How to Make a 200m Dive Watch for $25 

funny thing is, most guys who wear diving watches have never dive :(

This should work with any casio, right?

With this mineral oil modification, can this Casio be used again, as in change the battery years later, and it will still work?

Excellent !!

Does it leak oil? Cheers Graham

I love this video no 20 minute vlog bs just 100% quality content

Somehow, casio really understated their products, it's a lot more robust than they claimed

Casio proving once again they basically made the perfect functional watch.

0:28 "Watches that do more than keep time. They keep you ahead of your time" Popular in the 80s, 90s, 00s, 10s, 20s, 30s. TRUTH.

My f91w is my go-to watch for surfing for years now and it has never let me down, even when taking 2m waves right in the face it acts like it ain't nothing

The oil filled watch will take a lot more pressure than 20 bar. Another benefit with this method is that you should be able to operate the buttons under water, without water finding it's way into the watch, something you are not supposed to do, even with the most expensive dive watches. I do believe it's a good idea to use silicone based oli instead of mineral oil, though, since mineral oils might have small amounts of corrosive components in them, that might harm the watch over time. I also believe mineral oil will yellow over time faster than silicon oil, but not 100% sure about that.

Poor Casio on the left sacrificed for science. 😔

man my fw91 can handle 30 meters...without oil and stuff

If you press the buttons of the modded one, will the mineral oil seep out?

Hi Everyone! Brett and I are very appreciative of all the support on this video. It has been amazing watching it explode in popularity. And while many of you appear to be watch enthusiasts (myself included), those of you here for the boating can still find us on my channel. Brett and I still make content together and would love to see you over there! We just might drop a few more watches to the bottom 😉

Love my green F91W, it’s my landscaping watch, and I nicknamed it the Master Chief watch.

The only downside is that you need to repeat the process once you need to replace the battery.😅

I've been snorkeling with my stock F91W multiple times in salt water, and never had a problem with water intrusion or corrosion. Those are shallow depths, but I would say that it's more than just "water resistant". (Also I regularly do things like hose off my arms, take showers with it, dip into buckets of water, etc.) This video is a great idea for deeper depths, and it makes total sense. As long as the mineral oil doesn't eat into the plastic casing or gasket over time.

Everyone knows the f91 will survive nuclear fallout

Casio are very reliable watches , my father like the Casio , he have plenty of them from the ealy 80's to today , for every day , they all works. Part of them , on their original Battery .

Ive been using this watch for 3 weeks working 5 -6days washing cars and never had a problem best value for quality!

My issue is what are the long term effects of mineral oil on the internal components, and insulated coating on the pcb.

That's actually genius

My f91w is worn daily in the sea, pool, shower, ecc. after 3 years still perfect…

Very nice. Bell & Ross used this same science to create the hydro max, which is water resistant to 11,000 meters, but costs around $2500

I had a tear in my eye when I saw the Simpsons and Zellers logos

The "depth" rating is actually of equivalent pressure and does not include any increase of local pressure due to currents. So you tested it to a higher standard than what a watch pressure tester would, it's more like the "300M" rating. But hydro-modded watches are known to be practically infinitely waterproof, though with a bubble the caseback might dent in. What went wrong with the stock F91-W is that the inner air compressed so much, that the crystal pressed on the LCD and shattered it's glass. I've hydro-modded a B640M and a GBX-100 myself, with the latter the oil broke the screen, which I repaired with a new polariser. Another benefit is better viewing angles, especially under water, where the crystal doesn't turn in to a mirror beyond a certain angle. It is tricky to avoid a bubble from forming in the plastic housing of the module, which might get out over time. And depending on the used oil it might turn yellow or cause the gaskets to swell, the latter also happened to my GBX-100. Even still, stock F91-W are known to survive being used on actual dives, as Casio greatly understates their water ratings. Also, you commented on dive-watches being too expensive, but only mentioned Omega in the end. Perhaps the cheaper Vostok Amphibia divers, or Chinese imported ones would be interesting too. Just One More Watch recently showed a 1000M rated diver, though it's gaskets were smaller than a Vostok's and the F91-W's.

In theory this should be possible with copies of casio right? I stumbled upon a brand called Skmei and wanna try this out for our next freediving sesh. It doesn't go as deep as the video for sure but it looks fun trying out.

nice 😊 tips! thank you! 200M the watches still workin, but Im die 😅,

It can be used anyway for diving. It is mind blowing....

Didn't know Matthew Stafford did youtube G Shock vids. Must be a slow NFL off-season

Can you still hear the alarm after the mod. Or does the oil muffle the ringer?

Hey thank you for your video this is awesome I've been working around boats for a little while now and everybody tells me to get a watch that's at least 200 m water resistance but I don't really have the money for it and now I have solution to my problem thank you

BRO, USE A SMALLER BOWL

I think this shows that the buttons are well sealed. If the non-oil watch buttons didnt seal, water would have seeped in to equalize the pressure, and the glass might not have broken. Of course, the electronics might have failed eventually in the salt water but its worth testing a pressure- equalized watch.

Interesting video! Just a note: the unmodified watch IMPLODED, not exploded.

Had two f-91ws that I would swim laps in a pool in. They never so much as even leaked. I would dive to the bottom, around 10 feet, and I wouldn’t even get any condensation on the display. Later replaced it with a databank and accidentally went swimming in it. Display fogged up bad but still worked.

Please forgive my ignorance....But.... How does the oil not break the module?

Just buy a Timex Ironman problem solved. I have dove with a Timex for years in water from Michigan to Grand Cayman. Never flooded ! And way easier to set and use than the Casio.

from time to time i wore a DB-56W telememo(50m water resistance lol) while in the military . special forces paratrooper.year 1996 1 day i forgot to put on my G-shock and was stuck with the DB . that day we had a HALO jump which was followed by a sea landing/diving and then swim 300m to the shore . when i was in the plane i thought ''that is the end of the watch'' the watch is still in my possession and working 100% crazy 🤪 🤪

It would be great to do the same with a g shock to see how far past it’s 200M limit

Noob question. Wont the mineral oil corrode the rubber seal?

Спасибо. Потрясающе ! Я заказал бутылку СИЛИКОНОВОГО масла для своих Casio w800 )

Interesting the standard one completely exploded at exactly 200m❤

You could start with a Casio w59 which is about the same price but has better water resistance by default and mod that.

Thanks mate that’s a great idea! I'd buy one but I need a mineral glass face, not resin glass because of my job the resin will scratch and get chipped in no time, but if I find a watch that has a mineral glass face and no real warer resistance Ill definitely have to try this!

omg, my family only wears casio. no money can give the satisfaction and trust like casio does at a fraction.

Talibian special,bet they didnt know about this

Mineral oil eat plastics, you have to use silicon oil.

The complete diving equipment cost a couple of thousands dollar. In case you do not have the 75$ for a G-Shock which you can trust your life under water, then please do not go diving.

Or just add another 25 bucks and get the 200m resistant model

Are buttons still functional ar they will leak oil when pressed?

stupid question but once you've done this mod is there a chance of oil leaks once you start using the buttons?

Actually you can surf or even snorkel in it out of the box. But good idea with the mod. :)

That's nonsense about the F91W natural water resistance. I took it on multiple deep dives down to 100ft and it held up fine. I also took it into the jungle with me and the only thing that happened was I melted the strap due to too much DEET. They are tough watches.

Casio doesn't use philips screws I wish the talking heads would quit saying that. They use a JIS screw, which makes sense considering Casio is a Japanese company ffs

This is cool but Casio already makes a good 200m watch for 30$, the DW 291...

Heck why would somebody go 200m deep. That's pressure of 20 atmospheres.

mineral oil degrade rubber and plastic after being in a contact for a while. use silicone oil instead.

The magical part is that for 10 bucks I’ve been pushing it to the limit with no fear and it’s always responded perfectly. If anything went wrong (for two years it hasn’t) you can learn the lesson and get another one

А звуковой сигнал в часах работает после залитые масла во внутрь?

Freakin Google i just told my friend about this watch and 1 hr later this video appears on my list

Instant sub. This is the type of watch content I've been waiting for.

A bit messy and unnecessary when you can usually get the Casio AE-2100W for half its listed price, at about 30 quid (i.e. probably $30 in the more favourable US market). That’s 200m water resistant and has a nice stainless steel front piece, mineral glass, a ten year battery and all the bells and whistles of the Royal, but with nicer looks.

Im really Happy.I can now dive 200m or maybe more with this insane mod jipiieeejaay

when any button was pressed oil will leak out and the space will fill with air or the button will not press back. its one time modernization, not for conctant use, i think

Won't the internal components get spoiled with the oil??

"fluids are virtually incompressible, but the inside of our watch is filled with air." Not to be a nerd but air is a fluid

Very nice. Thanks .. see you. València Spain. 46006. 4:23

They have a crappy light tho. If you want a cheap dive watch, do this same mod to an A168.

Bruh that bowl could fit 20 watches at least. Could’ve done it with a cup

So if a G shock get mineral oil it can go 1000m

Excellent demo. And with the humble F91W too. Great job.

Can u do it with a new vintage addition ABL100

Anyone mentioning that badass gopro holding on those 200M???

Для аналоговых часов метод не подходит?

How long will the mov't last after being doused in mineral oil? It may be WR to 200M but a movement full of oil is likely to stop working soon.

Robinson Susan Hernandez Ronald Harris Patricia

Вот это я понимаю модификация! Моё почтение автору!

imagine doin this to a G shock

How is this possible, with the buttons.... They are not sealed, why does the oil does not seep out of the whole were the buttons are?

I usually dive with mine…. 30/40 meters

What if you pushing the buttons? Where the oil goes?

why did he stopped making videos is he on a different platform?

Don't think f91w needs any modifications

i swam miles with the F91 and it didnt bat an eye, strap needs to be textile though as the resin one disintegrated fairly quickly

I ❤ Casio. Se o mundo acabar em bomba atômica, só restarão as baratas e os relógios Casio.

Nice, but not a big fan of this mod. So when the battery goes flat, you dispose it?

Casio mrw 200h testing please

The truth is that , the American’s make this cheap watch famous & popular more than Japanese 😂

А как часто эту процедуру повторять нужно??🤨

Question #1. If mineral oil is not a conductor, what happens to the contacts from the battery to the contacts to the watch? Question #2. Oil is more viscous than air. In the case of classic watches. Will the viscosity of the oil affect the rotation of the needles and gears? What about the battery life?

can this be done to cheap analog watches that are not branded and not at all water resistant?

more oil is needed. A 110 liter bath will do.

why not tested it past 200m? see how deep it can last...

Now the remaining piece of the puzzle that will probably destroy all dive computers is adding a depth gauge to this bad boy ..

Casio are the watch goats

That's incredible 😅🤓😅♉👍💪♉

did someone try to oil fill the smart watches?

Bro your content is quality content 👌 ❤