Scuba Tech Tips: Steel vs Aluminum Tanks - S03E07

good morning divers it's Alec Pierce again from scuba mm on the tech tip and I did say good morning it's 6:30 in the morning maybe I look a little blurry that's the only time we could get studio time Kevin our cameraman it was late booking so here we are in the studio I'm kidding we're at scuba mm anyway guess what we're talking about today just look down here Kevin just for a moment guess what we're going to talk about today exactly right tanks and the reason for that is somebody called the other day or somebody emailed the other day to ask about tanks and steel tanks and den valves and so I'm not sure you can or didn't notice but we're going to share that very quickly with you today maybe it'll give you some information some good clear information that will help you make your diving a little safer or a little more fun that's the whole idea of these tech tips hope you've been enjoying them and thanks to everybody for your comments I can't believe how many I get anyway tanks tanks are really important to scuba diving air underwater is so important you have no idea and anyway so I'm not talking about talks now this is this is the tank that you all use I would be willing to bet you that every scuba diver who's you know who started diving after 1985 trained and used and still uses when you travel this tank right here this is what's called the standard 80 cubic foot aluminum tank it's made of aluminum which is new they started coming out in the 80s and they have pretty much replaced every other type of tank on the market so it's aluminum tank very thick walls very strong and has a standard valve on top to put your yo-yo regulator on straightforward when you're rented tank when you go south for dentists what you get 80 cubic feet a 3,000 psi 3,000 psi is the pressure of this tank standard this is it this is the standard for other extinguishers are all painted red always this is the standard tank this is what you get 80 cubic foot aluminum but there are other tanks and somebody did ask you today but steel tank jet steel tanks all tanks at one time were made of steel at one time aluminum was very very expensive steel tanks ed started coming out for scuba diving and in the probability of late 40s or early 50s I actually have in Michael action some homemade Jencks you know we actually used to make them as three homemade Scoob units homemade tanks there were tanks that were taken from aircraft and modified and homemade regulators yeah believe it or not maybe I'll show this to you sometime so back then steel there was very little aluminum so they were made of steel steel a strong was cheap and remain the first excuse me one minute the very first steel tank and the one that was around for many many years this was the standard tank before the aluminum ad for many years this is what it looked like this was the standard 72 cubic foot tank now you can see that this tank is a little smaller a little physical little smaller the smaller diameter little shorter not much and this tank was the standard tank from the 50s to the 80s over 30 years and if you ask any diver who's been diving for more than 25 or 30 years about his steel 72 he'll he'll smile and reminisce oh I had every great tanks and there were a lot of fun there were a little lighter than aluminum that's kind of weird isn't it they are lighter than aluminum the reason for that is simple although aluminum metal is later the walls of aluminum need to be much thicker too steel tanks are thin walls is less steel so they are actually lighter and not as much pressure not as much air the the 80 cubic foot tank I showed you holds 80 cubic feet in theory but lasts for 80 minutes at the surface and of course that depends on it varies over depth this is a 72 cubic foot tank now that's a little bit funny too because here's here's here's an opportunity for you to win a free beer with some trivial although it's called 272 it actually holds 70 1.2 cubic feet they're rounded up the 72 because it sounds like more that's called salesmanship you see but even that's kind of interesting because it doesn't know 70 1.2 unless it's overfilled by 10% so it does have a stamp to pressure on here you can see that the stamp pressure on this tank is 2250 2250 psi that's the stamped pressure but if you take a look at the very first examination this tank was made in the third month of 61 March 9 favorite market March of 1961 see little plus sign that plus sign meant that we could fill this tank to ten percent more than 20 to 50 which is 24 75 at 24 75 this tank holds 71 point 2 cubic feet or 72 okay however after the first five years there's no more pluses this tank has had lots of extra visuals lots of the mistakes been around a long time suspense tested visual stachy tested several times there's lots of stamps on it and all the subsequent stamps do not have the plus sign hence no 10% overfill so this dangle only holds 65 cubic feet okay so it's a 72 cubic foot tank that holds 70 1.2 Q feet but actually only 65 that's got it when you have free beer and the bar with a bunch of divers and all you got work on a trivia question there anyway this was a standard tank you see the valve was different - this was called the pillar valve different from today's valve the knobs on the top and the old ring a little bit different big and fat there weren't very good back then and you'll notice the neck as well you see the teflon tape the sealing tape this valve did we didn't have o-rings very good orderings so this this valve was actually forced into the tank sealed with some tape teflon tape and then of course with a great big barn forced into the tank to make it seal nowadays you can take that valve off by hand so there are a few differences but this is the original steel tank they're not used much anymore so my vintage divers use them we actually do a lot of dentists diving and vintage divers will get these old tanks make sure they're safe save the hydrostatically test the visual exam we talked about that in a previous tech tip and I'll make sure they're safe when they fill them up and they go diving is a whole lot fun however this tank is gone so we have the aluminum 80 but there are steel tanks yes there are new steel tanks let me get one for you that's here's what it looks like here one right there a nice and new we clean always ever nice and new and clean so here's a steel tank that's what it looks like today same valve as our old 80 same valve because we use the same regulators and this is a new steel tank brand-spankin'-new made by a company called Faber and and these tanks are heavier than you lumen them tanks because now these are higher pressure so to accommodate the higher pressure now the walls are a bit thicker so now the weight difference of the steel versus aluminum comes into play and this steel tank is now heavier than you lumen them tank you see the pressure on this tank is three four four to three thousand four hundred and forty-two psi a little more than the three thousand of the aluminum and it has more air as well this particular tank has a hundred cubic feet so start at eighty give you feet you have a hundred K that's 20 cubic feet more that's an extra 15 minutes that's the bonus particularly if your person may be a little bit bigger and maybe not as efficient in the water and you use more air than your buddy if you had one of these tanks 100 s they come in 120 as well but if you had a 100 that we give you an extra 15 20 minutes worth of air so you and your buddy would get out at the same time so what's the difference between this steel and aluminum I know one steel ones like me what's the difference practical difference the only real practical difference is the higher capacity at three four four two this has more air same size as the 80 pretty much the same size the other difference is because this tank is heavier is made of steel it's more negative so some divers like to have a more negative tank what that means is they can take a little weight off their weight belt if you're diving in cold water wearing a wetsuit or a dry suit you could be wearing as much as 25 or 30 pounds of weights it's a lot of weights if you have this tank on you can take off five or six pounds wear less weight so that's another small benefit or the disadvantages to a steel tank there's always give and take on this right the disadvantages there's also two disadvantages the first disadvantages are very practical it cost twice as much you're gonna buy a Lula Mae T tank and Alber under $300 commonly $200 if you shop around a little bit steel tank like this is over five over five hundred dollars again sometimes you can shop around and get one for Round four twice as much money so you really have to think do you need that extra 15 minutes of airtime if you do you do they're pretty popular though the other rap practical that problem disadvantage to steel tanks is it take it be very careful with them because your steel steel does rust so all the rules that apply to aluminum tank never let it get empty don't drop it take care of it apply even more so to a steel tank isn't very important that the steel tank is never allowed to get empty if it did get empty then moisture salt water moisture might get inside the tank and in a steel tank it would act very very quickly to destroy the tank but other than those two disadvantages of steel tank is it's pretty popular still it still doesn't begin to come near the popularity and the end of use of the aluminum tank but it's pretty popular so that's some of the questions and answers about steel versus aluminum I did want to show you another thing at the same time somebody else asked about are the different types of valves and there are different types of valves the valves are related to the regulator take a little peek right here Kevin this is a regulator first stage that you're all accustomed to a first stage and you take out the dust cap and it fits over the valve like so you've all seen this you've all done there's a recently put online there go this is a yoke type regulator and fits right onto this tank no problem and this is what we're most most got accustomed to but look at this here's the first stage as well what was this where's the yoke there is no yoke on that what pull off the dust cap and has threads what's with that well this is called a dim di and I could tell you what din means but it'd be easy if you googled it I looked it up my German pronunciation is not very good so you look it up it is it is a German technical term it's been shortened to Denver for us in North America and and the din regulator fits into a din valve di an this is what it didn't valve looks like a threaded what it makes sense because the first stage is threaded so with this particular regulator valve combination you put the threads in legs so and you just screw touched there you go simple huh just like that now some divers will tell you that the den is better be very very careful whenever somebody says better you know google call me do something unchecked because better is always relative first of all if it's better here then it may give up some advantages here this is a little more expensive the den probably because it's not quite so common but some drivers say the den is better as stronger yeah you know there is a reason for for a DIN valve and and in regular there's a reason for it's a very practical reason the good old staggered yoke that we all love and use is rated and tested and rated to be used to pressures up to 3000 29.99 to be exact at sorry 3,500 3,500 so that would be $34.99 to be exact once you hit 3500 psi then the yoke is deemed to be not as good not because you yoke isn't strong the actual steel yoke itself is good to 4500 psi but the way that the o-ring fits into a yoke type val is sealed with a yoke type regulator there's not quite as good a seal is with the din perfectly fine up to that 3500 psi but once you get over 3500 psi then that way that the o-ring is held in there's not quite so good with the din the o-ring is what they call a captured Oh ring is held in a little more securely surrounded by steel seals tightly and when this is screwed down seals tightly in there so the o-ring can't extrude can't pop out that's what extrudes a fancy word for a pop-up so it can't extrude under the higher pressure so if the tank pressure gets over 3500 psi then you must have a din just that simple you can't use a yoke it was under 3500 psi you can use you so one is not better than the other that's a practical other thing you know if you have a car that goes 200 miles an hour you need special tires you don't need those tires on your Honda Civic same idea tank pressures up to 34 99 3490 of that rate ya $34.99 and the yoke is perfect 3500 and higher you must use add-in not better just a matter of technical necessity and this particular valve as a matter of fact this particular tank is kind of interesting you notice if the precious 3442 why did they choose 3442 was a very simple reason if they had gone to 3500 they would have had to have a dinner only he would not be able to use a yoke on this but with this particular steel tank one hundred and hundred cubic foot at 34 42 you can use your yoke regulator or I didn't have you prefer so it's convertible as a matter of fact this valve that we have here as you can see din right and then you take this din insert it's what we call it then insert and screw it in like so and now it becomes yoke because it's only 34 42 if this was a 3500 psi tank and they make them 35 and higher actually if it was the 3500 psi tank you would not be able to use a yoke on it you would not be able to use that insert I hope that's clear a little bit confusing but hope it's clear all tanks up to 34 99 psi can use a yoke under your regulator is perfectly fine just as good strong as anything else as soon as the tank pressure gets above 3,500 3,500 or above then you must use it in I hope that's clear don't forget to look up dinner Google so there's some some some ideas and some thoughts and some answers to some of the questions that you've been sending me about steel the old steel the new steel in the aluminum the differences between them din and yoke I've addressed a little bit you may have some more questions sometimes when they do these tech tips I get more questions than I'll answer but anyway that's always good I really really enjoy the comments and the questions you've been sending me I try to get back to them as many as I can if I if I miss one or two please forgive me and I hope you keep watching our tech tips I hope that was interesting and answered a few of your questions okay that's it I had to go get some sleep now thanks guys Alec Pearce tech tips from the skew of a 2000 you

Channel: Alec Peirce Scuba

Views: 67,051

Rating: 4.8937445 out of 5

Keywords: scuba tech tip, tech tip, scuba tip, underwater, scuba diving, local dive shop, scuba, scuba tank, steel tank, aluminum tank, catalina, steel vs aluminum, aluminum vs steel, DIN, tank valves, 80 cu/ft, alec peirce, alec peirce scuba, scuba 2000

Id: 3ituzTB7zdw

Length: 14min 47sec (887 seconds)

Published: Tue Mar 22 2016