Why Do Ships Have Two Balls?

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In this video, we investigate the magnetic compass used on ships and discuss the correctors needed to keep it accurate.
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[@StickerWyck]

It's like 10% of engineering is to use the laws of nature and the other 90% is to counteract it's unwanted nuances.

[@FFFFFFF-FFFFFFFUUUUCCCC]

sneed

[@crabofchaos7881]

​@@FFFFFFF-FFFFFFFUUUUCCCCyou stop sneeding or else

[@FFFFFFF-FFFFFFFUUUUCCCC]

@@crabofchaos7881 ok I stop

[@crabofchaos7881]

@@FFFFFFF-FFFFFFFUUUUCCCC or else I fart

[@sierraecho884]

HAHAHAHAH genius xD @@FFFFFFF-FFFFFFFUUUUCCCC

[@OnionChoppingNinja]

"Why Do Ships Have Two Balls?" " one ball on each side of a central tower" nope. couldn't keep a straight face.

[@haraldviberg534]

same

[@watcher1421]

What's funny about Kelvins balls!? 🤣

[@xp8969]

Your gay face casually navigated it's way out

[@ImieNazwiskoOK]

@@watcher1421 Hey you! You better not mess with navigator's balls!

[@Bronze_Age_Sea_Person]

Don't forget the shaft that corrects vertical soft iron magnetism. Correction is made with both the two balls and the erect shaft.

[@djmit44]

I honestly can’t believe how clearly you’ve explained such a complicated engineering challenge! This is spectacular.

[@JohnnyAngel8]

It might be clear to engineers but not to me.

[@jamesretreat]

Do you seriously go into everything with that sort of mindset?

[@olspanner]

You mean you got all that the first time!!!

[@mikerichards6065]

Kelvin Balls -named after William Thomson, later Lord Kelvin. When not making navigation safe, he gave us the absolute temperature scale named after him; the first and second laws of thermodynamics; developed the first devices capable of accurately measuring electrical forces; who helped perfect the Transatlantic telegraph cable; and invented 'the siphon recorder', the ancestor of the inkjet printer.

[@sierraecho884]

Kelvin has earned his massive balls I would say.

[@TheFeldhamster]

​@@sierraecho884🤣🤣🤣

[@ethribin4188]

Great man

[@sirllamaiii9708]

He helped invent the inkjet printer and Big Printer's iron grip on the toner market? For shame

[@Blaze_1961]

We called them binnacle balls when I was in the US Navy.

[@arjenmiddelb]

They are shield generators. Destroy them and take out the shields quickest.

[@antonliakhovitch8306]

LSW TCS FTW

[@stevennotthe2997]

Now the houthis will sink all the cargo ships

[@jeffbenton6183]

"Intesify forward fire-power! I don't want anything to get through." "INTESIFY FORWARD FIREPOWER! "Tooo late!"

[@ChrisParrishOutdoors]

This is why ships have seamen

Brilliant! 😂😂😂😂

[@SirArghPirate]

Salty seamen.

[@Oof-th5hz]

​@@SirArghPirateAYO? AYOOOOOOO??

[@ghostemptation8979]

if ships have balls why are they often referred to as 'she'??

[@keiyakins]

​@@ghostemptation8979 because they're a form of TRANSportation

[@SeattleBoatdog]

Old former compass-swinger here … You do an exceptionally solid job with your explanation.

[@voiox]

Is your professions logo an magnetic flamingo?

[@taitano12]

Thank you for the memories. As I listened to your explanation, my late maternal grandfather's voice was echoing in my head as I remember him explaining his craft to me. He was a Professor who taught Navigation, marine focused Wireless Communications, and Naval History. He was also one of the best Compass Adjusters on the West Coast. He died of cancer in 1993. His name was Robert E. Larson. I was just a baby when I first met the sea Twas my father, grandfather, the Skipper, and me. The salty sea splashed me, I started to cry. Grandfather smiled, then laughed and asked why "That means the sea likes you; she gave you a kiss. So blow a kiss back and say 'Thanks' for the mist." Now, all these years later, on the South Salish Sea, With memories of father, grandfather, and me, I stand on the deck of the Samish ferry Getting salty sea kisses from my Lady, the sea.

[@chickenfriedchickenn]

This is beautiful. Thanks for sharing. Your grandfather sounds like he was a wonderful man.

[@ardeladimwit]

thanks for that

[@Martcapt]

I thought this comment would go into a completely different direction.

[@toddbrown4935]

thanks for sharing this

[@nunyabusiness9013]

Bukake metaphor

[@PLANE_BOSS]

"Why do ships have 2 balls?" Me: *sighs and opens comments*

[@MariaMartinez-researcher]

It was *after* I opened the comments that the "2 balls" situation presented itself. Ace. Definitely.

[@UKMonkey]

So - looking after your balls, and even shaft, will keep you on your desired heading - ensuring that your head isn't sullied by any unexpected grounding. Gotcha.

[@52HzWhaleMusic]

Boats are so interesting and goofy. Every single one of your videos is "the bibbledy bung ties together the weedlethin pump, and that's why Sir Andrew Thorne's Crispy Knuckle goes to wayside." And I love it.

[@CyclicPilot]

Kelvin wasn't happy when his port ball fell athwartships...

[@bryanpritchett]

Each of these videos is kind of like a multisensory Patrick O'Brian experience. I mean that in a good way.

[@drworm5007]

I'm just replying so the machine spirit knows this is a good comment.

[@thelazione6236]

bump

[@joule400]

me: such a nice educational video as usual also me: very maturely laughing at navigators balls

[@jovetj]

It does take balls of steel to think you know where you're going on the big, open ocean!!

[@damiencouturee6240]

​@@jovetjLmao alright, that was good.

[@Combes_]

​@@jovetj And a lot of seamen!

[@RammusTheArmordillo]

very surprised to learn that a "monkey island" is an actual place on a ship lol

[@Halinspark]

And apparently the Secret of Monkey Island is Kelvin's balls.

[@richardcranium3579]

@@Halinsparkand he paints them red and green……better than blue I guess

[@yetanother9127]

It's synonymous with a "flying bridge" if you want something to Google.

[@TheRoostersGarage]

Wow!! I always wondered how a compass in a metal ship was even remotely accurate. Now I understand there are a lot of things at play I never knew. Thank you for a very good explanation on a very complicated topic correcting such a simple navigation tool.

[@TheRoostersGarage]

@Ronaldo-ue5if Thanks for the offer, but I'll stick with the one true God

[@jorgicostava7217]

More than three decades have passed since I first played, "The Secret of Monkey Island." Only *now* am I learning that "monkey island" was a double entendre. Nice video!

[@Welgeldiguniekalias]

Same here, I had no idea.

[@garybuttherissilent5896]

Nice comment!

[@banba317]

Wow... who knew how complicated this process is? How much trial and error it must have taken over many years to fine tune it! Fascinating!

[@corolla94]

This analog way of correcting the liquid compass is very interesting. In robotics, we normally take readings at various rotations and compensate mathematically.

[@richardcranium3579]

Many men compensate by getting a bigger boat.

[@dougaltolan3017]

That's called a deviation chart. It's easy for electronics to take a reading, apply the deviation and obtain a true result. For people, that extra step is a pain in the butt, so correcting the sensor is preferable.

[@argonk]

I spent 25 years with the only notion that they are "to compensate for magnetic interferences", but never investigated the heart of the matter. Thank you for this video. How revealing! Would be interesting to know how to correctly dimension these balls and the other devices.

[@alextheboatguy399]

This is why ships should be referred to as males

[@KG-ds2fj]

Nah

[@ham4da]

Yah@@KG-ds2fj

[@ClyxoWTM]

NAH FOOL

[@alexandruraresdatcu]

Except the wooden ones, and the glasfiber ones,... and the carbonfiber ones,... and the aluminium ones....and the stainless steel ones....

[@CMDRSweeper]

Interestingly, the Russians refer to ship as males, while the west uses female designation for them.

[@jbran7817]

Can’t believe people are making crude jokes. There’s nothing funny about seamen using the balls on the binnacle ensure the ship can be directly inserted into a port.

[@johnt.inscrutable1545]

Great explanation of “Swinging the Compass”. The same kinds of problems occur on airplanes as well. We have to record the errors that remain on a small card that is kept with the compass for our Cessna 172. We also want to take into consideration that vertical component that will cause a compass card to dip as one gets closer to one of the poles. The dipping of the card can actually cause the compass card to get stuck and not spin toward its new reading in some cases.

[@tomkandy]

Wow, I knew the approximate function of a binacle, but no idea how it actually did the compensation. That's a fascinating technology, and much more complex than I imagined.

[@bluekewne]

Well you see when a mommy ship really loves a daddy ship...

[@ImieNazwiskoOK]

... and after some time they give berth to a baby ship

[@jacobcave1587]

Oh god 😂

[@TheJohn8765]

Damn. Ingenious and yet so simple. So 'simple' I wouldn't have thought it was a problem until I ran into a reef. Institutional knowledge is fantastic (and humbling). Thanks so much for sharing!

[@JavierCR25]

This is by far one of the best videos you’ve made. Not only is this a very obscure fact for those of us who don’t know much about ships, but the explanation was brilliant.

[@MervynPartin]

That was absolutely fascinating- a far more complicated set-up than I had previously thought. I've searched my now-fading memory, but I do not remember magnetic compasses on any of the ships upon which I sailed, although I have seen these binnacles elsewhere. I remember the gyrocompasses. Iron ore from Canada was a frequent cargo, so I imagine that prior compensation for that would be very difficult for magnetic compasses.

[@julianbrelsford]

Nowadays just have your GPS device tell your your position, speed, and direction?

[@yourpalpalmetto979]

@@julianbrelsford it's always good to have backup equipment and especially goof to have them working independantly of your electronics.

[@ralphwaters8905]

I had a magnetic compass in my car many years ago and the effects of chassis magnetism were significant. It was educational to watch the compass needle jump when I hit the starter and 500 amps flowed thru the battery cable and the motor's windings below the transmission.

[@wormyboot]

I've been designing a modern nation to use in a novel I'm writing and you've made things more difficult in the most fascinating way. I love your channel.

[@hchskxnbcj]

Have you already thought about the shift of the whole earth's magnetic field which also has to be thought of?

[@DreadX10]

@@hchskxnbcj And how about local deviations due to large iron-ore deposits (for example) in the Earth's crust? There are places on Earth where the resultant magnetic moment is so weak that the viscosity of the fluid the compass is floating in starts to interfere with the motion of the disk.

[@dandinzin]

You knew exactly what you were doing with that title and thumbnail

[@monabuu]

"Kelvin's Balls" is truly one of the names of all time

[@cameronland5934]

"All ships have a box with one ball on each side of a central tower", yet ships are still referred to as she.

[@RJNoe]

Because it’s strapped onto the ship

[@thelastwoltzer]

That's exactly what I thought 😅

[@carltonleboss]

They're also filled with seamen

[@joostvhts]

Haven't watched yet, but based on the title: how else would we get new ships?

[@jimturpin]

I have seen those balls, I knew they had something to do with correcting the magnetic error induced by the metal of the ship but I had no idea of the extent. This video sort of blew my mind!

[@PianoKwanMan]

Imagine trying to explain this on a blackboard... 🤯

[@BDCF100]

Before I watch your video I'll amswer the question. A long long time ago when I was a young man working as a Gyrocompass Mechanic for the U.S. Navy I also had the job of calibrating Magnetic Compasses on Surface vessals and Magnesyn Compasses on submarines. All Magnetic Compasses had a series of straw magnets in the column supporting the compass and there always were two round soft Iron balls mounted to the Port and Starboard sides of the compass. The Iron balls (referred to in the Navy as "The Navigator's Nuts" would be shifted in or out to compensate for the long vector of magnetic steel in the particular ships body. When calibrating the compass the ship would steer courses at 15 degree increments around 360 degrees. Marking down the error amount and direction that the compass showed compared to the actual ship's course I soon had a chart showing the compasses accuracy or inaccuracy in all directions. Then shifting, adding, subtracting, etc. the straw magnets to compensate for the errors which are caused by the steel in the ship's construction I started to correct the compasses errors. Usually I could get the Magnetic close to 1-2 degrees max error and most of the time closer.

[@fuzzygenius]

A great practical application of what I learned in my electromagnetism course!

[@calex007]

Gotta be one of the best videos you’ve ever made. Thoroughly fascinating at well explained. Thanks, this is wild to think about!

[@Shinyworldwide]

so if one gets kicked by a woman they still have another one

[@danielhale1]

This is a lot smarter than my first idea, which was "Hold the compass really far away from the ship and hope". :D I'd never noticed this about ships before but it makes perfect sense!

[@stevenharpervw]

I watched this. I understood it. Still couldn’t explain it to anyone else and have no idea how engineers even figured all of this out

[@timharig]

Math. This is simple vector arithmetic.

[@kennethjackson7574]

It wasn’t all solved all at once. For instance, it was Flinders who understood that the Earth’s magnetic field has a vertical component to it and developed a way to compensate for it. One problem, one solution to that problem.

[@depressed_neutron]

Probably the weirdest title of a casual navigation video 💀

[@FriendlyAC130Pilot]

He knows exactly what he's doing 😂

[@antoniolewis1016]

Thank you, as a resident of a landlocked state I really appreciate this information!

[@freeagent8225]

You can say Afghanistan😅.

[@mumujibirb]

ah yes, more calibration magic

[@edster1000]

I never comment on stuff, but this is great. I'm doing a course that requires an understanding of this but never to actually adjust anything. I get it now. thank you

[@riptide8103]

In the Coast Guard we just use a deviation table, with different values for each heading, but this is cool to.

[@exoplanet11]

Fascinating. I'm so glad GPS technology didn't come along earlier. It is so cool to think about all of these factors as the earlier ship designers did.

[@zoiuduu]

well, i assume a submarine also has a compass like that, and it cant use gps

[@BoopBobBeep]

It took balls to operate a ship!

[@callistofluff]

In both ways

[@callistofluff]

What@Ronaldo-ue5if

[@michaelguerin56]

Thank you. I had wondered how the two visible balls could do everything and now I know that are just one part of a more complex system.

[@starbomber]

I've calibrated an aircraft compass. Similar principal but a radically different looking device. (There's also a lot less iron in an airplane, not as much less as you might think, but certainly a lot less than a ship. The radios cause more interference in an airplane :p )

[@YounesLayachi]

What part of a plane is made of iron ? Also a typical cargo or passenger plane is at least 100 times lighter than a cargo ship

[@stevenschnepp576]

​@@YounesLayachi Hence the parenthetical note.

[@b43xoit]

Principle.

[@starbomber]

@@YounesLayachi the base structure is usually steel, or a steel aloy (which has iron in it.). The skin is aluminum and some of the frame can be, but a lot of the structure is steel. Titanium is sometimes used but that metal is very expensive so, the entire plane can't be made of titanium unless you have infinite money.

[@hart-of-gold]

A quick google search shows a wide use of the pun. And it is named for Matthew Flinders who was the first to circumnavigate Australia (the reason I was searching (Aussie)).

[@randomdude8877]

Very interesting insight about the magnetic compass

[@GHTOONGHTOON]

This is why Seamen have Casual Navigator...Cheers for the amazing , on point and explicit sharing/knowledge :D

[@xnatov2334]

Can relate to it

[@christ1946]

All big ships need to be very brave in the high seas so they give them balls of steel.

[@nicky_kitty_777]

cursed youtube titles that should be illegal

[@Todd66]

I had zero clue this was a thing, but it makes perfect sense when presented in such a easily understood and assimilated format. What a cool channel

[@derHutschi]

great explanation most ships also use a gyro compass and have the magnetic compass as a backup

[@Chris-hx3om]

A gyro compass sill uses a 'north seeker' to counter the 15 degrees per hour drift (thanks Bob) due to a gyro being locked to the universe, not the Earth. A magnetic compass isn't just backup, it's required by maritime law.

[@filanfyretracker]

@@Chris-hx3om makes sense as a law, a magnetic compass requires no external power. Unless its physically damaged it will very likely always work. A good compass, a clock and a sextant and a ship can be navigated if all electrically powered gizmos are not in a reliable state for some reason or another.

[@PhillipBicknell]

I was briefly a suspect during my Day Skipper practical when the electronic compass on the yacht went wrong - the skipper knew I'd bought a large stainless steel cooking pot in the previous port. Thankfully, he soon ascertained that my purchase wasn't at fault, and to this day - over 20 years later - the pot still serves me well for a monthly batch of stew 🙂

[@simonabunker]

Do commercial ships ever get degaussed? Or is that more of an anti mine precaution for military ships?

[@PrezVeto]

Why would they? Just for the astronomically unlikely case they encounter a mine? To avoid disrupting their magnetic compass a little bit?

[@PrezVeto]

Maybe I should watch the video first. 😅

[@PrezVeto]

Yep, I should've.

[@dangerousnoodle8779]

Cost I imagine. Degaussing isn't permanent and ships would have to get degaussed regularly. Seems infinitely less complex and cheaper just to stick some magnets in the compass and call it a day, especially in the age of GPS

[@ImieNazwiskoOK]

​@@dangerousnoodle8779 Way more complex and expensive than GPS but in principle there are also gyro-compasses (and them as well as GPS tell the true north quite easily)

[@kdupuis77]

Excellent video! Nowadays, ships are required to swing annually (or as needed after major maintenance or alterations) to develop an update deviation card, with a certified compass adjuster present to make any needed adjustments biannually.

[@MrEwoud342]

Could have used this channel 10 years ago in maritime academy. But great explanation , keep it up.

[@DuckyTheFox]

Never before have I seen a video about balls that was so informative

[@Luke-bf1wt]

to find if it’s a mail ship ofc

[@dougf94912]

Excellent explanation and clear simple graphics, as always!

[@dimitri_1of1]

That title is a mouthful

[@Hybris51129]

My question is when all of this was discovered and figured out?

[@thisnicklldo]

Mostly between 1850's and 1880's i.e. in the first 30-50 years after iron ships became the dominant form. Some stuff was known earlier, and I imagine the precision of the adjustment increased steadily over the following 150 years, like most machines.

[@thisnicklldo]

@@mckidyl70 Knowing about magnetism isn't the same as swinging a compass, is it? Show me any evidence for Egyptian use of magnets and soft iron to adjust compasses in binnacles.

[@craigcorson3036]

I've always known what the binnacle was for, but I've never known just how it worked. Nice explanation!

[@ViacheslavTaran]

This whole channel is so good!

[@ViacheslavTaran]

I agree.

[@haraldviberg534]

Did you forget to change your acc?

[@flightmaster178]

My wife and I were just wondering what those were for. Thank you for the clear explanation and video!! Also, it's crazy how fast they realized this when shipbuilding with iron ships. Ships such as the Titanic had them, and I was on a WWII ship that also had them. So it really shows there were insanely smart people back then.

[@dj_laundry_list]

Makes me wonder why I have the same

[@soloperformer5598]

Absolutely fascinating, I had never given that any thought.

[@soloperformer5598]

@Ronaldo-ue5if What is this allah thing?

[@jarrodfreeburg979]

Epic title

[@JanRademan]

Any technology sufficiently advanced will be like magic.

[@Chiberia]

Ngl, since you've teased this video I've been thinking about this a LOT. I purposely didn't look it up so I could wait for your video. I made an audible "YES!" When I saw it on my feed, and now I have to awkwardly explain what a geek I am to my wife.

[@TuriGamer]

Well thats a rude question

[@Varangian_af_Scaniae]

Really interesting video about something I have never heard of before. A follow-up video about when they noticed this magnetic behavior and when, how they/who solved it.

[@randomcontent1736]

tldr: because if one is destroyed by for example a kick theres another one

[@markinipannini]

"Why do ships have two balls?" Well where else are they supposed to store their pee?

[@Vivi-yw1eu]

Amazing title

[@IO-zz2xy]

I had no idea it was such a complex problem. I do know that aircraft sometimes have to "swing the compass" to recalibrate them from time to time.

[@Geckuno]

There is you and there is the Lock pİCKİng Lawyer, both great at their respected jobs, and even if I don't understand everything I get and idea, and furthermore its a delight to watch both you guys' videos. Thank you

[@TheGreatGastronaut]

In all seriousness, thanks for the education about all the components of the binnicle. I thought it merely a stand for the compass.

[@srhenryx7416]

Ship just like me fr

[@davidhill5798]

Not sure why you called your channel "Casual Navigation" -- you explore serious topics in great depth & detail ! Thanks for the excellent education. !

[@freesk8]

Cool! Thanks! I had always assumed that having the green and red balls had something to do with preventing some kind of psychological disorientation in fog or rain? Glad to know the right reason!

[@ErnestoGluecksmann]

I'm going with gps. This is way too complicated.😂

[@bigtall25]

I think most ships do use true north instead of magnetic north for most applications, but it's still handy to have a compass around.

[@HugeRademaker]

Clearly you have no idea how complicated GPS is. 😅

[@ErnestoGluecksmann]

@@HugeRademaker True. True. Yo, Casual Navigation. We need a video on it! 🤣

[@christopherness4274]

Thank you. That is so much easier to understand than the Bowditch 'Practical Navigator'.

[@maastricht.mapper]

It's because they aren't an Austrian painter

[@whitcwa]

A great explanation! I never knew how complicated compass compensation was. When I visited the battleship USS Iowa I found the binnacle tucked away in a area which was not normally manned. There was a sign nearby which said something like "NO CUTTING OR WELDING IN THIS AREA".

[@bagochips1208]

Pee is stored in the.

[@ajdutari]

These 8 minutes summarized a full lecture in the topic. We are only missing the practical calculations for error correction. 😮

[@lioraselby5328]

Ships are trans women, confirmed

[@PrintScreen.]

Nahhh, they're Futanari, way better

[@PrezVeto]

Somewhere Greta is scowling

[@johnmacdonald1878]

Probably one of the best explanations of this I’ve ever seen. Even though I’m supposed to know how it works it’s always seamed a little bit like black magic.

[@robbabcock_]

Thanks for an amazing & fascinating video! I had no idea about this. What ingenious solutions!

[@donscheid97]

Airplanes, made of MOSTLY aluminum need to be recalibrated as well and each plane has a magnetic "standby" compass above the windscreen and separate from instruments with the correction card below it for crew to read accurate direction in emergencies. The compass for instrument readings is in the right wing tip away from as much interference as possible. Of coarse we also have GPS now. Just thought I'd add this.

[@christheone248]

I;ve never heard of this before! I would not have worked out this problem in a million years! As they say never to old to learn!

[@robertheinkel6225]

No gps? In the military, our aircraft have a backup magnetic compass. It takes hours to calibrate them. An aircraft that is hit by lightning, can magnetize the windshield frame, messing up the backup compass.

[@michaelfisher7170]

I learned about ship's magnetism today! Thanks for the vid! New subscriber!

[@infinitecanadian]

Because one ball isn't enough, and any more makes it too hard to move!

[@peterheinzo515]

a normal person would think a compass is pretty straightforward, but as with almost everything in our modern world, it is way more complicated than that.