Can Face Shield Stop Exploding 9'' Grinding Disc? Work Safety Experiment 

Exactly my thoughts. A normal grinder would never spin fast enough even if your disk did explode on a normal grinder it would not damage near as much as this video shows. 5X less speed therefor force.

@@isaacodegard740 2x speed means 4x energy

There was a really good annotation on the video though, referring to the fact that the biggest issue is people using this big disks on small grinders without a shield. The small grinders spin faster than big grinders, because they're calibrated to have the same velocity at the circumference of the disk, but with a smaller disk. He measured that they tended to explode at around the same RPM that small grinders spin, so the danger is very, very high

I'm sure they could build a rig that pushes steel against the grinding/cutting disk using springs. Just leave it running until the disk wears down enough to fracture.

@@station240 You wouldn't even need to do that, just clamp it in a bench vise too tight, or else clamp it and hit it with a soft mallet a few times, enough to crack, but not enough to bust it in two.

It flies like that's what it was made for

Sl4yerkid thank god you put this in the comments or someone could’ve gotten hurt

Sl4yerkid i'm pretty sure the part where they attached a grinding wheel to a 30krpm router showed how important it was to stand far away but ok lol.

@@totalcontrol2025 I know you're being sarcastic, but I fail to see what you're trying to say. Obviously my comment has no effect on the past..

Yeah that thing skipped off the ground and just kept on a-going.

Great idea!

@@garywheeler7039 Thanks :-)

Or more descriptively, the "" keys.

Thanks for that!

Yay!!! Finally learned how to do it!

He, it dies with the comfortable feeling that no other watermelon was killed with that piece of shrapnel! xD

It does !! It catches the disc fragment INSIDE your head !!

@@thetorchchannel357 Exactly what I want to happen in this kind of situation!

Yep it really failed.

The helmet, it does nothing!

There needs to be a R rated remake

I think in the 2nd one, he was stuck in a home that was being renovated and had lots of tools. Also, didn't he use a tool chest to chase them down the stairs? (One wonders how he got a 150+ pound chest with hundreds of pounds of tools up to the second floor alone....)

@@Sky-qd2mf oh but there is a R rated version ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ZgLqxSPIhR0.html

honestly in the two movies they made for that series (the first and Lost in New York) most of his antics would have looked like Saw if the movies were not meant to be family angled with Loony Tunes style injuries. I do not remember where it was posted but a trauma surgeon did once go over Home Alone and the results were pretty much Saw.

@@filanfyretracker yeah, that's what I mean. You don't need to make Kevin a psychopath, just let the injuries be real.

Yes! Seems like this normal safety gear does not offer much protection. Would be interesting if those helmets would actually work. I could also think of bullet proof vest, how many layers of paper and - once the lake is frozen, how much ice you need to stop the disk.

@@stoffls ice is strong!

and purple helmet

I should have a British army composite helmet somewhere for Lauri and Anni.

Actually I like the idea of testing all sorts of various safety gear in these types of situations just to see how well they help even beyond their rating.

I know right? When he said to make suggestions for what to do next, the first thing that popped into my head was pretty much exactly what they showed in the teaser.

On Sunday's Twitch stream, discussions about what other items could be launched from that new air cannon barrel. PIZZA was the #1 answer. Like those stereotypical small, cheap, frozen ones. Lauri seemed to really like that idea.😊🍕🍕🍕

This is exactly what I wanted👍

Lmao

Good idea. :D

And never ever remove it again

Don Johnson Yeah good idea.. I had a 5 inch disc explode and despite the guard I still ended up with a dozen stitches in my upper leg. Hate to think what it would have been like without the guard.

@@jimmyj2563 I had a nine inch cutting disc kick back, still don't know how it happened but it cut the back of my hand to the bone and severed two tendons, about six months in plaster and physiotherapy to get the use of my hand back and a six inch scar, I was lucky as I have the use of my hand back, and yes the guard was fitted, nine inch grinders are now just for that.

Exactly, and put the chronos so we see a top view looking down. The chronos videos in the lab were really cool, one videos looked like blue fire or something like that, I love these videos!

Yeah like you don’t wear sleeves and you have to pull wires out of your arms all day and if you do wear sleeves you run the risk of it getting caught and fucking up your arm

They stick in eyes particularly nicely, I knew an idiot who thought his reading glasses were adequate PPE

Netyr my father?

I left a comment elsewhere before I saw this one. I've had a wire brush wheel catastrophically come apart on me before. Had wires stuck all over my arms and torso. Even had 3 wires pin my sack to my thigh

It would just fly over the shield...

@Mr T @10x the operating speed it wont be just twisted/distorted, it'll be torn apart. now, hopefully it'll have absorbed some of that lethal energy.

That is actually the situation which shield meant for. Distance between shield and disk is really close, so it shouldn't be dangerous. I mean exploded disk will not be able gain its lethal perspective, shield will absorb most of the disk fragments and even could not get any damage(bending or etc) . So probably fragments will ricochet out of user

on an actual grinder, speaking as the lucky jackass who DIDN'T take the guard off, I got pelted with tiny shrapnel out of the wheel's plane of rotation, but the guard held and was fine. Big bits were redirected away from me (one came almost tragically close to another coworker 20 feet away, but he was missed and was fine after he changed his undies). On this router, the blades are being spun up to 5 times faster than they're designed to, and I'm not sure how you'd go about attaching a guard for testing, but I would surmise the guard would be destroyed (ruined beyond reuse, not shredded) but it would mostly contain and redirect the parts exploding outward. a theoretical user would be safe, but no one else in the area would be.

@@tashkiira7838 my dad got his hand fucked when the grinding wheel exploded

And then goes right under the legs of the camera tripod at the back of the bunker. A near miss for that camera and tripod.

Nice catch. I didn't notice that until you mentioned it.

It really looks like the other way around. Of two grinding discs, both preferentially targeted a watermelon.

Quickest way to cut a watermelon that I've ever seen. 😀

The grinding disk doesn't like water melons, that's why.

Better hide behind the water bottles 😆 not a single scratch 👍

photonic induction!

that is the key to its strength. force absorption

Is that a safety factor of 4.

@@Apjooz that is results in safety factor of 4 since the centrifugal force goes up in square of speed

Beyond the press : Tip for next test, paint a white line on the disc for easier see the rpm in slo mo.

He's 3 for 3; goggles, facemask and helmet.

Think he's using aimbot?

Yeah. I would have expected the safety stuff to do better than it did. It seemed to slice right through without slowing down significantly. I guess I should get a slab of poly-carbonate and make a face shield out of that!

@@ACat1255 I think the problem is that the energy here is too high for any wearable protection. Even if the face shield stops the disk, all that energy gets mechanically transferred to your head and will probably snap your neck.

@@ACat1255 let's be reasonable here. Those wheels are being spun up by a router with a modified chuck Lauri cooked up. in normal use on a grinder they won't get to HALF that speed. Use your guard, use PPE and don't use dodgy wheels.

@@tashkiira7838 "dodgy wheels"... meaning: don't purchase chinaseum wheels from harbor freight. consider yourself warned.

Yep, BTPS (Beond The Polycarbonate Shield) -channel 🙂

Excellent safety warning videos. Don't stop this is "preeetty goood" content

@@midoctor I hope the kinds of people who remove the gaurd and only wear safety glasses with angle grinders will watch this and have a second thoughts. A little bit of convenience or comfort isnt worth the increased risk.

Quick and painless :D

Gearloose well... dunno about painless! 🤣

Soo friggin funny! “ real acid?” - Rainer wolfcastle

Same idea here. Some of them shake like shit. But hard part will be to spin them fast enough. That small electric motor won't do it. Maybe with gearbox of some kind. And that silage pit is also no go for this. Metal pieces from concrete disk will bounce fly in any direction.

@@soundspark yes they do, my thought exactly.

Don't know about the diamond tipped ones but I've seen a composite disc explode from a walk behind saw. My uncle was running it. A piece of the disc nearly the size of my hand shot clean through his calf so fast that he didn't even know it till we informed him that he was bleeding

that would be a wonderful and terrible idea both. First off, those blades are very expensive. Second, they're made of metal, not fused particulate like the grinding disks. That means they weigh almost as much per unit volume, and are less likely to snap. Third, those things are HEAVY compared to even a 9-inch grinding disk, simply because they're over a foot across ('small' ones for masonry saws are 14 inches. if you mean the huge monsters used for street work, those are up to 36 inches) and as such have a lot of material to make them. A home router like Lauri was using won't get those things up to speed without the motor failing--I'd be surprised if it got up to 100rpm. So it's a FUN idea but entirely impractical to try.

you get it as well.Hahahaha! I;m not hiding behind the plywood anymore

...And if a third of the disc weighs about 200 grams, the momentum in 163 m/s would be 32,6 Ns, which is quite equal to direct rifle shot. en.wikipedia.org/wiki/Newton_second

Also, damages/dammit cheese😂

Actually is Lack, but Block could be a better name for it, after this..

@@taurielv it's lack of block :D

@@idvarhurd7804 Yes, just that!

I thought Annie said "Black", ie: IKEA just calls it the colour.

Something like a 10" table saw blade!

@@IceBergGeo That would be fun and if it doesn't explode at 30,000 R.P.M.,build a device that will spin it up to 100,000 R.P.M..HAHA!!.

I was going to suggest that too. I feel it would be very mayhem!

And cut through the neighbors house ? Or the one behind it

@@nz5123 HAHA!!.How about the whole block?.

You could always set up a watermelon decoy in the workshop. Any exploding discs should head straight for it🤣

Just like mobile home parks are tornado magnets! :-)

not really no... if you watch the replays large bits of saw went in all directions

Un frozen ice here in R Kansas is known as METH.

y'all still drink unfrozen ice? where i live we drink condensed humidity

Remove it from the freezer to Un-thaw. So many people say that stupid shit. Even after explaining it they just don't get it.

@@rogermarshall8991 Is that like "hot water heater"....? 🤔🤦🏻‍♂️🤣

No, it would have shattered. Even the first impact tore the bottom loose from the mounting.

The thing with the wood vs polycarbonate is that the wood didn't flex and couldn't absorb the impact, where the plastic did deflect and absorb energy, so it didn't allow it to go through.

At least they spelled it like they said it

It's made of lots of carp.

Polin Karpo-naatilla on asiaa.

"Rue-in-ed"

Kyy-4