Close one at work the other day....

[Thad Swarfburn III]

We had an accident the other day at work, and even though most of you won't be exposed to the magnitude of danger that was here, it does have a valuable lesson in it for us.

George has been turning since before I was born, and I have gray hairs. He was on his usual machine, a 31"x120" Dainichi DL75 (one of our smaller lathes...). He was running a CNC job, short pins for a submarine lift project we're making for the Australian Navy (Australia has a sub? Australia has a NAVY?). He had been working with three foot lengths of stock - 60mm high-ten steel - and running at max rpm of 900. The rest of the stock wasn't cut to length, so he chucked an eight foot piece, I guess with intentions of manually over-riding the speed to a more appropriate speed. He neglected to do this, and shortly after hitting the start button, things got real interesting real quick. The bar bent at the rear chuck and went on an arc of destruction. There was a six foot long, four foot high safety barrier constructed of 2" pipe at the rear of the machine, dyna-bolted to the floor. This was to keep anyone from standing near the rear of the machine. This was INSTANTLY removed from the floor, virtually all welds/threads broken, and pieces of it hurled several metres. Two pieces were lodged in the partition behind the lathe (you can only see the lower one in the pics), one was thrown across the walkway in front of the lathe, and one landed inches from where George was standing. The fact that he was not killed or even injured is a major miracle. Anyone walking past could have copped it, too. The electrical cabinet (white box) took a good clout.

The lesson from this is don't hang stuff out the back of the lathe unless you absolutely have to. And if you do, drop the speed before chucking, and use a roller stand. Incredibly, we don't have one in the shop. Even a 1/8" piece of steel can do you some major damage. Keep your wits about you!

It should also be noted that this is a great way to get the entire workforce assembled in one place in a hurry. Staff were coming down from upstairs! Yelling "free beer and boobies!" wouldn't have worked as well.

Keep your hobby safe. If you're tired, stressed, or sick, take it real slow or go read a book (or HMEM!).
Matt
Apprentice and shop safety rep.

 

[vlmarshall]

As soon as I read "three-foot lengths of stock", I knew where this story was going.

I'm glad everyone is unhurt. Lots of energy in that swinging arc. Thanks for sharing the photos.


Oh, yeah... is the lathe ok? I've heard of headstocks torn loose like that.

 

[kustomkb]

That's one of your smaller lathes?

I've seen the same thing happen with nobody hurt, The operator crapped his pants and froze, never hitting the stop.

The machine didn't stop until the entire spindle disintegrated. I was upstairs writing a test and thought some one was on a shotgun murder spree. Heavy duty work benches were demolished and sent flying like your cage.

Glad nobody was hurt in both these cases.

 

[ChooChooMike]

I'll bet he'll be investing in some new undershorts after THAT one !!

 

[bearcar1]

"So, other than that Mrs. Lincoln, what did you think of the play?"...............

Gees, a true miracle that no one did get killed in that situation. Just imagine being the person walking past that cage as it was destroyed. Talk about a 'brown out'. Danger is ever present in out hobby (and at work) and we all must take nothing for granted to ensure the safety of others and ourselves. Crickeys, that just gives me the willies thinking about that event.


BC1
Jim

 

[mklotz]

It's worth noting that, scary as this mishap was, you shouldn't be lulled by the fact that it was a big lathe and a big piece of stock.

While it won't tear out any stanchions or wall supports, an overlong piece of 3/16 or 1/4 stock in a small lathe certainly has the potential to break bones and do some other really serious damage to your anatomy.

Check the speed setting and power feed(s) engagements on any equipment before throwing the switch. Surprises are nice for birthdays but really suck when it comes to machinery.

 

[rake60]

I'm glad to hear there were no injuries!
Good example of why it is so important to support the stock.

We run jobs at my place of employment in the CNC's that have
up to 6 feet of stock protruding out the back of the machine.
We use an external steady rest to support the end of that stock.

In my home hobby shop I mounted my X2 mini mill in a position
directly behind my 9 X 20 lathe. That allows for a steady rest to
be bolted to the mill table for support of any long stock that extends
through the chuck and out of the back of the machine.

Rick

 

[Thad Swarfburn III]

Oh, yeah... is the lathe ok? I've heard of headstocks torn loose like that.

Lathe seems OK (see below), it's a tough old bird.

YIKES!! Did he get fired after this incident ?

It's VERY difficult to fire people here (New Zealand), and even if they could, they probably wouldn't. He's one of our better guys, and had a bad day.

A couple of things disturbed me about the events.

1) The scene was altered before the investigation was complete (stock was removed from lathe).
2) The lathe was restarted later that day without having a qualified electrician examine the radically altered cabinet.
3) The operator had a cuppa, then went on to not only finish his day, but do two hours of OT as well.

I'll be voicing my concerns over these, but I wasn't asked to do the investigation, despite being the H+S officer for the department.

Hmm.

Be safe!
Matt

 

[bearcar1]

You have three very valid points of concern Matt. They ALL should be addressed and documented. Any number of events could have stemmed from such oversights. The continued safety of the entire shop will be at risk unless the issues are resolved, or new guidelines are put into place. Best of luck.

BC1
Jim

 

[Tin Falcon]

It's worth noting that, scary as this mishap was, you shouldn't be lulled by the fact that it was a big lathe and a big piece of stock.

While it won't tear out any stanchions or wall supports, an overlong piece of 3/16 or 1/4 stock in a small lathe certainly has the potential to break bones and do some other really serious damage to your anatomy.

Check the speed setting and power feed(s) engagements on any equipment before throwing the switch. Surprises are nice for birthdays but really suck when it comes to machinery.

Marv I can shamefully confirm that statement. I had IIRC about a 1 ft long piece of stock in my little 7 x 10 mini lathe. Turning was OK but I cranked up the speed for either filing or polishing forgetting about the long piece sticking out. and thinks started to happen I was not hurt but I put a big gouge in my 1942 vintage Oak Union Tool Chest OUCH that hurt.
Tin

 

[websterz]

Marv I can shamefully confirm that statement. I had IIRC about a 1 ft long piece of stock in my little 7 x 10 mini lathe. Turning was OK but I cranked up the speed for either filing or polishing forgetting about the long piece sticking out. and thinks started to happen I was not hurt but I put a big gouge in my 1942 vintage Oak Union Tool Chest OUCH that hurt.
Tin

At least the scar on the tool chest will server as a reminder with no blood having been spilled. Better a scar in THAT chest than in your's.