Don't get complacent about shop safety

[Tyrone Shoelaces]

I would be tempted to equip such machines with a VFD wired up for estop implemented using DC current passed through the motor windings - one can stop in a few seconds. The DC acts like a field winding, and the motor changes into a crippled generator, and turns its rotational energy into heat.

All radial arm drills in the UK are supposed to have a similar device. It stops the spindle instantly.

Regards Tyrone.

 

[CarbideBob]

All radial arm drills in the UK are supposed to have a similar device. It stops the spindle instantly.

Regards Tyrone.

Instant stop. ??? This is the holy grail of tool engineering.
Stop right now so that we can see the chip formation.
Such is so brutal.

 

[CarbideBob]

Insignificant compared to riding motorbikes....and Im still doing that.

You do realize that these things are just two-wheeled coffins...

 

[Tyrone Shoelaces]

Instant stop. ??? This is the holy grail of tool engineering.
Stop right now so that we can see the chip formation.
Such is so brutal.

Inside half a rev supposedly. I never tried counting. It’s amazingly quick.

Regards Tyrone.

 

[Bill D]

I remember the school paper in Jr. College had a write up about a injured student. He was working at home under his car and the cinder blocks it was on crushed down and pinned him.
He was a auto shop student and said he thought the safety rules about proper jack stands only applied at school if the teacher was watching.
Bill D

 

[Bill D]

You do realize that these things are just two-wheeled coffins...

Some have three wheels.
Bill D

 

[john.k]

Ride fast--die young ......I tried ......came close more than once,but here I am ...old.

 

[JROC]

I don't understand. Isn't this a shop with machine tools and people who know how to use them? I would expect maintenance to remove the worn broken parts and have them either repaired or duplicated by an in-house machinist. Brake linings can be had and usually replacing them isn't an ordeal.

Sometimes. For me to give you an honest answer would be me bad mouthing our maintenance department. Let's just say it's not the best I've seen' and that's an understatement. But use we occasionally make parts to repair machines, presses, etc. Not too long ago I had to make a piece that locks the tail stock on a small HAAS lathe. The stock part broke, was cast steel, and expensive from HAAS so the shop decided to just make it in house out of a piece of A36.

IDK, I've seen the foot braking mechanisms inside a lathe. Is it a band that raps around a pulley with a kill switch? I doubt it uses brake pad materials, but IDK. IMHO it's an excuse, but IDK. Hopefully our new safety guy, who up until a few years ago was one of the best tool makers I've ever worked with, and a close friend who help me during my apprenticeship will push the issue hard. I asked me why I didn't step on the brake, and I told him that it stopped working a while back. He didn't know this and was not too happy to hear that.

 

[WakelessFoil]

I've been subscribed here for a while, but believe that this is my first post.

Almost got taking out this world today. I'm finishing up a die I'm building, and was in a lathe making some stop blocks. It's a big lathe, and I don't use it a lot, but the other lathes were occupied so there was no reason not to use it. I guess one good reason not to use it is the foot brake is broken on it. Anyway being a big lathe the tail stock is big and heavy so you have to put some weight into it to get it to move. I had it spinning at 670 RPM's and just finished facing one end of a stop block, and chucked up on a center drill to spot my thru hole, and put my body into pushing the tail stock toward my part and my Dickie shirt got rapped up in the feed shaft spinning and it started pulling me in. I quickly developed that crazy adrenaline strength and started to pull at my shirt tail, but it was rapping around that shaft real fast. I bent over and stuck my arms straight to let it rip my shirt off me. It started tearing the back of the shirt and ripped out the buttons, but on the way off my sleeve was caught on my right hand. This is where that adrenaline strength really came into play and I just ripped it out tearing the sleeve. My hand is pretty sore, and swollen, and I had a bunch of grease on the top off my hand off of the lead screw, that's how close it was to being pulled into the feed rod.

View attachment 381469

The crazy thing is, is the catalyst for this was a thread (clothing thread) hanging off the bottom of my shirt tail. A little string that they used to sow up the shirt with almost got me killed. After it ripped my shirt off we couldn't get it to pull off the rod. We slowed the lathe down, and put it in reverse, and after the shirt came off the shaft this little thread was perfectly rapped around the shaft about 3-4 times before the shirt even touched the shaft, and it was just strong enough to lift my shirt into the shaft, and let it start rapping it. I think the shaft having a light coat of oil covering it is what caused this lightweight sticking to stick to it, and start rapping around the shaft.

Life's a trip. It's crazy how a little string sticking to an oily rod can about kill you. I've been a tool maker/die builder since March of 04 so almost 19 years. You hear about people getting pulled into machines, but I've spent a lot of time turning parts, and never seen anything like this happen. I don't work in my wedding ring, I keep my hair short, I don't wear jewelry, and now I think I'm going to start tucking my shirt in when I'm running a lathe. It's easy to get too comfortable, and forget how dangerous the machines we use can be. I've got 3 little girls under 3 years old, and that would of been a real gurus scene if I'd gotten pulled into that lathe. That shirt and me pulling on it didn't slow it down one bit. I guess the good Lord decided that it wasn't my time to go.

Stay safe and aware people.

Glad to hear you escaped even if it was only just. I wear a jumpsuit around the shop at all times and it's pretty comfortable and fits well. This is a good reason to get out the cuticle scissors and scan my suit for loose threads.

 

[john.k]

I was sent to a "Safety Update for Oldtimers" course ,as demanded by BP if I was to be allowed back in the refinery........really pissed Col ,cause it cost him $1500 for the course plus having me missing for a week......Anyhoo,I got 100% for the course......Col says "How come you get sent to a course ,yet you know it all".... simple .....every answer to a safety question was the exact opposite of what Col was doing.............for instance ,safety course says before job start ,everyone must have their say as to how it is done .........Col would fire anyone who questioned him.,or made suggestions.....called it ...Arguefying

 

[chipss]

Many years ago in high school metal shop class with the clear memory as if it was yesterday:

I'm toiling away on a South Bend 13" making a useless something that gets graded and the teacher was giving a demo to 4-5 kids on the big drill press. A hefty 480 volt ~3hp all gear drive thing with a multi speed gearbox. For some reason I glanced over and saw the teacher had his tie in the drill bit and it was wrapping up. I sprinted the 20 feet and slammed the shift lever into reverse as his chin was close to the 2 inch drill bit. I knew that hitting the stop button takes forever for the machine to stop and this ain't the time to wait for that. Fortunately he had it in low low and the bit was turning I'll say around 60 rpm.
The sad thing was that the other kids just stood there watching him like dazed idiots. It seemingly took forever to unwind him and he was ok. After that he wore clip on ties.

For the next 50 years I sent and got Christmas cards from him. I'll assume he has passed as the cards stopped coming.

No injuries (knock on my wooden head) on me other than some skin being carved off a finger by a flying chip on my measly South Bend 9 inch three years ago. I also don't wear my wedding ring.

 

[john.k]

I think the most dangerous situation Ive been in was being assigned a meth addict as a helper /observer in elevating platform work......The young guys knew he was crazy dangerous,and thought it was big very funny joke on me.

 

[Knuckle Buster]

A maintenance department in a machine shop and they can't fix a foot brake? Because they can't get parts? They all should be fired!

I was thinking the same thing!

 

[Motogomi]

While visiting a friend at a nearby machine shop that did BIG work (16 foot swing lathes, no guards) I noticed the chips coming off one of the lathes were these long, stringy razor sharp things about .04" thick. One of them could cut you in half! The operator said that the supervisor would only let them use the same ancient inserts with no chipbreaker. I drove back to my shop and got some inserts with chipbreakers (and current technology coatings) and gave the operator a few. The supervisor came by a while later and said "where are the chips?" The operator pointed to about a cubic foot of perfectly curled chips on the floor. And he also told the supervisor that he was running at about twice the speeds and feeds. They finally started using modern tooling after that. Thank God nobody got killed.

 

[gustafson]

Kiss those girls.
All physical work has some element of danger
Glad this is an 'almost' story

 

[john.k]

As Col would say...If you aint near kilt at least once a week ,your aint working fast enough.

 

[dazz]

Hi
I wore an apron until it got caught in the lead screw and started to wind me in.

I was operating a lathe in a training shop back in the 1980's. The work piece started to wobble a bit so I hit stop. Just as the chuck was about to stop spinning, the chuck fell off the spindle onto the lathe bed.
Something similar happened to another trainee operating a lathe at max rpm. I was told the chuck ended up on the floor with enough energy to smash right through an industrial strength roller door.
I try to work at the tail stock end of the work so if something lets loose, I am not in the line of fire.
I have installed e-stop switches at both the head stock and tail stock ends of my lathe.
My VFD is setup so hitting the e-stop applies max power to actively stop the spindle.
If I am doing any grinding or something where I want to protect the precision surfaces, I use news paper, lightly sprayed with oil. I never use fabric. The paper will tear if it gets caught in anything. Grinding dust will stick to the oily paper.

 

[dazz]

All radial arm drills in the UK are supposed to have a similar device. It stops the spindle instantly.

Regards Tyrone.

Hi
I have my VFD setup like that, but I calculated it would still take my lathe up to 16 revolutions to come to a stop, without a workpiece in the chuck. A lot of damage and harm could be done in 16 revolutions.

 

[Tyrone Shoelaces]

Hi
I have my VFD setup like that, but I calculated it would still take my lathe up to 16 revolutions to come to a stop, without a workpiece in the chuck. A lot of damage and harm could be done in 16 revolutions.

The “ Jet-Brake “ set up we had on all the radial arm drills in my last shop would stop the spindle instantly. I’m not an electrician but what I believe happens is that DC current is injected into an AC motor.
It saved the life of a workmate who was using an “ Asquith “ portable radial arm drill in the horizontal mode. He had the spindle running about 3 ft above the ground and he’d reached across the spindle for a coolant bottle. The spindle grabbed him by a loose rule pocket on the leg of his overalls. He was lifted off his feet and spun around until he made contact with the “ Jet-Brake “ probe ( just like a telescopic car aerial ). That stopped the spindle immediately and he was thrown onto the concrete floor.
He had plenty of bumps and grazes and a couple of broken ribs but he lived to fight another day.

Regards Tyrone.

 

[john.k]

Stopping a drill is easy ,if you have a clutch disconnect.........the tricky one is stopping a 20" chuck