lathe safety question

I remember in college being taught on a 4 hp metal lathe and being told by the professional machinist how dangerous these lathes could be. This was very close to the time when a Yale student died in a machine shop 'A TRUE TRAGEDY': Yale student asphyxiated in lathe accident at chemistry lab, medical examiner rules - New Haven Register. As I was told, if you get your hair caught in such a powerful lathe: if your lucky the hair will get pulled out, but that most likely you would get pulled in and that due to the immense power of the lathe you would not be able to provide any resistance.

Right now I have been thinking of purchasing a small cheap bench lathe 3/4 hp and it got me to wondering. Do I have to be as careful with a smaller low-power lathe as with a big one? And if not, at how many horsepowers (3/4 hp, 1 hp, 2hp, etc.) does a lathe become realistically deadly? Surely a 3/4 hp lathe 8"x16" and 3/4 hp could badly injure you, but could it easily kill? Also, I have been thinking of getting a Grizzly 10"x22" 1 hp lathe instead so I would be curious to find out how dangerous such a lathe would be as well. For example, could a 1 hp and/or 3/4 hp lathe pull you in and asphyxiate you if your hair gets caught in it?

likely hair would pull out by the roots, but getting smacked by a chuck jaw might be the death of you, knock out your teeth, bust your bones, ...smack a bone and break it..twist off a finger..on a small lathe..

One horse power..a real horse tied to your hand and pulling with its might is one way to look at the safety/danger of a lathe.

I used to drill with a 1/2 hp drill motor when I was a kid and when it it stuck I had to ride it round until it stopped .. Think I was about 7 -8 maybe 10 or so, and yes did that more than once.

Its not just hp, its also gearing. Any spindle can be dangerous if its running slow enough and the work is small enough. Think riding a mountain bike in easy gear.
Be respectful around any spindle, even a wee one.
Cheers D

djf123 said:

I remember in college being taught on a 4 hp metal lathe and being told by the professional machinist how dangerous these lathes could be. This was very close to the time when a Yale student died in a machine shop 'THE REAL TRAGEDY': Yale student asphyxiated in lathe accident at chemistry lab, medical examiner rules - New Haven Register. As I was told, if you get your hair caught in such a powerful lathe: if your lucky the hair will get pulled out, but that most likely you would get pulled in and that due to the immense power of the lathe you would not be able to provide any resistance.

Right now I have been thinking of purchasing a small cheap bench lathe 3/4 hp and it got me to wondering. Do I have to be as careful with a smaller low-power lathe as with a big one? And if not, at how many horsepowers (3/4 hp, 1 hp, 2hp, etc.) does a lathe become realistically deadly? Surely a 3/4 hp lathe 8"x16" and 3/4 hp could badly injure you, but could it easily kill? Also, I have been thinking of getting a Grizzly 10"x22" 1 hp lathe instead so I would be curious to find out how dangerous such a lathe would be as well. For example, could a 1 hp and/or 3/4 hp lathe pull you in and asphyxiate you if your hair gets caught in it?

Click to expand...

Please read the sticky up top about guidelines.

Your question would be better served here: Home Page - Projects and Articles on Our Forum! | The Hobby-Machinist

I saw a preety gruesome lathe accident not to long ago on a FB machinist page. Let's just say he went in and came out the other side. All lathes and open Mills are dangerous.

No gloves no long sleeves no chains. If it's long and can be sucked in a lathe doesn't care. Neither does a mill. Hell we had a guy In the shop break some of his fingers with a DeWalt not to long ago.

Sent from my SM-G950U using Tapatalk

No matter how big or small the machine, ALWAYS use your brain and take safety precautions.
Tie your hair back, roll up your sleeves, NEVER wear gloves, etc... 3 basic common sense rules. And never take anything for granted.

Here find a safety sheet on lathes but most lath hands will tell there are many more things to be careful of base on experience.

http://ehs.yale.edu/sites/default/files/files/metal-turning-lathe.pdf

guys /gals starting a lathe with not a clue...

Running most any machine is likely the most dangerous thing a person might do.

Even a shitty little bench grinder has enough power to seriously fuck you up. And that's only 1/4 to 1/3 hp.

As far as gloves, watch this YouTube

There is a great deal of information available about the Yale lady who died in that shop. Her hair was caught
in the lead screw of the lathe, and she suffocated when her neck was pulled into the bed of the machine. She
was working alone in the shop at the time.

Researchers were specifically told to not work alone in the shop.

There is both an OSHA investigation online, as well as a private investigation firm report that had been comissioned
by the university.

I think that's a real question, but it falls into the "distinction without a difference" category for someone actually operating a lathe. do you WANT to have a couple of fingers ripped off? 1/2 horse is plenty to do that.

I think a real distinction might be a flat belt vs a gear head unit, but a properly adjusted flat belt will easily transmit enough force to kill, so probably a "loose floppy flat belt" is really what I have in mind.

I'll bet many machinists have started out on an old flat belt South bend that would stall just looking at it, and that saved a lot of tooling and body parts, but basic safe practice is the ONLY thing to really rely on. (and a foot brake maybe).

The Yale accident, what a shame...A lathe even a small one can kill one so fast. In this case might have pulled her head to crash into the machine.

Yale student Michele Dufault dies after her hair 'is caught in a machine' | Daily Mail Online

A couple weeks ago, a popular Youtube channel where a close friend was working in his shop, went to do something real quick on his lathe. He was wearing gloves, got caught and broke facial bones, a busted arm etc. he was alone in his shop, he was able to stop the chuck and hold it until someone came for help several minutes later.
If it was a gear head, it probably would have killed him.
basics go a long way, no gloves, rings-jewelry, tie long hair, no loose clothing, no long sleeves............
These machine tools can kill.

Looks like it's been well covered by now but, always remember if it has a motor electric, pneumatic, gasoline, diesel or Steam it can kill you. I watched a 200lb man brake his arm with a 1 inch drill chucked into a 3/4 hp electric drill.

A long time ago, in an old shop that is now long gone, my mentor told me that a small lathe will bite you, but a big lathe will eat you alive. Regards, Clark

Horsepower really doesn't have much to do with it. Rotating mass has inertia, which takes time to stop. A small lathe make take a few seconds to get up to speed, but can still spin a workpiece faster than you can stop it with your hair, your arm, or your face.

Some may say that I am a bit of a fanatic on it, but I think safety in the shop is way up there in the list of priorities while working.

Long hair? NOPE. I have a haircut that a Marine Core drill sergeant would approve of. Well, almost.

Long sleeve shirt? NOPE. I only own a couple and I never wear them. Frankly, most of my shop time is in my tight fitting undershirt.

Gloves? NEVER. I have a pair around somewhere for lawn work, but I never used them much there either. I have disposable gloves in the shop, but again, rarely use them. And never at any machines. They are for handling things like solvents and other chemicals.

Others have said it in one way or another: it is the torque that is the real factor here. When the HP is geared down, even with pulleys, the torque can be increased to almost any level. Even a small motor with a fractional HP rating can reach dangerous proportions when the speed is reduced with mechanical means. There is no simple cutoff point that the OP is asking for. It simply does not exist.

Oh, and you can not count on pulleys to slip and save you. A properly tensioned pulley is designed to transmit the FULL horsepower. This may not be the case on a machine from Horror Freight, but one that is properly designed and tensioned will be just as deadly as a gear drive.

I think every lathe should be equipped with emergency stop switches at several locations around the machine and/or the bench it is on. I am in the process of wiring such a system on mine, even though it is below 1 HP. I figure I want to be able to reach an E-stop button from any position I may become trapped in. I am not a big fan of OSHA and their tall stack of regulations, but this is one area where they could do some actual good.

After I finish with rewiring the lathe, I intend to look into doing it with the mill too. And the drill presses.

I say to you all, work safe.

When I bought my lathe I had to move it through the gate from the alley. I made sure to wear heavy boots with a safety toe. I ended up dropping a crowbar on my big toe. turns out I had the wrong boots on. they did not have a safety toe. I ended up losing that toenail. It took about 12 months to grow back. The size of the lathe ahd nothing to do with this.
Bil lD

If you are brain dead and run any machine the rest of you will soon follow, if you run machine tools dont be brain dead real easy.....Try running a 72 inch bullard vlt at 200 rpm....Phil

Back when i tried to help kids with science fair projects, mommies would ask "Will he be running dangerous machinery?" My answer was "Damned right it's dangerous. It is made to cut steel. It will take your arm off quicker. This is the most dangerous place he has ever been, act like it."

71 years I have been running these machines and I still have all my fingers, a few nicks, all a long time ago. The advice I give motorcycle riders applies here, too. When you feel you have mastered it and am no longer afraid of it, get off, sell it and never get on one again because you are just meat for the undertaker.

Bill

djf123 said:

Do I have to be as careful with a smaller low-power lathe as with a big one?

Click to expand...

Yes. Always.