Turning Steel Cones on CNC Lathe! Widget86
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- čas přidán 28. 03. 2016
- Using Fusion 360 CAM and the Tormach Slant-Pro CNC Lathe to turn 6" 1045 Cold Rolled Steel Cones. Facing, Boring and Profiling! And failing to activate the carbide insert chipbreaker!
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lower the rpm, increase the feed and increase depth of cut to stop making wire
john hancock finally someone who knows something
@@triplem451 yes but the tormach lathe doesn't have the hp to run more depth of cut at a lower rpm. Can't handle the chipload
Chip breaker 101, at least the quick and by no means complete version. You need to have a DOC greater than your tool nose radius at the very minimum with non self-breaking materials like steel, where brass would be a self breaking material. Then dependent on the chip breaker you are using you will need a feed rate of at least one third of the tool nose radius per rev. Generally the softer the material the higher these parameters need to be to get a chip to break. You a using a CNMG 432 insert, that 2 at the end is the radius in 1/64 of an inch so you have a tool nose radius of 1/32 of an inch or .03125" so your both your DOC needed to be a minimum of .03125 and a feed .0104" per rev to get even close to getting the chips to start forming. In a soft steel like 1045 CR you would probably need a depth of cut closer to .05" so get chip formation. If you do not have the power, rigidity or even that much material to remove then I would recommend going to a smaller tool nose radius. A small nose radius also will reduce your tool radial tool pressure some what. On a machine like the tormach I would use a #1 tool nose radius as my primary tool radius everything only going to a #2 for strength in interrupted turning.
For more info I would read this book published by sandvik as it's probably one of the best insert turning resources that you're going to find. They have a lot of other great publications of this nature on there web site as well.
www.sandvik.coromant.com/_layouts/15/tibp/downloadshandler.ashx?url=gen-sandvik.ecbook.se/eccatalogues/download/247/?lt=false&fileName=Turning%20Handbook
+NYC CNC -- ROC have to be atleeeeeast the tools nose radius. *** Pls consider the depth of cut and feedrate to be suitable for your choice of insert... -- I usually run a 22HP Okuma Lu15 lathe and have great experience with (for stainless), insert: Sandvik CNMM 120412-QR-2025, 8mm depth of cut (16mm on the diameter), Vc=140 (again metric, sorrrryy..) and F0.27 :D ---- how many HP have you got on that spindle??
+Bruno Hougaard that's 1.4044 (316) stainless btw :b
was just going to say that he needs to push that tool harder, lol. Need to talk to Abom79, he may run manual lathes, but the fundamentals are the same
+Josh Peterson yes, indeed
John I have a small Haas lathe in my garage(running on 230 volt single phase) and have the same problem breaking chips in bigger diameter parts. Your problem is you cant take a deep enough cut at the feed required to break the chip without stalling the spindle. You are taking what for bigger machines would be considered a finish cut but using a style of insert they would use for roughing. It wont work on your lathe. What you need is to use a finishing style insert with a low feed chip breaker and smaller tip radius. There are many different types of chip breaker styles on inserts you just have to try them until you get what you want in chip control. I see in the comments people giving this and that advice but this is something that has so many variables you really cant say just do this and it will work. Your set up your coolant, coolant pressure, depth of cut, feed rate, spindle power, machine rigidity, material your cutting to name a few. You just have to experiment an with experience on your equipment you will find out what works for you.
So I can't find the tormach option for a atc on the slant pro....where did you get it?
In order for the chipbreaker to work, you have to keep your DOC deeper than the nose radius on the insert.
That means that a 432 insert needs a DOC of no less than 0.062" (off the OD). Full stop. Anything else you do is pointless until you get the DOC over the nose radius (otherwise the chip never TOUCHES the chipbreaker).
Since your machine obviously can't take a 0.100" DOC at 0.015 IPR like you'd need to in order to break a chip with a 432 insert, you're going to have to go to an insert with a smaller nose radius.
Find some 431 or 4305 inserts and run them at ~120% of the cutting data you used here. Should make nice little chips, and use less horsepower than these cuts did.
Birds nests always mean you're loading the insert too lightly for the combination of nose radius and chipbreaker. If you can't reduce the nose radius and you can't increase the DOC, then decrease the SFM and INCREASE the FPR until it breaks the chip or stalls the machine (or your surface finish/size goes to hell).
Letting a job run with horrific birds nests like you did here is dangerous as hell, even for the machine (especially running that four jaw with the jaws hanging out like they were). Total snaggle and boom fest just waiting to happen.
BTW, if you want to know where to start with SFM, DOC, and IPR on any standard carbide insert, flip the package over and read the label. The MFG went to great pains and not insignificant expense to supply you with those operating range numbers, you might as well learn what they mean and use them.
+LogicIndustries All very good advice! Glad someone took the time to write it up. These lathes are great for bar work but anything over 1" dia and you start to have a serious lack of horsepower making it much harder to control the chips. Personally I'd rather have a minor birds nest than stall the spindle... *sigh* Tormach life.
+NYC CNC Gotta pay close attention to what they actually state the nose radius is, because there really isn't any standard nomenclature to denote nose radii under 1/64" (what the 1 in 431 means).
Once you go below 1, the standard gets a little hazy and different manufacturers note the smaller radii differently.
For example, ISCAR doesn't offer a 05 corner radius, they go straight from 1 to 0, which is what they call their 0.005" corner radius. So for ISCAR tools you'll want a 430.
But then, SECO's 430 insert has a 0.008" corner radius, and Carboloy doesn't even use the inch version of the ISO nomenclature, preferring to use the metric spec for their inserts, which means a CNMG-431 from Carboloy would be called a CNMG-120404 (80° diamond shape, zero side clearance, as-molded medium tolerance class, double sided with chipbreaker and center hole, 1/2" inscribed circle, 3/16" thick, 1/64" or 0.015" corner radius).
So if you wanted a corner radius under 1/64" from Carboloy you'd call for a 120402 (0.008" or 0.2mm radius), or a 120400 (they say zero radius, but the tolerance class means you could have anywhere from actual zero radius all the way up to a 0.003" radius).
Kennametal uses inch nomenclature and goes from 431 (0.015" rad) to 43.5 (0.008" rad) to 430 (0.004" rad) all the way down to 43X0 (0.0015" rad).
Essentially, every manufacturer has their own way of dealing with nose radii under 1/64", so your best bet is to decide which MFG you want to deal with (like which grade and chipbreaker you like the best) and then download their catalog and see how they name their inserts. Then you can search eBay for what you want with a lot more confidence that you'll actually find something.
Otherwise, you'll have a hell of a time trying to find what you're after.
Also, for your application, just skip right over anything that is designed for roughing or even medium turning. Your little lathe just doesn't have the HP to properly use those geometries (and they won't be offered in the sharp nose radii anyway, because the sharper the nose radii, the faster it burns off when you're taking a heavy cut).
Stick to grades and chipbreakers made for finishing in hard to chip materials like stainless and superalloys. Those seem to be the grades that turn up the most on the surplus market anyway, so that's a lucky break for you.
If the packaging doesn't have speed, feed, and DOC recommendations on the back label, go download the MFG's catalog and look up the grade and chipbreaker, the cutting data should be listed there as well. Heed their suggestions, they know what it takes to make their tools work at their peak.
+LogicIndustries
Thanks for the write up learned a lot just have to convert your USA specs to european codes ours look like EG CCxx ( xx = MT or GT ) CCGT 060202 ALU AK10 Carbide Inserts for Turning Ground and Polished for Aluminium Uni-tip this is a 0.02 mm rad tip,
yes I know they are small but i have less HP than John so you go with what you have ( my shop is a pure hobby shop no paid work )
Do you have a video where you prepare the CAM for this? I'm in the process of prepping our FANUC controlled lathe for drilling/tapping/boring. Drilling/Tapping sorted, just boring now!
Any software tuts on the boring side would be most appreciated.
Keep up the good work!
Do you always switch the pully when you use the chuck? Seems like a mega pain if you go back and forth with the chuck/5c a lot.
Just now starting to learn how to program a CNC Lathe manually and this video spotlighted the need for understanding tool geometry on the lathe. Have yet to actually run a program that is cutting material but I'll be sure to go back and take a look at my feeds DOC and speeds before I do. Thanks for the video!
Would it be good to take all the shavings from machining the parts and melt them down into new stock or use is to cast objects?
Enjoyed seeing the lathe chew up some steel..
Great video man, after 11yrs in a shop I really feel ready to take risks and venture off on my own and these videos really help keep me inspired. Keep it up!
Good luck with the move and thanks for all the work in putting these great videos out!
Setting up an aviary? Those bird's nests are fantastic.
(All kidding a side, I've always enjoyed your Widget series)
big thank you for these vids john:) some of us are so new that we wouldnt recognize how bad the chipbreaking was so, lol. keep that in mind and keep making these because they are valued and appreciated. sincere thanks:)
how bad was your insert drill chattering on the manual lathe, how did you center it? I have a 10x22, wondering if it will work before i buy one.
why is your channel named saunixcnc, any relation to linux?
Like the feeds & speeds tips. Great job
You are so humble, I like that!!!
Everyone has different preferences. For myself on something like 1045 id pull atleast .060 a side with a sfm of 315 plus and a fees of atleast .010 to .018 depending on the insert. Didnt hear exactly what insert you had but my most common one used is a CNMG 432 and my standard is 350sfm .011 feed .060-.080 DOC
un trabajo fantastico, gracias por compartir, un cordial saludo.
gotta working on your chipping for sure try 450sf @.012fpr @ .06"doc leave .005" doc for finish pass @ 750sf or more.
i don't know your tool nose radius or the hp of your lathe though.
Congrats on the last two pieces in the old new shop! Excellent surface finish. There's a bit of excitement like a high wire act when making parts that have no scrap!
Speaking (loosely) of chips: Horrible Stringy Bastards would be a pretty good name for a violin quartet.
Good looking parts, John!
Hey John, you might want to look up what a Modulated Tool Path is. Its a relatively simple way to break a chip without taking a larger DOC or increasing your feeds.
Use that through coolant hole in the boring bar, it really works to break the chips!!
As for feeds an DOC, the DOC should be at least 1/2 your nose radius, preferably closer to the nose radius. The feed rate also depends on the chipbreaker geometry, some are made for roughing and have a much larger gullet, others are for fine finishing and have an upturned edge with no land. You need to feed hard enough to get it over the land and into the gullet. From a simplistic standpoint, try a feed rate value that is greater than the land width of the edge (a measuring lupe can help with determining the land width).
Good job John, you got the parts done on size. You have a starting point now to experiment with your DOC and feed rate. I was told that you need to make sure your DOC was greater than the radius of your insert for effective material removal.
Very good job look forward to your open house. As far as chip breaker inserts going to be going to the same class you are.
i am your big fan keep it up and educate us thank you
What were these parts for ?
Dept of cut you used?
on a cnmg 432 in mild I've run 900 sfm .1874 doc and .018 feed I thing that may stall you machine
The machine would fit great, for the lathe tooling i need for my spinnings.
Id love to send you a 3d model, and see it done on the Tormach lathe.
Why not rough mill the majority of the material first, then bore and finish the cone after?
@ 9:09 you need to increase your feed so the chip is more square, the ratio you have now is 3 to 1 with the 0.005 per rev make it more like 0.015 and you may need to play with the SFM to get the right load on the machine. Your depth of cut should be at least 2/3 of the nose radius of your tool, if not much deeper (HP limited).
KEEP THE GOOD WORK UP
I need some cones for larger rims for my tire balancer ! 9" I believe.
I'd have run that rouging pass at 400SFM, .025-040 DOC, 0.015 feed. But it depends on how much HP you have. IIRC my old Hardinge CHNC-1 would do that cut, but it's 10HP.
I realy enjoyed watching your Tormach run. I think I may have told you in an e-mail that I am a high school machine shop teacher. We have no CNC machines, despite my best efforts to change that.
I have run CNC equipment in machine shops. My experiences with CNC lathes involve parts in the 4000 - 6000 lb range, cutting rolls used in steel mills. Sadly the stuff I was running were clapped out conventional lathes that had been retrofired for CNC a long time ago. I hated every machine I ran there. Not one was capable of making good parts without constantly playing games. Fortunately rolls for mill work are essentially junk!
All the Best!
Mike
East Palestine, Ohio
When I say retrofit they were most likely old paper tape reading NC machines. Converted to full CNC. They were very sloppy and could not hold tolerance from one diameter on the roll to the next. The pieces we were turning were old mill rolls. We would undercut them, send them to the other end of the shop for sub arc welding and then we would re-cut them. The material was of such inconsistent hardness that they were a nightmare to cut.
Depending on hp with a 432 i run
.08 to .125 depth of cut per side and feed of .008 to .012. Never have stringy chips on rough passes
It's great to see small business's growing and thriving.
i have some Mitsubishi cnmgs and a few different sandvik inserts i will bring down to your open house, going to try and bring one of the hydraulic press molds i manufacture as well for the show and tell provided my customer doesnt need it before my actual deadline.
Dean
hay john what might help would be a v sires insert or a 35 degree because the Tormach might not have the horse power to take advantage of an insert like a e,s,c or a w model because of the tip radius being to large for your machine to make a good chip yes the lathe can turn up to 1200 rpm but in truing you learn that its all about tool pressure. you have to push the chip to breaker in order to break a chip
i have a part like this to machine but they want no hole, no center drill, how you hold them?? can anybody give me an advice
fatmachinist fataman make the piece leaving a little spigot for a center drill hole. when done face the spigot off. if you have the same thing for other side, do the same thing but leave enough to grab by with jaws, and when done, face it off.
cool machine！what is the most precision tolerance can the machine make？
The only way I've been able to break chips on a facing cut is to be very aggressive on the feed. CSS is your friend, but you really gotta turn the feed up in order to get the chipbreaker to do its job.
thanks...how much this CNC Turning Machine ?
Cool part and great video! Not sure what you can do about it but theres a high pitch tone sometimes when making cuts that really bugged me even with the volume turned way down. Perhaps you can selectively remove this frequency range when it happens in the future. Thanks! Can't wait to see what comes out of the new shop!
Just about missed this with the different thumbnail! Would you not have had a bit less runout if you had flipped the piece after truing the first face? That should have split the difference between any chuck to tool holder gantry play.?.
Good Christmas video. Like die hard.
the chip breaking strategy i agree with other but also the tool stick out seems to me a bit much from what i have seen in the video
Can you make something like this if I give you the dimensions?
Love the high frequency ear piercing shrill :P
whats the price of machine
in india
from personal experience you have to take far more aggressive cuts with steel than that to make any sort of acceptable chips on the lathe. It took me a year of birds nesting 01 tooling steel every day before i realized it wasn't my inserts or material, it was my feed and depth of cut. You've gotta run faster, and harder. Not sure however if a tormach is the machine for that.
The bird's nest at the approx 9 min mark should have Abom79 rocking in the corner in horror ;)
+Firstly Last No, until then he was just yelling at the monitor and slapping his forehead...
When it comes to roughing out, its feed rates that make you money, not RPM, on mild steel, (on a slightly bigger lathe) I take about 15tho a rev at least 100tho deep a side.
great job!it's so easy for people to nit pick but you got the job done.On your own time you can play with your feeds and speeds.i don't think this video was about chip breakage.
I have a little tip for getting that chip to break if your hogging out some material. When you are drilling a hole, you don't feed constant. You peck it. The same idea works on a lathe. I haven't done it on cnc but when using a manual lathe and I am hogging/roughing out material, I feed about half an inch or so (depending on diameter of work piece), back up a few thou, feed, back up a few thou to get that chip to break so I don't birds nest. It isn't ideal because it can hurt cycle times, but if your machine can't run the ideal feeds and speed for breaking the chip, it can get you by.
That I couldn't tell you. I have never used cam software before. I can say that it does work great on a manual lathe when hogging long/large diameter pieces that generate a large volume of chips per pass. One other tip, the reason I back it up slightly is because if you just pause, you tend to get some rubbing and chatter when your DOC slowly goes to zero.
To break the chip, I find that a bigger feed and depth of cut works. the bigger feed makes the chip curl into itself, breaking and separating itself. Higher depth of cut makes it harder to curl and more brittle. we make a steel part where we have to take it from 2" down to .5". We use ISCAR Sumotec inserts and take a .125" doc, at a pretty good feed, which I can't remember. Give it all the machine has, you will experience better surface finish and faster cycle times
also try using a 431 instead of 432 radius it cuts a little better on the tormach slant
judging by your stringy chips i would throw the cutting speed down a bit, take bigger cuts (if possible) and a higher feedrate also shortens your chiplength in most cases
thanks.
Have chipbreaking issues John?? Kennametal has been pretty nice to me. You oughta talk to one of their application guys.
+NYC CNC You want me to get you in contact with my rep so YOUR rep gets his act in gear? That is unacceptable. I literally run ALL iscar tooling (besides endmills) and our rep takes care of us literally any time of day.
why use a chip breaking setting when ou could just make a swath hook? Now with just 25% chance of losing a limb!
Oh, on chip breaking. Since I do not use a CNC for anything at my current job 'cept for the surface grinder, I do it one old way, that being to stop/pull back/stepping (or whatever one wants to call it)... I talking of drilling here also. It takes longer, but for non-production, it works to keep the chips smaller and the coolant usage down.
Too late for you now, but you would have LOVED seeing things being made in the Lewis Research Center (I think it is called the Glenn Research Center now) back in the sixties. The art of machining was often times at the level of still using mechanical indexing. And it took slide rules and a lot of patience. Imagine if you can a throw of a dozen of feet on a vertical lathe and getting it to a thousandth of an inch!
Great video,these people keep crying about the chip breakage ,it takes time to get the chip breakage right with adjustments and i dont think this video was about making adjustments to get a good chip breakage, great job bud
Probably a stupid idea, but couldn't you setup the CAM so the tool "pecks", similarly to how you drill on the CNC.
This is why you always do an op0 and start by facing off both sides and turn down the od far enough to get a clean cut to indicate from without interfering with the jaws for the side you are going to Chuck up for op one. This creates a slug you only have to play with and flip once and should make it easy to get a completely concentric part without having to waste time reworking a part 6 times to get it in spec
[FIRST] Far out massive parts that I wonder what they are, other than purdy! Very cool vid. Congrats on the last waltz in the old shop and the new adventure. Did I make the cut on the clamps you ate making? I forgot...
change your depth of cut to .045, chipbreakers need to be removing enough material to be effective
hi john
for chipbreaking speeds you should run the lathe at 700-1200 rpm and the feed should be 0.01 per rev and the depth of cut should be 0.05 per side at least
good luck
To get really proper chip breaking you'd need to run so deep doc, high feed or both that I don't think the tormach could handle that. At least with some tools.
the secret is all with the coolant flow. chips are blue :( but considering that machine I say it works well. also it's important to use different tooling for rough and finish passes.
Not sure I completely agree with some people saying min doc of .062 but from what I see your sfm seems a bit high. I would have ran 550 sfm. 005 feed at .03 doc.
It is a very small machine, you can not control the chips reducing the rpm and increasing depth and feed.
john great video but you do need to look at chip breaking or it will be tool breaking! talk to abom79 or oxtool love the foot notes on tools and speeds to go along with the finish. Bill
There's time when you get a good chip breakage no matter what you try depending on the machine or the material you are cutting,don't worry about just get the job done!
How are you liking qualichem?
+NYC CNC yeah I'm starting to wonder. The guy who does my lathe work said he's changing everything to vegetable based stuff just because eh doesn't like the idea of having anything else hanging in the air. I'm guessing most things do better than that clear stuff
smaller Radius of edge in inserts should make chips more fragile :) i used 1.2R on boring inserts and birds nest everywhere ...but when i switched for 0.8 no birds nest nowhere .....or try making faster feed (F) try 0.3 or 0.35 on face
This lathe is really weak. How much kW has it?
heizerbirne your comment sucks
not really...
heizerbirne i think you are right. Just listen to the engine sound, when the turning powers increase. Doesnt Sound very stable
exactly
prob el cheapo made
the lathe is to light duty to push it in order to break the chip on a big piece like that.and that isn't a big piece for that matter. but nice that its being done with patience.:)
Incase your cnc lathe has enough Power put the Vc to 180 m/min and the feedrate to 0.35 mm/min and depth of cut about 2-5 then you should get good surface and good chips works on mine very good and I use a 80 degree plate with a 0.8mm radius kn the tip
"When is chatter ok? Never."
9:10 Hmm.
--
No 4 jaw independent? Wut?
I'm not master (heh, that's an exaggeration, I run a tiny lathe with HSS), but it seems like if you need more feed rate to break the chip, shouldn't you slow down the speed if you you don't have the power to run the higher feed rate?
Ahh, so the CNC lathes run a VFD type setup, and not variable speed pulleys? I see. That is one advantage of a conventional lathe.
OBTW, go to latheinserts.com and get some proper inserts. I'm not so confident in the inserts that Shar's and Tormach sell -- they are targeting low cost inserts and hobby level users, hobbyists typically don't see the value in spending money on good inserts. You can also call the guy that runs that site and get his recommendations.
lol@a copy of chip breakers for dummies..
Gotta say, that gave me a good chuckle!
Hey, just look at it this way.. Now you get free steel wool :D
Abom79 has a pretty decent introduction to chip control / chip breaking on his channel, might want to check that out .
I had an experience with cnmg . In the shop we always use quite low values/parameters .
So i went to grab an insert for roughing CNMG for steel , 0.8mm nose radius . And i saw on the little box the recommended cutting parameters .As i mentioned we usually stay well under those parameters , but i said fuck it lets's kill the steel .
I entered the following values , feed 0.3mm/rev , depth of cut 1.5mm (3mm dia) , Vc 310m/min . It made absoluteley brilliant chips , but i had a 50% spindle load on a 16.5Kw lathe :hehe
sounds awesome :-)
I have to agree with alot of the other comments here. Higher feedrate. And are you really using the right insert for that type of material? Keep up the good work though. I start to get jelly! :D
On manual lathes a brush shaped like a toothbrush will drag chips away from the work. I assume it would work well on CNC lathes as well. To get a very fine finish do not make one finish cut. The metal underneath the working layer can be disturbed by the pressure on the tool point. Make three or four very thin final passes. The chip will be so foil like that it will break onits own and the metal finish will be so shiny that it will look like a CD disk surface. This works even better on aluminum.
Not sure if you will have enough power to break the chip, you need to feed much faster as said. Only buy carbide shank boring bars of that length to reduce chatter. If you don't have enough power to break the chip conventionaly, modify the code to dwell every .01" of cut to make the chips more manageable.
See if your cam package has a chip breaking option like this: czcams.com/video/Adboz_gXdtw/video.html
Would agree with doc. Needs to be larger then tool nose. Feed should be up closer to .010-.015 for light hp. Double check your insert sfm. Should be 500 or less in steel. Strings look awfully blue
+NYC CNC I believe so. Check your inserts but most of our steel inserts we run at the 300-500 sfm. Blue with coolant to me is way to high on sfm. For fun try 450 sfm, .03 doc (or at least your tool nose) .010 ipr and choke up on that tool holder. Need to form a large enough chip to curl off the chip breaker.
basic rule of thumb if you want to break that chip go harder.
practice on your manual machine to get a feel for it.
you want a chip that looks like a little 6 or c.
Try depth of cut and feed speed.
As you know chips like that can wreck your finish keep up the good work!!
its a strange looking cnc lathe that tormach, however nice work!
OD tool is extended too much !
Try using 0.4mm nose radius inserts even for roughing , they can take at least 1mm D.O.C , 0.15-0.2mm/rev feed , speeds depending but at least Vc 200m/min , while providing chipbreaking .
You are using a 0.006 feed rate (0.15mm), I would use a .20 -.25mm feed rate which is roughly .008-.010 in inches. About 500rpm is plenty. A depth of at least 2mm would be ideal, any less and the cut will be smaller than the radius of the nose of the insert.
Good luck moving!
what are they trying to suppress a cannon?!? haha great video as ususal
chip breaking goes with feed and speed
John, would be nice to make a new video if you've solved the birds nest problem and showing us your solution :-)
Looks like a cone for a tire balancing machine.
It's extremely dangerous if the swarf does not break and becomes long. It could wrap around the chuck or turret and break the lathe. For roughing, slow the rpm(material dependant) and increase the feed.DOC depends on what the machine can handle,generally not more than a third of the length of the cutting edge of the insert.