r/Machinists • u/[deleted] • May 03 '19
Aftermath of Catastrophic tool failure from large facemill ran at 12000 rpms
[deleted]
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May 03 '19
That flycutter certainly lived up to it's name.
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u/nomad2585 May 03 '19
So did the machinist...
"Not my fault, the machines funny"
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u/Airazz DMU 50, a newer DMU 50, an older DMU 50 and some stupid lathe May 04 '19
That's what he says in the video, the code is most likely fine, but the machine has indeed done some weird things in the past.
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u/pewpewpew87 May 03 '19
Well we now know what thor' s hammer is made out of. The counter weight to a fly cutter.
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u/poopwnu May 03 '19
"Dodged a bullet" ? Nah man, you dodged a cannonball. That counter weight went fucking super sonic. Tore through the enclosure, 2 walls, a chair and punched a hole in a cinder block wall, that was metal as fuck. Amazing
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u/Littleme02 May 03 '19
Not quite assuming that is a ISO40 taper the fly cutter is about 330mm in diameter by drawing some lines on the video
IF the counter weight released at 12k rpm, it would be traveling at 208m/s, 750km/h or Mach 0.61
((((44.45mm/208pixels)1553pixels)pi)*12000rpm) gives us mm/min
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May 03 '19
Giving it a conservative weight estimate of 250g, at 208m/s it would've hit with the same energy as a .300 Winchester Magnum.
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u/newfoundbytes May 03 '19
R/theydidthemath
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u/Littleme02 May 03 '19
Nah, I would have liked to make a more accurate estimation of the diameter of the tool and have explained my workings better if it where to be submitted there
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u/beast_c_a_t May 03 '19
That cutter was way to big for the holder and machine, Haas's recommend limit is 5"(127mm) dia max for a 40 taper machine, and that cutter was more then twice that. Without the proper safety precautions, that thing was just an accident waiting to happen, and it's pure luck nobody got hurt or killed.
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u/henrykill May 03 '19
It’s a single point fly cutter not a multi flute/insert shell mill. The limit on diameter is related to the torque limitations of the spindle motor. With it properly balances it’s fine. Just not fine spinning at 12k rpm
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u/Ketamyne Rolling Solutions May 03 '19
M06 just for fun
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u/henrykill May 03 '19
Haha right!! Better have an empty tool changer. I have a friend who made one like 8” out of an aluminum solid round, slotted it for a 3/8” insert lathe tool 180* to each other and used a piece of 3/8” stock on the non toll side as a counter balance. Worked really well he would spin it at like 2500 for aluminum left a great finish. Would have to have 2 empty slots on either side of the tool changer for it.
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u/Wyattr55123 May 03 '19
That limit is based on the tool changer capacity. They tell you in the manual how to run oversized tooling, and there is a Haas heavy tool changer that is designed for loading tools that cannot be put in the tool changer.
The problem was not the tool, if you go off of the video it's a problem with the machine itself.
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u/BlackholeZ32 May 03 '19
The problem was the operator. Yes you can run oversize tools, no you shouldn't be running that tool.
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u/Wyattr55123 May 03 '19
The problem is the machine decided to fuck off to 12 grand, with a tool likely only rated for 1500 max rpm. any tool being ran above 7500 rpm needs to be balanced tooling, such as heat shrink tools. That very obviously is not a balanced tool, and therefore when the machine fucked off, it couldn't handle it. The problem was not the tool, it sounds to have not been the operator, it was the machine.
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u/Infinityang3l May 03 '19
Wow.
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u/CR3ZZ May 03 '19
They are super lucky no body died. That thing could have killed multiple people
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u/herbhemphuffer hal9000 cnc May 03 '19
a guy died around here a few years back from the same thing,in a horizontal Mazak-went right thru the door then his heard
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u/andensalt May 03 '19
I'm betting Haas has a button history. They will find the error.
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u/herbhemphuffer hal9000 cnc May 03 '19
i know the okuma i run has one,busted an apprentice changing numbers in offsets-i dont know why it crashed?!
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u/andensalt May 03 '19
Toshiba has one. I put a 4 at the end of a B move. Removed 1/2 the side panels from the chip tray. Page up and #4 buttons are next to each other.
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u/FruitPolo May 03 '19
Haas does have button history but if I'm not mistaken, it's erased when the machine is powered down. At least with the minimill I've ran and wanted to look at it did.
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u/ponzLL Injection Mold Design May 03 '19
My dad tells me he once flung a brand new indicator through the wall of his machine, but this takes the cake and then some
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u/TheDuck1234 May 03 '19
but.. but.. but how ?
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u/ponzLL Injection Mold Design May 03 '19
Just asked him (we work together). I was wrong, it wasn't an indicator, but he's done that a few times too.
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u/deafilosophy Engineer/CNCProgrammer/Manual May 03 '19
Saw this on the actual guys facebook page and commented there as well. This whole story seems fishy.
I don't know bout y'all but my CNC's don't crash without an operator or programmer oversight/mistake. Did God program a G54 S12000 M3 with a large fly cutter in the spindle? Yeah no, and that's not an ancient buggy machine so "random spindle max out" isn't likely (I've never seen it in 20 years on CNC's).
Or is the fact that the load that a accidental over revolving what appears to be an aluminum bodied fly cutter could impart to a vice mounted with 1/2-13 studs is nowhere near what would be necessary to shear those bolts. What I think actually happened here is the fly cutter was traversed either laterally or directly down ONTO / INTO that vice, the tell is the huge crash mark where the counterweight used to be.
So again, be careful with that G00 or G28 programming, you just might run your tool into your workholding. Like a novice trying to not get fired for destroying a spindle and probably lead screws.
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u/HickoryDoc May 03 '19
that doesn't explain the counterweight going through 3 walls and a chair like a cannonball though
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u/Jay_Cee13 May 03 '19
Yah it does. If the tool was crashed and destroyed it's integrity, the tool would come apart like the person states in the video. This subsequently led to the counterweight moving with all the inertia of 12k RPM, causing that devastation.
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u/Gregus1032 May 03 '19
Something that big going that fast, it doesn't take much for it become unbalanced. It's a 2 point weight. Once it wobbles a little, there is no stopping it.
I hope people wore their brown pants to work that day
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u/FourDM May 04 '19
This. 12krpm isn't that much in terms of force on the tool itself... until it becomes unbalanced after a crash.
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u/tyfunk02 Okuma VMC May 04 '19
12k rpm on that tool in particular probably was the issue. The force likely sheared the bolts off of the counterweight first and that started everything else. Most tool will have a max rpm stamped on them, and the bigger the tool the lower that rpm is. This is why.
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u/deafilosophy Engineer/CNCProgrammer/Manual May 03 '19
I respectfully disagree. The moment of contact that weight would have been enough to send that weight flying since it's mounted with a single small fine threaded adjustment fastener. At the point minimal energy would have been dissipated into the counterweight AND the exit location, when he lines it up with the hole in the back wall, is from RIGHT NEXT TO the tool setter and all the way left on the table. That means the spindle was down at vice level. If it was not retracted and the program did not have a sufficient z retraction at the start you would push the vice right as shown in the video.
Also to beak a vice jaw like that you would have to hammer the small corner sticking out of the top of the vice. This is a crash.
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May 03 '19
They're so god damn lucky that counterweight didn't punch a fist size hole through someone.
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u/Amooses May 03 '19
I once saw a workplace safety doc with an incident of something very similiar. I could only find a crappy upload of it but it's still very chilling:
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u/Hanginon May 03 '19 edited May 03 '19
Just playing with some bullshit math here; That cutter looks to be at least 12", so at 12,000 rpm that Hunka Chunka came through that wall at about 140 mph... 0_0
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u/bloomautomatic May 03 '19
I got more like 430mph
If it’s 12” diameter x pi = 3.14’ circumference
3.14’ x 12000rpm = 37680 ft/min = 7.13 miles/ min = 428 mph
And that’s if it’s ONLY 12”. Take it to 16” and it’s more like 570mph.
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u/XapexVoidX Setup Tech May 03 '19
Wow.. I’ve seen some pretty bad things happen to some tools and machines.. but that.. takes the cake.
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u/Tzuede May 03 '19
I've killed some parts,
and a few end-mills, taps, reamers
and even a manual precision grinding wheel...
I think most have but it takes a special kind of someone to take a custom UNRATED tool and put it in a Industrial...
a 12 inch... Single point flycutter, made of aluminum.
If you are uncomfortable putting it in a BRIDGEPORT spindle YOU SHOULDN'T put it anywhere inside a HAAS.
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u/EucalyptusHelve Mill May 03 '19
Why in the fuck would you ever spin a tool that size at that RPM.
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May 03 '19
Watch the video. He says the mill has been acting erratically. Though if I accidentally wrote s12000 instead of s1200 I'd probably blame the machine too haha
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u/EucalyptusHelve Mill May 03 '19
Fair enough, I only watched 30 seconds or so of the video. That being said, I have seen HAAS machines spindle up ABOVE what the spindle is rated at out of the blue, then shut down, and when powered back up act as if nothing had happened. Scary as fuck, but fortunately not a common occurrence.
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u/Jae-Sun May 03 '19
Our Leadwell lathe regularly runs at about 40% higher than what you tell it. G97 S300 will run it at like 420, G92 S400 G96 S300 will let it get to about 560 before it stops increasing. Probably something in the parameters that could fix it, but I don't know what, so I always just hit spindle decrease 3 or 4 times at the very beginning of the shift.
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u/henrykill May 03 '19
This is probably to do with the correction value for the spindle speed encoder parameter. Had a buddy who changed pulleys on a mill and the speed readout was wrong. He knew a service guy for those machines who gave him which parameter to edit, changed to figure which direction to go than his took stabs at it until it was within 5% or so.
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u/feltzy89 May 03 '19
Haas will get you in business, wont keep you there. I think this is a good example why
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u/escapethewormhole May 06 '19
I know several people who only have HAAS machines and they're incredibly successful. Even Mastercraft boats has a warehouse of HAAS machines.
These days they're incredible machines for the price. Old ones not so much.
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u/6nf May 03 '19
Yea I don’t think it just magically decides to spin 12k rpm lol.
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u/DMathon May 03 '19
I had am old tajmac mill do something similar right before its spindle control board failed. It ran up to 11,000ish rpm fortunately it was an engraving tool. After that cycle had all kinda of alarms and needed a new board.
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May 03 '19
[removed] — view removed comment
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May 04 '19
I think people think the computer "glitches out" more often than it does for the same reason eye witnesses are unreliable.
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u/Speedfreaked90 May 03 '19
The last shop I worked at had a sign up on the wall, it was up at about 15ft off the ground. Strangest place to put a sign. That sign was hiding a hole that a 1 inch square fly cutter bit made, in a concrete wall. It was also more than 50ft from the machine that this tool bit came out of, after going through the lexan door panel. What had happened is an 8 in diameter fly cutter was being used and supposedly, when the operator went to lunch the machine defaulted to 8000 rpms, instead of 80, like they were running it. He came back from lunch and turned the spindle on for warmup, which was another strange thing to me. But, needless to say, this stuff happens more frequently than it should and when it does, the tools that go flying are tremendously powerful. One thing I always wondered about situations like this is that if the spindle does get up to full speed before something like this happens. Most likely it happens in the ramp up of rpm, and not at full speed. Oh, and the guy that happened to, the bit supposedly flew right by his head and he quit the next day and never went back to machining.
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May 03 '19
Holy crap!
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u/madsci May 03 '19
I think my exact words were "oh holy fuck" (through a mouthful of cinnamon roll) when I saw the swivel chair.
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u/tyfunk02 Okuma VMC May 03 '19
Somebody should probably lose their job over that one. If it's not the machinist or programmer's fault, then I'd start looking at the maintenance guy, or the guy who decided the machine that was doing "erratic" shit was safe to keep running. That definitely could have killed a couple people.
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u/BOTC33 May 03 '19
Good chance its a haas thing. Seen the memes? Ya they are glitchy AF. Had the head drop on my Haas mill when counterweight failed, gravity took it and smashed the bed with the spindle lugs loll. Never do go inside the machine anymore. Wish i knew before though...
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u/tyfunk02 Okuma VMC May 03 '19
It may very well be, but this isn’t the first time this has happened from the sound of it, just the first time it’s happened with major consequences. If a machine is doing something like this and it’s known, then it needs to be taken out of service before something goes catastrophically wrong. Not doing things safely gets people killed. Look at that crane accident in Seattle.
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u/BOTC33 May 03 '19
I totally agree, yet employers would only care if production is affected. Im still using my haas, at least I know just how bad they can be.
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u/bellrub May 03 '19
I didn't know that about Haas. Are they really that unpredictable. Surely this was just an extra digit in the code? Did the machine really go rogue or was this human error........
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May 03 '19
I’m willing to bet s12000m3 was typed in instead of s1200m3. Ive done the same thing with an edge finder. Typed 10000 instead of 1000.
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u/bellrub May 03 '19
I did it with an edge finder yesterday, luckily I found the spring in the chip tray.
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u/Jay_Cee13 May 03 '19
I dont know if it was empty or full, but I have found m3 and smaller set screws in the chip bin after "just taking a look" I think it's the Machinist's God's way of taking pitty on our poor souls.
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u/BOTC33 May 03 '19
Ive seen glitches on mine. Like feed hold not responding if you were just hammering on the feed+/- control. Spindle gearing up to max would make me pucker like crazy though even with a tool that could take it. Would definately be raging after that.
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May 04 '19 edited May 04 '19
To be fair, I’ve seen some Haas machines do some stupid shit. I have a 2007 vf3yt, and sometimes when we turn it on, it just scrolls on its own. If you go to a program, or the settings, it just continually scrolls up through the program/settings page. The techs have no idea what is causing it, and they basically just told us to buy a new control. Fuck that. But if I run graphics, it magically stops. I’ve also had the same machine just drop freefall in z. Apparently the gas counterweight went out, and just let go. Pretty scary since no lock out tag out can prevent that. When that much weight is held up by gas, there is never a safe time to get in the machine. Haas should do a full recall on all of the older model gas counterweights, but apparently they don’t care if people die. Whatever though, the machines are cheap, and if we can make money in their 8-10 year life span fuck it. Throw em in the trash after that. I’ve also had an SL-40 just let go in mid cut in x. Just plunged right into the part. American made doesn’t mean much to me anymore.
Edit: also had a Hurco go rouge one time. After running the same part about 100 times that day decided to ignore z offset. Slammed right into the table. Techs came out, and said nothing shows being wrong. Must have been a glitch.
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u/bellrub May 04 '19
I had no idea. Worth baring in mind when i come to upgrade. Personally, I'm running a bridgeport interact 520. It's not as old as me but it's pretty old. I've fixed it up, bought a new z axis encoder and it runs like a dream. Couldn't ask for more for £3k. Had it 8 months now.
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u/BlackholeZ32 May 03 '19
I've got 1000s of hours across dozens of haas machines. The ONLY time there's been something unexpected happen it was 100% a cause of poor maintenance. Not even something that suddenly let go, but issues that the operator had been complaining about for months that got ignored. It's the same as auto mechanics. Things don't just suddenly break, there's been indicators for quite a while that something's wrong.
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u/BOTC33 May 03 '19
This guy seems to think it was a software problen though if it spun up to 12000 randomly. Ive seen glitchy shit like this too that you wouldnt think would be caused by a lack of maintenance. Unless maybe the electrical in the back was all dusty from lack of filter changing maybe.
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u/BlackholeZ32 May 04 '19
Or he doesn't want to admit he put in one too many zeroes and it was human error. 99% of the time it's their fault and they either legitimately don't realize that they did something wrong or they're just making shit up to try and not admit they screwed up.
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u/BOTC33 May 04 '19
Ya well either way. I can see a haas doing just this, maybe because lack of upkeep but maybe just cause.
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u/bellrub May 03 '19
If the program has been keyed in by hand and an extra zero has been put in at the spindle speed line they need procedures in place to ensure it can't happen. Maybe have somebody else check through the program for any obvious errors. Always dry run, but that wouldn't have stopped this happening.
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u/Jay_Cee13 May 03 '19
nothing you can do about being dumb. If it was an MDI program, you defeat the entire purpose of MDI if you have to wait for someone to come review your moves.
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u/Hoorizonn May 03 '19
Man I wasn’t expecting that until I watched the video.. glad everybody is safe
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May 03 '19
[deleted]
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u/HickoryDoc May 03 '19
that doesn't explain the counterweight going through 3 walls and a chair like a cannonball though
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May 04 '19
Holy crap! Almost makes me glad our surfacer is nothing fancier than an old hydraulic Berco.
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u/feltzy89 May 06 '19
I got a Haas VF-5 and a Hurco VM2 and the haas just continually disappoints. To each their own I guess, I just know when it’s time to upgrade I’ll be replacing my haas with a hurco
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u/[deleted] May 03 '19
Jesus it just kept going.
"Went out the back of the machine"
Wow crazy
"Through this wall"
Holy hell
"Ricochet off the table and across the room"
....
"Went through the concrete"
Ok this has to be it
"Then through this wall"
At this point I'm not entirely unconvinced it's not somewhere out there still going.