There was a shredding scene in one of the Bond films but it was a different type of high speed device. No chance to tap dance on it. Here is the slow but inexorable shredder I mean:
Well, indefinitely, as long as they kept their feet away from the central line where the two rotating parts come together.
That’s a very tough movement though. You’d have to be avoiding the grabber teeth while moving your legs in essentially opposite directions (outside → in) and the space is wide enough that you couldn’t watch both feet at once. I’m betting one foot or the other gets caught pretty quickly, even if you’re a professional tap dancer.
It would take slightly less coordination if you did it like a jumping jack, jumping with both legs moving out at the same time - but that makes it harder to make sure they don’t land in front of a grabber. And that kind of jumping requires a great deal of stamina. Again, just a few minutes.
Keeping your feet wide and just going straight up and down might work if you are tall enough and have really strong hips. Say, a gymnast or speed skater. I reckon a distance skater might last 45 minutes. That’s just off the top of my head though.
I cannot even attempt an answer to the OP’s question, but that is one scary machine!
For the rest of their life.
I thought Vespa drowned; didn’t know she was shredded, too.
Long enough to be able to jump off to the side away from all of the teeth?
Interesting to see all of the propane gas cylinders go through this thing. Of course they need to be emptied and purged with air first. And the way to do that is to screen them out of the waste stream until this important step can be done.
This reminds me of when I did some quarterly inspections at a Construction & Demolition waste recycling facility for a period of time earlier in my career. The facility had a metal shredder just like this, but it was not open to view.
Anyway, about every six months or so an unpurged propane cylinder would apparently slip through and cause an explosion. 
Fortunately the shredder was well-shielded, so nobody was ever hurt. But the blasts did occasionally blow out some windows. (I was asking why the windows near the shredder were filled with plywood instead of glass, and the answer was that they got tired of replacing the glass every six months.)
Anyway, there is no way the machine seen in the OP would be permitted by OSHA here in the U.S. If any of the people poking the items being shredded got their hands (or a bracelet, or whatever) near those teeth, it would drag them right in with horrendous results.
That’s why the shredder at the facility I inspected had a remotely operated, fully enclosed shredder in which a conveyer belt transported the items to be shredded instead of a person poking them with a stick.
(By the way, I was inspecting the C&D waste recycling facility for environmental compliance, not safety.)
That is one scary machine. Who even makes those. That thing has got to weigh tons!
I’ve been creeped out all day by the young lady at the beginning of the video who briefly grabs the handle of the pot to flip it around inches from the shredder teeth.
If her fingers had gotten caught by that handle, it could easily have dragged her into the whole machine.
I hesitate to even post this because it’s so horrific, but something very similar happened with tragic results to a little boy in my town a few years ago who was helping his father put brush through a large wood-chipper. A branch being pulled into the chipper somehow got wrapped around his wrist…
Those things are horrifying. I have seen videos of larger versions where they can put in an entire crushed automobile.
Damn, I wouldn’t want to be the worker who feeds stuff in, even if I had a strict policy of never, ever, ever reaching over to adjust the item.
The video reminds me of that episode of Malcolm in the Middle where Hal and the boys were putting yard waste into a wood chipper, and then, being who they are, ended up throwing everything they could find around the house into it just because it was so cool.
Yeah, what could go wrong there? That’s a horrible tragedy that I doubt that marriage survived. .
Holy shit that thing is terrifying!
Here’s the 14 year old thread discussing this event: I never knew wood chippers were this dangerous.
Yup, that was it. Didn’t realize it had been 14 years…
It traumatized the community.
So I used to work in an unincorporated industrial area surrounded by properties, some of them just empty lots, owned by various rather shady businesses used for various shady, monumentally unsafe business practices. The absolute worst was an industrial drum recycling center that cleaned metal barrel by burning off the residual contents.
But for a couple of years one said mostly empty lot was used to recycle big cement chunks by grinding them up into new aggregate with an industrial cement shredder. It was HUGE - many, many times the size of the OP’s machine. I don’t know how old it was, but it weren’t new and it had a big open top where you could see big chunks of concrete jostling about like icebergs. Every once in awhile it must have gotten jammed and you’d see employees scrambling about on top of said cement icebergs with long wooden poles trying to get things moving while that fucking thing was running and at times while the icebergs were shifting under their feet. We were highly suspicious of the documented nature of the workers and we had zero illusions about the safety precautions of the owner. He used that and another neighboring lot he owned for various money-making schemes over the years, like a similar sawdust making venture ground in the open air that constantly left our facility (and cars, sometimes persons) covered in a layer of that shit blowing across the fence line. Fun times.
Wow, that’s an uplifting thread to read first thing in the morning.
This was particularly frightning:
I have done that same thing many times. (the cutting with a circular saw - not the dying part)
Holy fucking shit! I’d have called OSHA.
We had some trepidations because of the high likelihood that most of the workers were undocumented and we didn’t want to get them in trouble. Plus a heaping tablespoon of the old ‘mind your own business and avoid feuding with the neighbors’ arguments. But ultimately we did one day.
It’s impossible to say if anything came of it. That practice declined or disappeared or we just didn’t see it anymore (it was partially or largely obscured at times, depending where they shifted things). But then this was not a regular business - it was a constant series of short-term hustles and piecework. They might grind cement for four days straight because a load came in, then not grind anything for two months, meanwhile switching to moving loads of dirt around. Or just use the lot to store a bunch of mothballed vehicles, before negotiating a sale to a metal recycler. Or stacking waste trees in a huge pile for a year, before randomly sawdusting them for a month. I suspect it was very hard for random OSHA inspections to ever catch them in the middle of anything, let alone a clear-cut violation. It was very, very sketchy but so fly-by-night that I’m sure they were good at dodging authorities.
Now with the barrel recycler we were on the horn to the local air quality district constantly. When they’re spitting out black fumes, you see guys working on the burner with bandanas tied around their faces and your own throat and nose are burning from a couple of properties away, it generates concern 
. It was insane how difficult it was to catch them in the act as well - they were very cagey and the air quality people didn’t have the resources to just sit on them. They also retaliated, by filing frivolous counter-complaints about our facility. Thankfully they eventually shut down/moved elsewhere and there was much rejoicing.
That’s just the tip of the iceberg - feral dog packs, regular car torchings, building construction techniques that boggled the mind. For a light industrial backwater, it was a happening neighborhood 
.