sounds a bit sketchy
Awesome as always
I'm sure you know about screws that are threaded all the way to the head (a bit more expensive)... possibly a tad of a stress riser there but this may not require a crazy clamping force either.
Really beautiful job Stefan! That was a really fun job to watch :)
I like go/no-go gauges. Does it fit? Yup! IT'S GOOD! Edit: I use 3 mic lapping film to polish fiber optic terminations.
i enjoyed that. thanks for an inspirqation boost.
quick question: regarding the chamfer for the screw 'neck radius' , would that be some kind of fractional/percentage of the thread diameter/nominal bolt/screw size, as some kind of basic guidance? Have a good week, sir!
Probably not, for the most part it's just the radius of the tool that made a relief cut for the thread. If it's a full threaded screw. If it's got a bit of a shoulder, it's the radius of the tool that cut it to size.
I'll hazard a guess for most application the clearance in a plain hole or start chamfer for a threaded one does the job. In a more critical application for you'd probably want to talk to the manufacturer of the fastener to be certain of what to expect and design around it rather than rely on a rule if one exists.
@@Broken_Yugo Generally you'll only see crazy precision screws in medical applications. And space stuff. Maybe aerospace if it's some prototype military thing. Otherwise you'll only see the general purpose screws. Potentially nuclear as well.
You can however make your own screws to what ever spec you want.
Does change in the rake angle make a big difference to the cutting performance after lapping the insert?
Love your videos Stefan! I'm a beginning machinist and was curious about something. After you use the round AlO stone for deburring your chamfer you blew on it with compressed air. Does that blow AlO dust into the spindle bearings, or is there no risk of that?
When you use abrasives, they break down and deposit on surfaces. You blast it with an air hose, that are going to go somewhere. This is a real issue to be aware of and avoid if possible. The quantity here would be minuscule and the spindle bearings are typically protected by double lip seals behind a cover plate, so not a huge concern
Love your videos. could you make a video on round lapping internal and external? woulf be really helpfull.
Hi Stefan. I always wonder about precise indication of runout with needle indicator and angle of needle to direction of rotation. I mean not about sine error, but backlash of needle if it is not in plane of rotation. In worst case scenario, needle is put perpendicular to round part and rotation left and right will make needle "bend" a little left and right. Isn't this best practice to put needle to match its rotation plane to rotation (or translation direction in fact) of measured part? I know it is not always easy, as part being close to jaws makes it hard to put indicator there, but maybe that is the place to use redirection contraption, something like ID measurments with needle indicator? Maybe this is overcomplicated stuff, but since you look up to Robin's excelent work, I thought you might be interested in such details :). I'm curious of your take on this.
If you are criticizing the drawing, the thread definition is missing on both views along with the hidden detail on the full view and there should also be a centre line for the small holes on the large diameter...
Excellent content- as usual !! Thanks, Stefan
I use that 3M paper for honing my woodworking chisels. It leaves a mirror finish.
Thoroughly enjoyed. Thank you.
Beautiful work.Thank you.
Do you adjust the torque on the bolts that hold the chuck to the backplate when you use the adjust true screws?
can you talk about vacuum hardening? Why is it superior and .... would purging o2 with a gas give you the same results?
No, inert atmosphere hardening is not the same. Vacuum is an insulator - there's no convection currents; so the actual thermal profile of the part is more controllable. This prevents the natural up/down convection currents that can cause uneven heating/cooling (and hence lead to warping). There may well be other advantages too; I've never actually used that technique (just have a material scientist's understanding of it; for whatever that's worth ...)
Awesome job! Thanks for sharing!
I love my mitutoyo digital micrometer as well, it doesn't have the quantum speed though
2 micron tolerances on the drawing. :-0
Yeah, we fixed that ;)
Ahh, 1000% guy! Interestingly I was going to offer to send you a bunch of new Arno 1.5mm and 0.5mm carbide end mills that I bought as a job lot at an auction. Then I read on your web page that you didn’t want donations of tooling. So they are on UK eBay instead. If I put an end mill that small in my mill, the result is inevitable.
When the Industrial Engineers at work got their first CAD system in the mid-'80s, the system default was to display dimensions to *6* decimal places and the young Engineers didn't know how to change it (at first). You should have heard the Riggers _scream_ when they got a nice new CAD drawing showing placement of desks & file cabinets to ±x.000000-inches (±~3.9e-8 mm)! ;-D
@@bobvines00 I was outputting gcode to 6dp until I realised that was nanometres. microns are good enough for plywood :D
Those are some crazy tolerances! Are they really necessary?
Hey Stefan 👍 nice job