Molten Ferrocerium Launcher

In this video I build a launcher for molten ferrocerium metal, at the suggestion of Ian Builder (check out his channel here): / @ianbuilder
Thank you very much to all of my Patreon supporters who have contributed to help me create videos like this one. A special thanks to my top Patrons: Enzo Breda Lee, Jon Hartmann, TheBackyardScientist & Eugene Pakhomov! / nighthawkprojects
-Ben

Пікірлер: 706

  • @shotguncleric
    @shotguncleric3 жыл бұрын

    "Many of you know the trick..." Welp my wife's gonna be mad we're about to be out of lighters lol

  • @richbuilds_com

    @richbuilds_com

    3 жыл бұрын

    Just buy a pack of flints of amazon/ebay - they are pennies each :)

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    @@richbuilds_com yup i did that

  • @dsdy1205

    @dsdy1205

    3 жыл бұрын

    It also leaves a nasty residue on the floor, ye've been warned

  • @DJTrainR3k
    @DJTrainR3k3 жыл бұрын

    Looks like it would be a great special effect to simulate a large electrical short!

  • @dimesonhiseyes9134

    @dimesonhiseyes9134

    3 жыл бұрын

    Your not far off to be honest.

  • @davemarm

    @davemarm

    3 жыл бұрын

    Electroboom, are you seeing this?

  • @integza
    @integza3 жыл бұрын

    That's perfectly splendid! Awesome project.

  • @HvV8446

    @HvV8446

    3 жыл бұрын

    Integza does it work with tomatoes too?

  • @integza

    @integza

    3 жыл бұрын

    @@HvV8446 I sure hope it does!

  • @HvV8446

    @HvV8446

    3 жыл бұрын

    @@integza can you try it out? Tomatoes aren't useful for anything else so why not

  • @Yrouel86

    @Yrouel86

    3 жыл бұрын

    Have you been watching The Haunting of Bly Manor by any chance?

  • @integza

    @integza

    3 жыл бұрын

    @@Yrouel86 A man of culture I see !

  • @christhebirb
    @christhebirb3 жыл бұрын

    Kids, remember to put on your Starlite suit before trying this at home.

  • @troyw5832

    @troyw5832

    3 жыл бұрын

    Fire safety for black boxes there that starlight...? Could have stoped 911 too.

  • @TrinitronX

    @TrinitronX

    3 жыл бұрын

    Or at least some eye protection 💥👀💥 😁

  • @EzequielBaltazar

    @EzequielBaltazar

    3 жыл бұрын

    Kmon! It's starlite, its easier to just wear a giant taco and pretend to be clam.

  • @lotsagrapes

    @lotsagrapes

    2 жыл бұрын

    And oobleck hats

  • @kingmasterlord

    @kingmasterlord

    2 жыл бұрын

    @@lotsagrapes they got oobleck skiing beanies

  • @razorbackblood06
    @razorbackblood063 жыл бұрын

    That looks alot like that dragons breath incendiary shotgun shells.

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    i was thinking the same thing after i saw the footage

  • @dimesonhiseyes9134

    @dimesonhiseyes9134

    3 жыл бұрын

    The dragon's breath is magnesium. So it is pretty similar result just different material

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    @@dimesonhiseyes9134 i made magnesium powder and put it in the same cannon and well... it blinded me even through a welding helmet

  • @dimesonhiseyes9134

    @dimesonhiseyes9134

    3 жыл бұрын

    @@ianbuilder yes magnesium burns very white and very hot. Your welding helmet should be dark enough to handle it though. If it's an automatic one sometimes certain conditions like daylight can trick some helmets into not going dark. Or sometimes super bright but quick flashes will cause it not to darken. If you are using a permanently dark helmet you should probably be using a 9 filter at least.

  • @carpenoctem3257

    @carpenoctem3257

    3 жыл бұрын

    @@ianbuilder any lasting damage or just seeing spots for like an hour?

  • @KubinWielki
    @KubinWielki3 жыл бұрын

    > This video released 2h ago at the moment of writing. > Ian Builder has reportedly had a bit under 1k subscribers. > He has 2k at the moment of writing. Doubled in 2h, and will very likely rise. That's what I like to see from big youtube channels - proper credit and shoutout where they are due.

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    this man has the statistics👌

  • @intothecalm420

    @intothecalm420

    3 жыл бұрын

    4.5k when I subbed.

  • @PWN_Nation

    @PWN_Nation

    2 жыл бұрын

    7,370 on 12/29/21

  • @caterpillar6298

    @caterpillar6298

    2 жыл бұрын

    Now 8k

  • @willeveryday

    @willeveryday

    2 жыл бұрын

    I wonder how many subs Matthew Wilton got for the ruby video?

  • @zacharypeterson5540
    @zacharypeterson55403 жыл бұрын

    Making this for my gender reveal party in a dry field, wish me luck!

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    lmao

  • @Commodore1236

    @Commodore1236

    3 жыл бұрын

    Better do it in the woods.. California or Australia sound perfect 😂

  • @cseblivestreaming8073

    @cseblivestreaming8073

    3 жыл бұрын

    Oh i was just thinking to give these to the cops instead of lessthanlethal 40mm and shotguns

  • @gaminggonewrong1624

    @gaminggonewrong1624

    3 жыл бұрын

    May the force be with you 🌚

  • @dimesonhiseyes9134

    @dimesonhiseyes9134

    3 жыл бұрын

    Be sure to also keep your gasoline near by

  • @kdawg3484
    @kdawg34843 жыл бұрын

    Sparks at dusk. Just like many of your old videos. The peaceful beauty of videos like this is one of the reasons I fell in love with this channel.

  • @Nighthawkinlight

    @Nighthawkinlight

    3 жыл бұрын

    That's what my wife said, that this was like my old videos.

  • @JyrzStreams
    @JyrzStreams3 жыл бұрын

    As a Californian, this makes me very anxious to watch.

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    oh boy.....

  • @Ecrfour

    @Ecrfour

    3 жыл бұрын

    @Jacob Howell your*

  • @TECHnoman753

    @TECHnoman753

    3 жыл бұрын

    XD

  • @DirtyRobot

    @DirtyRobot

    3 жыл бұрын

    Perhaps you need to reduce the amount of SOY in your diet and then learn how to manage the forests your state gave to the snails to caretake. Snails can't manage forests. Vote your idiots out.

  • @TrinitronX

    @TrinitronX

    3 жыл бұрын

    @Jacob Howell Yes, because doing that for 19 million acres is feasible. 🙄 😆

  • @tonyrider3
    @tonyrider33 жыл бұрын

    The pyromaniac that lives deep inside me loves this, a bar trick on the next level!

  • @GuillotinedChemistry
    @GuillotinedChemistry Жыл бұрын

    Ha ha! I was researching strikers and lo and behold it led me to a NightHawkinLight video! Don't know how I missed this one... this is a real treat. Hat off to Ian for the idea and Ben for the upgraded realization. Thanks for the fantastic distraction!

  • @AgentWest
    @AgentWest3 жыл бұрын

    My first thought would have been to swage out the tube to match the rods so the sanding/machining is only done once. Make a pointy steel rod of proper size, oil it up, and press into the end of the tube. Also this cannon combined with the propane pop gun from a while back (one with clear spiral tube that fire travels through) ought to make for an interesting reusable firework of sorts!

  • @miraclo3
    @miraclo33 жыл бұрын

    I’ve been wanting to build one of these since I was like 10 years old. I’ve also been watching since your original pyrotechnic days. Keep up the great work man.

  • @GrowingAnswers
    @GrowingAnswers3 жыл бұрын

    I can imagine someone walking up with that asking if you need help starting a campfire.

  • @-hastatus-
    @-hastatus-2 жыл бұрын

    Although my English is not as good as I would like it to be, I understand everything you say as if you were a teacher. You speak slowly and clearly. 😀👍 You are one of the first youtubers I follow.

  • @among-us-99999
    @among-us-999993 жыл бұрын

    As soon as I saw "ferrocerium" and "launcher" in the title I knew that this was going to be cool

  • @dawsoncombs812
    @dawsoncombs8123 жыл бұрын

    I made this for my friends birthday, used it to ignite a bonfire that was absolutely huge and the presentation impressed everyone. Thank you so much for the idea.

  • @fizzyplazmuh9024
    @fizzyplazmuh90242 жыл бұрын

    You seem so pleasant and mild and yet you consistently amaze and do the most intriguing things. You come across like a shade tree mechanic but have a brilliant and driven mind. Total admiration.

  • @izzieb
    @izzieb3 жыл бұрын

    Castro explains how he intends to deter CIA-backed exiles at the Bay of Pigs (April 1961, colourised)

  • @ChromaMatrix
    @ChromaMatrix3 жыл бұрын

    Easily one of my favorite things that you've done on this channel. Absolutely beautiful, just stunning!

  • @SushiKing123NorskGaming
    @SushiKing123NorskGaming3 жыл бұрын

    Another awsome video, Ben! I've been watching your videos for years, and I just want thank you for making them. Always fun to watch and learn.

  • @2.7petabytes
    @2.7petabytes3 жыл бұрын

    You never cease to amaze me with the quality of your videos and the inventiveness you possess! Much enjoyed!!

  • @em9565
    @em95653 жыл бұрын

    That intro was absolutely perfect : )

  • @captainkenno
    @captainkenno3 жыл бұрын

    Awesome little project, thanks for sharing! 👍

  • @joshuabry1281
    @joshuabry12813 жыл бұрын

    Yo wear some safety sheilds bro that stuff is wicked, I threw a piece on the ground when i was about 15 and it went between my toes leaving 3rd degree burns.

  • @Mitchell_is_smart._You2bs_dumb

    @Mitchell_is_smart._You2bs_dumb

    3 жыл бұрын

    I'm gonna call shenanigans on that

  • @Ledcke
    @Ledcke3 жыл бұрын

    Ten Minute Bible Hour shout out! Your hat immediately caught my eye. Thanks for being a great channel and supporting other great creators. 👍

  • @jogandsp
    @jogandsp3 жыл бұрын

    Great video as always! Good on you for helping support smaller channels and young innovators! Also... I love the ring, man.

  • @lav6978
    @lav69782 жыл бұрын

    crazy how high quality this video is and its just now that the KZread Algo is recommending it to me, even though I used to watch his videos back then

  • @blitzkreg335
    @blitzkreg3353 жыл бұрын

    Sparks are always so mesmerising to look at. They're always so pretty.

  • @ambrosekillpack4841
    @ambrosekillpack48413 жыл бұрын

    YES, FINALLY, someone who knows the difference between flint and ferrocerium. Flint is a type of quartz by the way, and both flint and quartz are allotropes of silicon. While ferrocerium is an alloy of magnesium, iron, neodymium, lanthanum, cerium, and praseodymium. I'm just thrilled to see someone else who knows and acknowledges the difference between these two materials beside me.

  • @buckaroundandfindout
    @buckaroundandfindout2 жыл бұрын

    Just so many great projects.

  • @trevader2562
    @trevader25623 жыл бұрын

    Absolutely awesome project, and beautiful camera shots there! One note, perhaps it's not the greatest idea to be firing this over all those pine needles, I know first hand how much those like to catch fire XD keep it up!

  • @gordonfischer8484
    @gordonfischer84843 жыл бұрын

    Very interesting video. Ferro cerium is such a cool material, recently I made ferrocerium tipped arrows, a bit of setup work but when they impact a target they make a huge explosion of sparks.

  • @whynotdean8966
    @whynotdean89663 жыл бұрын

    What did you do to piss off the algorithm? This kind of video is EXACTLY what should get 1m+ views.

  • @grimsladeleviathan3958
    @grimsladeleviathan39582 жыл бұрын

    Imagine a kinda monster survival FPS game, and this is one of the weapons you can use to deter a big monster from coming for you

  • @clayq220
    @clayq2203 жыл бұрын

    I love Ian builder. Yes spread the love!

  • @sebbes333
    @sebbes3333 жыл бұрын

    *@NightHawkInLight* 1:49 Thank you! I probably would never have found & subscribed to Ian's channel without you. :D

  • @zaidhussain5206
    @zaidhussain52063 жыл бұрын

    Thank you for making this video it was very informative to me .

  • @danielmiller2886
    @danielmiller28863 жыл бұрын

    Great content and video as always.

  • @BobRoss-bp2yv
    @BobRoss-bp2yv3 жыл бұрын

    thanks for making these videos.

  • @fernandosalgado9114
    @fernandosalgado91143 жыл бұрын

    Ur videos are the best, thanks, greetings from Spain

  • @bugjuicechugga
    @bugjuicechugga3 жыл бұрын

    it literally feels like you never have a even close to un-interesting video. all your stuff is great man

  • @DragonBuilds
    @DragonBuilds3 жыл бұрын

    This is a really cool build. Shooting sparks does look awesome. However, PVC pipe is not made for compressed air and can explode. A steel tank is much safer.

  • @NSEasternShoreChemist
    @NSEasternShoreChemist3 жыл бұрын

    Fire? Flamethrowers? Burning metal? Oh HELL YES! Liked before even watching.

  • @grexursorum6006
    @grexursorum60063 жыл бұрын

    ❤️ very nice video. I guess the sparks are a bit to bright for a nice closeup on the nozzle but I bet it would look amazing. Wonder about the campfire lighting capabilities of the device. And yes (to everyone how want to outsmart me) I know that the torch it self would be better way off doing so. Thanks again!

  • @lewismassie
    @lewismassie3 жыл бұрын

    Man, Ben always manages to find the most interesting things to make videos about

  • @reothomas7624
    @reothomas76243 жыл бұрын

    Came from daily dose of Internet love the content I've subbed

  • @bemusedindian8571
    @bemusedindian85713 жыл бұрын

    Most excellent video.

  • @AussieRossco
    @AussieRossco3 жыл бұрын

    I USED to do the lighter spring trick and flick it for a similar small scale effect. It got stuck down the side of my fingernail, took the fun right outa it! Respect this stuff, it is rather bitey when burning.

  • @elijahcoatney2268
    @elijahcoatney22683 жыл бұрын

    Perfect project for the modern rogue

  • @DM9_eyo
    @DM9_eyo3 жыл бұрын

    Literally looks like a gun you would fine in Fallout 4. Awesome!

  • @schelsullivan
    @schelsullivan3 жыл бұрын

    Brilliant. I'm sure ian's channel is about to blow up. Subbed and belled.

  • @evildead1791
    @evildead17913 жыл бұрын

    Thats awesome, good stuff man

  • @rustamgani6826
    @rustamgani68263 жыл бұрын

    Always nice see You! Thanks! Long time don't see You'r bird.

  • @maryfawber9236
    @maryfawber92363 жыл бұрын

    Thanks . You are so incredible....👍

  • @flitchi.
    @flitchi.3 жыл бұрын

    Great Idea !

  • @charlesreed8420
    @charlesreed84203 жыл бұрын

    great video so far!

  • @MuhammadDaudkhanTV100
    @MuhammadDaudkhanTV1003 жыл бұрын

    Fantastical idea

  • @jaidheersirigineedi8110
    @jaidheersirigineedi81103 жыл бұрын

    WoooooooW. Great video!!

  • @luissantiago5163
    @luissantiago51633 жыл бұрын

    Man that's really neato. Great work!

  • @bensamule3252
    @bensamule32522 жыл бұрын

    you are my new favirote youtuber i found you 15 minutes ago and your videos are so cool

  • @ComradePhoenix
    @ComradePhoenix3 жыл бұрын

    [*The Modern Rogue would like to know your location*]

  • @NickFrom1228
    @NickFrom12283 жыл бұрын

    Since you have a decent capacitor bank, it would be cool to see you demonstrate the principle behind a rail gun.

  • @kellyf3160
    @kellyf31603 жыл бұрын

    Gotta get the Slow Mo Guys to make an upscaled version of this. Awesome!

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    yoo great idea

  • @davidboston7943
    @davidboston79433 жыл бұрын

    Really awesome video, quite the pyrotechnic display! I do have to second some of the safety notes other people have had. Considering this was released just after a horrendous wildfire season (with many fires started by people being careless), please, please people: be careful when you use things that shoot off sparks! The other thing I'd note is that it's probably a good idea to have a pressure safety valve on the air tank. The gauge is great and all, but you really don't want to have a pvc pressure vessel become over-pressurized and explode on you.

  • @keeianfazilkee8552
    @keeianfazilkee85522 жыл бұрын

    Spectacular

  • @pblm6772
    @pblm67723 жыл бұрын

    Now this looks cool

  • @kentborges5114
    @kentborges51142 жыл бұрын

    REALLY DIG THIS PROJECT ! MAY BUILD ONE FOR NEW YEARS 2022

  • @brunokerbaul3826
    @brunokerbaul38263 жыл бұрын

    The best item for a pin-up job coming out of a big cake :-) Happy birthday mister inventor Pou Pou... Pidou Ouaw!

  • @robertwoods3701
    @robertwoods37013 жыл бұрын

    Thank you. I understand.

  • @MetalSkyHigh
    @MetalSkyHigh3 жыл бұрын

    Awesome man!

  • @forestlampcraft472
    @forestlampcraft4723 жыл бұрын

    Cool

  • @basicguy99
    @basicguy993 жыл бұрын

    Nice TMBH hat, great show.

  • @Flederratte
    @Flederratte3 жыл бұрын

    3:35 looks really cool!

  • @Lucius_Chiaraviglio
    @Lucius_Chiaraviglio3 жыл бұрын

    Really should be using safety goggles when doing this. And make sure the grass is wet . . . .

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    if its green grass its safe

  • @Lucius_Chiaraviglio

    @Lucius_Chiaraviglio

    3 жыл бұрын

    @@ianbuilder That might be generally correct, but I wouldn't want to take that chance when large quantities of burning molten metal are the ignition source.

  • @ramennight

    @ramennight

    3 жыл бұрын

    The grass seemed fine. Im not just some rando city boy as well. I live in Montana, we get smoked out in our valley nearly every year from fires and often have one in the valley itself. People are just overly paranoid about fires this year do to the west coast being so on fire, its burning areas people care about. They dont care about "back hills Montana".

  • @ianbuilder

    @ianbuilder

    3 жыл бұрын

    @@ramennight yea fire isnt that dangerous it becomes dangerous when you are scared of it

  • @thetruthexperiment

    @thetruthexperiment

    3 жыл бұрын

    I knew I’d find safety glasses guy! Boo.

  • @agnosjr
    @agnosjr3 жыл бұрын

    Awesome, Cheers!!

  • @RealWunderBanana
    @RealWunderBanana3 жыл бұрын

    That’s amazing

  • @jackquinn4994
    @jackquinn49943 жыл бұрын

    That is so cool! You should totally do a hacksmith style test video to accompany the build.

  • @oddjobbob8742
    @oddjobbob87422 жыл бұрын

    Great fun!

  • @mister-robo
    @mister-robo3 жыл бұрын

    You are my idol! I also like to shoot videos about my homemade products. Thank you very much! Cool video! 👍👍👍

  • @Isaac-47517
    @Isaac-475173 ай бұрын

    Pretty neat. TY.

  • @ZENMASTERME1
    @ZENMASTERME13 жыл бұрын

    This is a perfect excuse to play with fire 🔥

  • @asvarien
    @asvarien3 жыл бұрын

    YAAAYYY!! I can finally live my roleplay fantasy as Jubilee!!

  • @tangopapajuliet9469
    @tangopapajuliet94692 жыл бұрын

    Lots of potential with this effect for photography. Like spinning burning steel wool with wire making a huge circle of sparks.

  • @yurigouveawagner9432
    @yurigouveawagner94323 жыл бұрын

    amazing video!

  • @abhishekmathur9676
    @abhishekmathur96763 жыл бұрын

    Super good

  • @AlChemicalLife
    @AlChemicalLife3 жыл бұрын

    Honestly would like to see this done with some fine Ti. The spark should be cooler and safer than FeCe. Another idea i got from this video was to make a Homemade Cold Spark machine. not 100% sure how it would be done but it would be cool ! That and a Flame projector would be also pretty sweet !

  • @gabehodges1088
    @gabehodges10883 жыл бұрын

    No eyepro. You're a savage my man!

  • @1rez378
    @1rez3783 жыл бұрын

    3:33 when you appy some Gold Pine Resin

  • @qingdom
    @qingdom3 жыл бұрын

    Does anyone know the music artist and song title in this one? Thank you.

  • @danhyatt2206
    @danhyatt22062 жыл бұрын

    Here's another idea, and a question... First, when heating a piece of ferrocerium, as soon as it starts glowing you can take away the heat source and it will continue to get brighter and brighter ( the question is HOW/WHY??? ) and as it gets brighter it becomes more unstable and the slightest disturbance will set it off. When trying to launch a piece with a slingshot the rapid acceleration and/or the air friction sets it off. The idea is to heat it just to the point where it will continue getting brighter without the heat source and launch it while it's still stable enough to do so without immediately exploding so that as it's flying through the air it eventually gets to the point where the air friction sets it off at some point in its trajectory. Does that make sense? The idea is that you would not see anything leaving the launcher but at some altitude/distance away, it would explode into a shower of sparks.....

  • @ramsaranbasnet6050
    @ramsaranbasnet60503 жыл бұрын

    Thank you sir Namaste I look fom Kathmandu Nepal

  • @TheCatherineCC
    @TheCatherineCC2 жыл бұрын

    Yissss, another pyro wesley crusher video.

  • @8hq28
    @8hq283 жыл бұрын

    Like the music!!!

  • @pabitrikalita3940
    @pabitrikalita39403 жыл бұрын

    THIS IS MORE LIKE A HAND CANON, AWESOME JOB MAN AND GREAT EXPLANATION

  • @thedailydaily
    @thedailydaily3 жыл бұрын

    I think this was really cool. The only way I would alter it is to shoot the rod whole and have it explode on impact.

  • @mbmurphy777
    @mbmurphy7773 жыл бұрын

    Perfect for Home Alone!

  • @twocvbloke
    @twocvbloke3 жыл бұрын

    Ah, Ferrocerium, the stuff they built into the bulkheads of the USS Voyager... :P

  • @dimesonhiseyes9134

    @dimesonhiseyes9134

    3 жыл бұрын

    The best material known to man to go into space with.

  • @marks47

    @marks47

    3 жыл бұрын

    Not the walls, the display and control panels.

  • @TrinitronX

    @TrinitronX

    3 жыл бұрын

    Duranium and Tritanium sound a lot like Ferrocerium, but turns out they are more like Unobtainium! 😆😂🤣

  • @thewaytruthandlife
    @thewaytruthandlife3 жыл бұрын

    great for newyears eve...

  • @alexjavanainen4259
    @alexjavanainen42593 жыл бұрын

    Hey nighthawk, coming from someone experienced in modified bullets...ferrocerium can be fully ignited without preheating...provided the velocity is high enough upon impact. Use to put lighter flints in .22 hollow point pellet rifle pellets and shoot those around as a neat party trick

  • @alexjavanainen4259

    @alexjavanainen4259

    3 жыл бұрын

    Since you actually saw this (and I’m extremely excited/humbled) I thought that I should add that the high velocity method of ignition works in much larger scale as well. I’ve gone as far as machining whole “tips” from a store bought ferro-rod and attaching that to .50caliber muzzleloader hollow points (with extra deep/wide hole drilled to allow for more ferrocerium insertion/increased stability). Friction fit and Super glue was enough to hold it in place. When I shot those things....good lord my man....it’s on another level entirely O_o I have photos and video if you are personally interested

  • @alexjavanainen4259

    @alexjavanainen4259

    3 жыл бұрын

    When shot against a hard target, the modified ferrocerium.50cal (out of a muzzle loader) made about a 10-15ft ring of brilliant white hot sparks, with some pieces going well to above 10x that. Truly visually spectacular but terrifying as well. It was a real pain to machine as well since ferrocerium behaves more like a ceramic than a metal, and small chunks of that “ceramic” are pyrophoric. I also only had a hand drill to use as a “lathe” for final shaping (using files and sandpaper) after being affixed to the bullet. (I would put the whole bullet in the chucks of the hand drill and spin it while using sandpaper to shape the ferrocerium tip and make sure the tip was “true” to center of rotational axis)

  • @Tahmanakki

    @Tahmanakki

    2 жыл бұрын

    @@alexjavanainen4259 onko laillista? :D

  • @alexjavanainen4259

    @alexjavanainen4259

    2 жыл бұрын

    @RoskapostU amerikassa se on hyvä