Next time I machine a 6 foot barrel, I will be more careful so this doesn't happen.

It seems that the safety standards are working to top efficiency.

Darwin is clearly hard at work, keeping the gene pool free of genetic, biological hazards and abnormalities !

Unfortunate. Should have learned about that problem in his trade school.

The main thing they taught us in trade school, safety wise, was not to leave your chuck key in the chuck. One guy did and broke a window; fortunately not hitting anyone.

Yep. Whole chuck key thing is very important. Drummed it into us. Teacher was very experienced. On the tail stock side of the Chuck the steady rest and or follow rest are helpful. In the case that got this kid we used a steady rest as well. It was mounted on the bed of the mill to the left of the lathe. Slightly modified base to fit the mill bed T-slot but was adjustable in all three axis thanks to the mill.

I have my mill set to the left of my lathe. Have never repeated the set-up but can it I need to.

Left the chuck key in the drill press a couple months ago. Lucky it was on a slow speed. Darn good wake up call.

I hate to admit it but I have done the same thing The problem mainly caused by programming error as much as setup! If you read the report he used a G97 for the facing operation which accelorates the spindle speed & tool feed as the tool works closer toward center. He was machining 1" dia 303 stainless rod with a bushing in the center of the headstock thinking that the rigidity would never allow what happened. In my case 1" 304 stainless Hex rod with 3 bushings in the headstock & about 12" through unsupported, also programed with a G97. Cycle start, tool rapid to position, start facing work while accumalting RPM's as tool neared center. At about 1200 rpm's harmonic vibration started & I hit the emergency STOP button, as it bent the unsupported material sticking out the back of the machine headstock at high RPM. Be AWARE!of programing the usual G97 feature when working long work.

m4220

M4220, you hit the stop button when it happen. Not take a walk around the lathe to look things over. The red button now!

quote:

Originally posted by dpcd:
The main thing they taught us in trade school, safety wise, was not to leave your chuck key in the chuck. One guy did and broke a window; fortunately not hitting anyone.

I was shocked! The last machine I bought came with KIDDIE-KEYS. Most dangerous things I ever saw. As I was grinding the plungers off on the belt sander, the plastic retainer melted out and the spring popped the plunger out and the sander belt shot it into the floor. If I hadn't been wearing pants and shoes - - - - - - - well, never mind.

What a terrible thing to happen, and so avoidable.

I let friends, and friends of friends, use our Emco lathe for some work they need done.

And the number of individual who come to work on the lathe with very long hair hanging loose, and jewelry loosely worn around their wrests and necks, is incredible.

It really does not take that much thought to be safe in a workshop, or a gun range.

I used a piece of bungee cord to keep the chuck key above the lathe.

My High School machine shop training was stricter than my gunsmith school training of the 1960s.
I wonder what it's like today with the crazy fashions etc.
In Industry we always had to review accidents .All kinds including death. Mostly ignoring safety equipment and safety proceedurs !!!

More than 30 years selling all sorts of lathes to both heavy and light machine industries, bar handling was a critical concern in every application.

Most CNC Screw machines have either a bar loader or a bar feeder. If you have only the occasional long bar, then they could be cut on a band saw or power hack saw. It's up to me shop supervisor to provide guidance to new employees so that this kind of thing doesn't happen. In a bigger shop, process or industrial engineers should draw up detailed process charts so that an appropriate material configuration could be given to a machine operator with cutting tools.

I can hear the people saying well were not that big or the operators should know that. My question then is how many people can you afford to lose?

Of course, if you cut the bars, you are going to lose a few inches of stock every time you go to a new one. Here again at what price economy.

You may note here that I have not recommended purchasing a bar feeder for that machine.

3 or 4 times a year I would get a job with about 20 1 7/8" shafts up to 18' long. I bored a wood bearing and fastened it to the roll cage on my forklift. Positioned the forklift to hold the shaft straight. Kept the cutting speed low. Worked good. Poor people got poor ways.

Dave

Terrible accident, but shit does happen.
I machine a ton of down hole prongs. Usually
1/2" by 6' 4140. Bushing at the far end of headstock and G50 at 1200rpm and no problems.
Someone needed a seven footer like right now. The helicopter was waiting while company man was hopping around like he had to pee.
Forget to set G50 @ 1200.
Scared the crap out the company man. I had a five gallon bucket to catch excess coolant. Never could find the handle from the bucket till about a year later a friend of mine looked up and said what's that. It pierced the metal roof.
A buddy of mine lost an arm polishing a shaft with gloves on.
A machinest at Cameron had his calf fillet off by a shaving while up on top of a big Bullard.
An other young kid at Drill String fell into a big CNC and
was wrapped up.
Can't stop a machine. It has no brain. Got to keep your brain engaged all the time.

I've worked quite a bit in an industrial machine shop and have seen a few wrecks and had a couple myself. Twice, I had the tailstock back off. Once it was while machining a 2" hydraulic rod about 3 feet long. I figure some chips on the tailstock clamp plate kept it from holding as it should have and the lever fell down and the tailstock moved. That rod flew out and hit the floor next to my left foot. Could just as well have crushed my skull.
Another time I was turning a 12 inch shaft, 6 feet long, in a big CNC lathe. In the course of turning the shaft, chips built up between the carriage and tailstock. When the turning was complete the carriage went back to it's rest position which was three inches closer to the tailstock. There was enough debris to bump the tailstock back about a half inch and that allowed the shaft to come out, climb over the toolpost and fall down against the door. If the door had not held up enough to keep it in, I would have been flattened by a half ton of steel.
Had one guy whose coveralls got caught by the leadscrew and he was lucky the lathe wasn't turning too fast and he was able to stop it. He was getting sqeezed pretty good and the coveralls had to be cut off.
Cutting apart hydraulic cylinders was often a calamity waiting to happen but though there were some scary moments, no body was ever seriously injured; just scared!
Ultimately, as with most industrial accidents, it is complacency which is the prime factor in machine shop accidents.
nopride2, I have also used the "forklift as a guard" technique. Regards, Bill.

An other thing that gets people is
if your steady rest isn't set up right
there isn't a cheater pipe long enough that
you can use to tighten your jaws with
that will keep the part from walking out
of the chuck.

And here is one of ours, luckily, no one got hurt.

Walter is a bit accident prone - to put it mildly.

He shot himself with a shotgun, but that is another story!

We got a CNC lathe we use to make our Walterhog bullets on.

I made sure he never touches the machine, but, as you can see, Walter WILL find a way of screwing things up.

The machine has a glass door, through which one can see what is going on inside.

The front of the machine where this door is on a sort of slight incline, to make it easier to work with.

To the right of that door is the keyboard where all the machine switches and buttons are.

Walter gets himself a cup of coffee, and stands in front of the machine totally fascinated of how it works.

He lifts the cup to his mouth, and in doing so his elbow touches a switch on the keyboard, changing the operation.

The machine carries on, and the rotating chuck hits the collet, smashing it in the process.

Several thousands Euros in damage, but no one hurt!

My instructor yelled at me when I wanted to use a box-end wrench to tighten the top nut on our Bridgeport mill.
Said only use open-end wrench so that it can't be left in place.

I have never done it, but I have seen it done several times where a box end wrench is left on the spindle of a knee mill. When it's turned on it makes a "CLACK" when it hits the motor and the draw rod unscrews. Or if it's in reverse it simply twists off the draw rod. Not so very exciting. I personally left a box end wrench on a Cincinnati once. I ran the mill for almost 1/2 a day and had to make a cutter change. I looked for that damned wrench for 10 or 15 minutes before I looked up and there it was, sitting up there smiling at me. It seemed quite happy up there but I made a point of taking it off from that point forward so no one caught me and and gave me shit.

That whole open end/box end wrench thing always puzzled me. I actually got to be the first student on a new Bridgeport many years ago. The drawbar wrench was kind of a combination socket wrench with a brass hammer head on the other end. I was careful but I know of other students that left it on. I use an open end wrench on mine but never understood why the original wrench was designed as it was. Later, as an instructor, one of the projects I had for the students was a drawbar wrench. It was open end with the brass hammer head on the other end. Just seemed safe.

quote:

Originally posted by speerchucker30x378:
I have never done it, but I have seen it done several times where a box end wrench is left on the spindle of a knee mill. When it's turned on it makes a "CLACK" when it hits the motor and the draw rod unscrews. Or if it's in reverse it simply twists off the draw rod. Not so very exciting. I personally left a box end wrench on a Cincinnati once. I ran the mill for almost 1/2 a day and had to make a cutter change. I looked for that damned wrench for 10 or 15 minutes before I looked up and there it was, sitting up there smiling at me. It seemed quite happy up there but I made a point of taking it off from that point forward so no one caught me and and gave me shit.

Yeah, I ran my mill for several seconds with a racheting box end on the drawbar until I figured out what that noise was! Regards, Bill