machine shop horror stories

[Al Skierkiewicz]

When I was taking a shop class in college, the lathes were back to back in rows. I was just lucky enough to drop something on the floor (tool or drawing). As I bent to pick it up, the guy at the lathe in the next row turned it on with the chuck handle in place. It went flying overhead where my head and upper body had been. I am alive today because I can't hold onto things. (They don't let me climb towers either.) Needless to say, that guy failed the class.

[EricH]

I was taking a shop class at a community college, and we were all tramming in mill heads. Somebody turned on the mill to move the sweep bar to the other side (you're supposed to just grab it and swing it). 18" long sweep bar... gauge on the end... spinning at whatever the mill was set to. This lasted a couple of seconds at the most before somebody got to the power switch, but the damage was done.

Nobody got hurt, but the gauge was ruined, and the student didn't come back after that, whether by his own choice or by the instructor's I don't know. I found the needle at the near end of the shop; I think the glass or part of it was near the chip bin near where I'd been a few minutes earlier.

[Christopher149]

It was in woodshop, and someone (I don't remember who) was sanding a piece of wood on an oscillating vertical sander, when it caught and was flung into the top of a nearby band-saw. Thankfully the band-saw had a large upper structure so the wood hit only it - and not any person. But it was Loud.

Now, in Robotics, there haven't been any serious incidents, just the usual scrapes. Ironically, First Aid is in the cutting drawer...

[ThatHubrexGuy]

Well... No serious injuries... But I busted my knuckle open with a wrench while doing some lathe work. Did I get a band-aid? Hahaha no. I just kept wiping the blood on my pants. I really wanted to get that part done!

[lil'est lavery]

We've had a girl get her fingers broken in a gearbox.
There was another story (not on our team), either last year or the year before, where a girl got her hair caught in a machine, managed to not get her face pulled in because her hand got pulled in first. She tried to pull her hair out with her hand, which got pulled into the machine with her hair and she lost most of her fingers.

[PAR_WIG1350]

Someone, somewhere was filing down an good sized chunk of metal on a belt sander-like device and lost his grip sending the part about 15 feet across the room missing his son's head by about half a foot.

[Kevin Sevcik]

Way way back at the dawn of time when our team was young... (10 years ago) We got to build in the machine shop at the Land Machines Division of Brown & Root. AND they let us use their nice lathes and mills. With those nifty speedy chuck keys and everything. Then there was the day we all heard a gigantic bang from the lathe area. High speed flying chuck keys are terrifying and loud when they hit the wall. But that wasn't what got use restricted to spring loaded safety keys. It was the second time the key was left in the lathe and (luckily) stayed in long enough to be violently slammed into the ways and visibly bent. So yeah, everyone please remember that lathes are one of the most dangerous machine tools you'll encounter. And keep your hand on the chuck key whenever it's in the chuck. If you never let it go till it's out of the chuck, it's stupendously less likely to take flight.

Unrelated to FRC, but we recently had a close call at my workplace. A welding positioner about the size of the attached photo was being anchored to the concrete when one of the anchors failed and the whole thing fell forward, narrowly missing one of our shop hands. Obviously an extremely serious incident and we're making some changes around the shop to prevent any reoccurrences. So any of you working in industrial shops, do remember to be wary of the big machines around you.

[Hawiian Cadder]

a few years ago someone was using the mill and the wrench up there, the mill spin it up to 2400 rpm and then it shot off the top, nobody was hurt but it traveled about 100 feet across the shop

[SirTasty]

One of our teammates was working on a scissor lift prototype and accidentally dropped it on his finger. Cut it really deeply, maybe all the way to the bone. Never let programmers near metal.

[Tristan Lall]

Here are some related threads from deep in the archives (not all are entirely about machining):

team emergencies
First Injuries
Grady personal injury avoidance tip #2
Injuries
were there robot related injuries on your team?
pic: When Waterjets Get Nasty
pic: Waterjet nastiness Dermilogical Effects -face
FIRST Injuries
Serious Safety Incident - Please read to your teams

Originally Posted by Al Skierkiewicz

It went flying overhead where my head and upper body had been. I am alive today because I can't hold onto things.

In grade 7 or 8 shop class, someone* nearly did the same to me. He was using a drill press with a fixed cable or chain tied to the chuck key, presumably so as not to lose it—that's an idiotic convenience feature, by the way—and managed to forget the key in the chuck. Upon starting the drill press, it of course got tangled, then broke off and went flying at the spot where I'd been kneeling to pick something up a few seconds before.

Fortunately, an average drill chuck key can't do as much damage as an average lathe chuck key, so I would have been in rather less danger. He didn't fail; the embarrassment was probably sufficient to cement the lesson.

Originally Posted by Revant54

I remember about 3 years ago(I was a Freshman at the time), and I was drilling into a piece of diamond plate. Being a Freshman at the time, and not to bright in the machining sense; I didn't use anything to lock the plate down. To add to this initial dilemma, I unknowingly was drilling a bit too hard into the plate, and ultimately the plate got stuck in the bit, causing the plate to spin with the bit, resulting in my hands getting badly cut.

I've done something close to this—as a high school student working rather late one evening to finish off a robot. In my case, all that resulted were a few little scratches and bruises, rather than cuts. It had a lot to do with not realizing that a drill bit (especially a dull one) would catch on to the rough edge at the bottom of a hole in an aluminum plate. This caused it to lift up when I finished drilling the hole out to its finished size. So of course, the 4 in × 8 in × 0.25 in gearbox plate that I'd been working so hard to finish got picked up by the drill bit, unbalancing it; that wobbled around at a few hundred revolutions per minute for a second or so (hence the shallow and essentially bloodless scrapes on my hands), and then sheared the drill bit off, sending the plate glancing off my chest and into a pile of detritus underneath another piece of machinery. I was in no way seriously injured. Despite that fact, that's not a mistake I aim to make again.

Originally Posted by Kevin Sevcik

And keep your hand on the chuck key whenever it's in the chuck. If you never let it go till it's out of the chuck, it's stupendously less likely to take flight.

Originally Posted by Hawiian Cadder

a few years ago someone was using the mill and the wrench up there, the mill spin it up to 2400 rpm and then it shot off the top, nobody was hurt but it traveled about 100 feet across the shop

Speaking of mistakes I don't aim to make again, avoid leaving the wrench on the drawbar nut of a Bridgeport 2J2 knee mill. No injuries that time, because fortunately the spindle could only advance a half-turn before the wrench hit the motor housing and unseated itself loudly, falling straight to the ground. Like a lathe chuck key, thats a piece of equipment that should not leave your hand while engaged in a moving part, and which deserves to have a well-defined place in your line of sight when you're reaching for the power switch. (This milling machine—like most—was not set up that way: the wrench lived on the right-hand side of the machine, behind the quill lever and partially obscured by the digital readout, while the power switch was located on the upper left of the mill head.)

*He has a ChiefDelphi account, although he didn't at the time.

[JDL]

I have some good ones from my real world job (electrician).

Now on our team no, even though I'm accused of being to lax with team safety (I really don't see why people feel the need to tell the guy how works on live switchgear and around industrial equipment all the time how to handle safety but whatever). No flying chuck keys, no eye injuries, no entanglements, just the occasional splinter and minor cut.

[Al Skierkiewicz]

JDL,
Someday I would like to hear some of those stories in person.

[Karibou]

Originally Posted by Kevin Sevcik

High speed flying chuck keys are terrifying and loud when they hit the wall.

Or anything else, for that matter. From the two or three times (over four years) I've accidentally had the key fly out, I'm convinced that the chuck key exiting the chuck also creates a terrifying bang.

Originally Posted by Kevin Sevcik

So yeah, everyone please remember that lathes are one of the most dangerous machine tools you'll encounter. And keep your hand on the chuck key whenever it's in the chuck. If you never let it go till it's out of the chuck, it's stupendously less likely to take flight.

I can't echo this enough - I'm my team's main lather operator, and I've learned that those things are horrendously dangerous. Chuck keys are one among the many things that can go flying if the operator isn't careful. Please also remember to make sure that whatever is chucked up is in there TIGHTLY. If you start cutting and hear a clunk, stop the lathe and check to make sure the metal (or PVC, or plastic, or whatever you're cutting) hasn't slipped. Make sure that the material is in there straight, and that EVERYTHING is squared up. You definitely don't want your material to slip out and hit you in the face. I'm sure it hurts.

One more lathe safety thing: even though we don't want chuck keys flying at all, make sure that the area in front of and behind the chuck are clear. Nobody should be standing in the area in front of and behind the chuck, including you. Take a step to the left or right before you turn the machine on.

----

I've had a few close calls myself, but thankfully nothing horribly bloody. Freshman year, I managed to tear off about a quarter of my fingernail on the lathe, and I'm still not entirely sure how it happened, but I think my finger got hit by part of the chuck somehow. I also currently have some small burns from hot metal chips hitting my skin. It's painful.

I was also drilling a hole in a piece of extruded aluminum that I had clamped in a vice, and the drill bit got caught on the metal. It spun the entire vice around and took a good amount of skin off of my left wrist, which was the hand that was holding the vice. No blood, but it was very painful, and I still have the scar. Always clamp things down to the table when working with machinery!

[fox46]

The other day, my boss, while showing a group of students from the team how a surface grinder works fired a sprocket into a wall about 10 ft away. We had anticipated the risk though and everyone was standing well back. They now have a beautifully waterjet oval sprocket as a reminder to respect machines.