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Lloyd De Jongh
01-07-2008, 01:20
Hi all

I'm a recently qualified PADI OW diver. I don't yet have a full complement of gear (the selections have been made though), however I have great confidence in making purchases from ST.

I need advice on the Neutrally Buoyant Aluminum 80 Tank that ST has available. I want to buy a tank of my own and it has my interest (of course, along with some of their other gear ;) )

What I like is that it can be filled to 3300 psi/220 bar, and that you can "take about 3 pounds off your weightbelt if diving this one".

Has anyone got experience with it, and can I have your views/recommendation regarding it?

Regards

Lloyd (Dubai, UAE)

SarahBella
01-07-2008, 06:54
Take a look here...lots of good advice.

http://forum.scubatoys.com/tanks/2335-neutrally-buoyant-aluminum-80-tank.html

I went with a steel tank which was more cash to get, but its also smaller and lighter than a standard AL80. Oh yeah-I can drop 6 lbs off my belt as well.

terrillja
01-07-2008, 08:06
My view- These are a waste of money.

Out of water they weigh more than a normal AL80, and 3 lbs in water is not a huge difference. If you want the same effect, take a piece of webbing, a quick slide, and a lead weight and strap it to the tank. (Use the coated lead, so it doesn't slide)

You will have a lighter tank out of water (with weight removed) and a more adjustable weight in water, all for less then the cost of a AL80N. Also, getting a 3300 psi fill can be a pain in some places, and if the fill operator is not experienced they may not know the difference between the AL80 at 3K and the AL80N at 3300, giving you a short fill.

BSea
01-07-2008, 08:31
My view- These are a waste of money.

Out of water they weigh more than a normal AL80, and 3 lbs in water is not a huge difference. If you want the same effect, take a piece of webbing, a quick slide, and a lead weight and strap it to the tank. (Use the coated lead, so it doesn't slide)

You will have a lighter tank out of water (with weight removed) and a more adjustable weight in water, all for less then the cost of a AL80N. Also, getting a 3300 psi fill can be a pain in some places, and if the fill operator is not experienced they may not know the difference between the AL80 at 3K and the AL80N at 3300, giving you a short fill.

I agree. I think a much better choice is a LP Steel 85. It's just about the same size as a standard AL 80. It may be 3 pounds heavier (1 pound lighter than the neutral 80) but you can take 6 pounds off your belt. And you never have to worry about short fills.

Divingguy
01-07-2008, 09:19
I have one, and I would NOT do it again. I really liked the concept of having a "neutral" tank when empty. However, there are very few places that can or will give me a true 3300 pound fill. If you do NOT get a full 3300 pound fill, your actual air supply is only like 72 - 75 pounds, NOT 80. If you only get a 3000 pound fill, and then wind up with only 2700 pounds when it cools down, you really do get screwed on how much air you have. I won't bore you with the actual calculations, which I believe were discussed in that other thread referred to above. It is a great concept, but it does not work in the real world. Plus, then when you get on dive boats that only use normal AL80's you are constantly having to recalculate or adjust your weight.

ReefHound
01-07-2008, 09:23
I gotta agree, I bought one and regret it. You won't get a 3300 fill unless you watch over the fill guy and remind him, leaving you short of air. I've bought two standard 80's since.

Puffer Fish
01-07-2008, 09:29
I would suggest a HP steel 100... yes it takes a 3440 fill, which can be difficult to get in places, but it is obviously a hp tank... and if they only put 3,000 in it, you still have a 87 cubic ft tank... and every so often, I see them for $249 (with boot and valve)

cheebaweebie
01-07-2008, 11:02
My LDS usually fills my steel 120's up to 3500 which is where the compressor shuts down for saftey reasons. When I pick them up I tell them to top them offf if anything less than 3300. I love the steel tanks. Definately worth the $. You can find tanks for sale all over the place with current vis and hydro for a lot cheaper than you think - steel tanks will last for 60 years if you take care of them. Check out the member items of Spearfishing Planet - Powered by vBulletin (http://www.spearfishingplanet.com) I always see them out there for sale. OR even the member items on this board. You may pay a little extra for the steels even used but you won't regret especially if your looking to drop weight and have a neg or neutral buyoant tank when empty.

cummings66
01-07-2008, 11:04
I agree, the NB 80 tanks are a solution in search of a problem. As I've said in the other thread consider it first. Sure you take 3 lbs off your belt, you know why? Because it's on your back now, and you get the privilege of getting short fills on an AL tank. What kind of joke is that?

My HP100 and HP120's (true HP and not pseudo HP as most newer tanks now are) routinely get short fills. But, they're a good deal because I always have more air than an AL80 tank and that's about it.

I think I like the LP85's as well, weight isn't too bad and I think I could double them up, otherwise I'm in the HP camp.

Grin
01-07-2008, 12:04
Either a LP85 or a HP 100 are great tanks. The HP100s are pretty expensive though. The Lp85 hold 85 at 2600psi. Very often your shop will fill them to 3000 without blinking. 3000 in a Lp85 is around 98cf. And if they do insist on 2600, you still have 85 instead of the 80 a AL80 gets you. LP85 s are usually about $100 cheaper than a HP100. But if you can get HP100s for $250, I'd do that! The problem with HP100s is you ofeten get them back with 3200 or so psi in them. In this case you apid $100 extra to get less than 100. Whereas with the cheaper LP85 you feel good about anything more than 85. Theya r ebotht he same size and have virtually identical weight characteristics. I have a few Lp85s and like them. If I were going to pay the price for HP100s, I'd go ahead and get HP120s. That's what I did anyway. E7 HP120s are about the same size as a AL80(maybe a inch taller).

Lloyd De Jongh
01-08-2008, 00:42
You've sold me on steel, I'll have a look at ST's steel offerings.

Being a recently certified diver I lack the experience and the support of a community of seasoned divers to make sound judgments on some matters, so your advice is much appreciated.

I have to say thank you to everyone, you've cleared up the decision-making for me, and I'll go with the recommendations you've made.

kancho
01-08-2008, 09:22
I would suggest a HP steel 100... yes it takes a 3440 fill, which can be difficult to get in places, but it is obviously a hp tank... and if they only put 3,000 in it, you still have a 87 cubic ft tank... and every so often, I see them for $249 (with boot and valve)

Where? I am looking for a steel tank.. But right now it is out of my price range.

cummings66
01-10-2008, 12:27
You've sold me on steel, I'll have a look at ST's steel offerings.

Being a recently certified diver I lack the experience and the support of a community of seasoned divers to make sound judgments on some matters

I don't know about that. When it comes to diving first rule is use common sense. Second rule is to research the product and see if you have local support or if it's used in your area.

When it comes to tanks the specs are all online and all you've got to do is read them. First realize that air weighs something so the larger the tank the more weight you'll have on your back. Under water weight means nothing, but on the surface it means you've got to carry it.

A tank that's positive when empty will mean you've got to carry lead to offset that and one that's negative means you can subtract a certain amount of lead. What's important to do in either case is to weight yourself to be neutral with an empty tank. That's where you find it takes less lead with "most" steel tanks compared to an AL tank. You can check the buoyancy characteristics of said tanks and see how they do. Some of the LP85's are almost completely neutral empty and other steel tanks can be more than 2 lbs negative. Some AL tanks are positive and others neutral but the way they get neutral is to add weight, in essence instead of you carrying lead on a belt you've got it in the tank itself, but you won't get the benefit of a larger amount of air to breathe because they require a higher fill pressure.

In the end, as my boss used to say, THINK. I believe that will let you make good judgments and use forums to weigh the choices we made.

cheebaweebie
01-10-2008, 12:39
You've sold me on steel, I'll have a look at ST's steel offerings.

Being a recently certified diver I lack the experience and the support of a community of seasoned divers to make sound judgments on some matters, so your advice is much appreciated.

I have to say thank you to everyone, you've cleared up the decision-making for me, and I'll go with the recommendations you've made.


Dive Rite Express sells worthing cylinders if u go new. They ship to your door O2 cleaned valve installed, with boot and valve cap ready to fill.

Shipping was free and you pay no tax I believe. When I bought my 2 cylinders (HP 120's) last year I paid 389 a piece for them I think.

Puffer Fish
01-10-2008, 12:49
What we need is to convince Larry and Joe to have a Worthington sale... with banners and posters... like a carnival....last I checked, they get cheaper the more you buy, as does shipping. I know I would get one...if the price was good. Otherwise, it is back to the competor's, which I really hate doing. If we could get them to see this as a social service, and forget about that profit thing they have... we would all be happier.

terrillja
01-10-2008, 13:53
What we need is to convince Larry and Joe to have a Worthington sale... with banners and posters... like a carnival....last I checked, they get cheaper the more you buy, as does shipping. I know I would get one...if the price was good. Otherwise, it is back to the competor's, which I really hate doing. If we could get them to see this as a social service, and forget about that profit thing they have... we would all be happier.
Sounds like the weezle undergarment sale that one shop does on scubaboard, he gets a bunch of orders together so he can buy in bulk, and everyone saves.

Puffer Fish
01-10-2008, 14:53
What we need is to convince Larry and Joe to have a Worthington sale... with banners and posters... like a carnival....last I checked, they get cheaper the more you buy, as does shipping. I know I would get one...if the price was good. Otherwise, it is back to the competor's, which I really hate doing. If we could get them to see this as a social service, and forget about that profit thing they have... we would all be happier.
Sounds like the weezle undergarment sale that one shop does on scubaboard, he gets a bunch of orders together so he can buy in bulk, and everyone saves.
Exactly... we all agree to buy so many tanks, that even Larry is happy....and then we get a deal. I would not use the Weezle reference though... as it sounds a bit.... humm... under the table.

cummings66
01-10-2008, 17:33
I don't know, I see on AVS Forum lots of group buys. It's a common thing that helps everybody. Now I don't know about the shop selling the Weezle stuff, but I doubt it's illegal. I think ST's could do a promotion deal like this if they wanted to. I know on AVS the way it works is they get a HUGE order together for something, usually more than 100 of them and then they place the order. However AVS is pretty restrictive and normally don't allow advertising on their forums unless it's them or a person buying from them.

Lloyd De Jongh
01-11-2008, 00:05
I don't know about that. When it comes to diving first rule is use common sense. Second rule is to research the product and see if you have local support or if it's used in your area.

When it comes to tanks the specs are all online and all you've got to do is read them. First realize that air weighs something so the larger the tank the more weight you'll have on your back. Under water weight means nothing, but on the surface it means you've got to carry it.

A tank that's positive when empty will mean you've got to carry lead to offset that and one that's negative means you can subtract a certain amount of lead. What's important to do in either case is to weight yourself to be neutral with an empty tank.

That's great advice, I appreciate you sharing. I will keep these points in mind. For now, regarding learning about tank buoyancy and weighting requirements, let me get some experience together with a few tanks and dives before I make the investment. I see there's more to the decision than what I was aware of, which will take some time and experience to discover.

Lloyd De Jongh
01-11-2008, 00:07
Dive Rite Express sells worthing cylinders if u go new. They ship to your door O2 cleaned valve installed, with boot and valve cap ready to fill.

Shipping was free and you pay no tax I believe. When I bought my 2 cylinders (HP 120's) last year I paid 389 a piece for them I think.


Thanks for the info. I'll keep it in mind, however that's a tad out of my budget range right now. Still, it's worth waiting for a while as I gather experience and then investing in good tanks. If I am lucky I may get some 2nd hand tanks somewhere.

RoyN
01-11-2008, 03:17
I currently have 3 AL80N tanks and so far haven't carried any extra three pounds or anything. I'm diving in California using a 7mm wetsuit and my total weight belt is 14 pounds. It could be that I'm packing up some muscles too since I've been working out like Arnold. ;)

P.S. If I had more money, course I would go for steel. But since money is a huge factor is deciding a scuba equipment, this AL80N is the next best thing. Cheers :D

Puffer Fish
01-11-2008, 04:32
I currently have 3 AL80N tanks and so far haven't carried any extra three pounds or anything. I'm diving in California using a 7mm wetsuit and my total weight belt is 14 pounds. It could be that I'm packing up some muscles too since I've been working out like Arnold. ;)

P.S. If I had more money, course I would go for steel. But since money is a huge factor is deciding a scuba equipment, this AL80N is the next best thing. Cheers :D

A neutral aluminum tank just has extra lbs of aluminum built into it, so even though you don't know it, you are. You did get to take off the weight from your belt... but you get the same thing if you just take a standard tank and put some weight on the straps. And that costs less and has the exact same effect

BSea
01-11-2008, 07:42
I currently have 3 AL80N tanks and so far haven't carried any extra three pounds or anything. I'm diving in California using a 7mm wetsuit and my total weight belt is 14 pounds. It could be that I'm packing up some muscles too since I've been working out like Arnold. ;)

P.S. If I had more money, course I would go for steel. But since money is a huge factor is deciding a scuba equipment, this AL80N is the next best thing. Cheers :D
If you look here (http://www.luxfercylinders.com/products/scuba/specifications/us_imperial.shtml), you'll see that the neutral 80 weighs about 4 pounds more & is about 4 pounds less bouyant. So you can see that Puffer Fish is right on the mark. There is no benefit from using neutral 80s. You still carry the same weight, but the difference is that the weight is on your back rather than your belt.

WD8CDH
01-11-2008, 08:50
The only real advantage of the NB AL80 over the regular AL80 is slightly shorter length. In my opinion, it is not enough shorter to justify the added cost.

If you want the most air with the least amount of total weight (Tanks plus weight belt) then the 3442psi steel tanks are the way to go. If you want the most air for the least $$$ then an AL80 is the way to go.

texarkandy
01-11-2008, 08:51
I currently have 3 AL80N tanks and so far haven't carried any extra three pounds or anything. I'm diving in California using a 7mm wetsuit and my total weight belt is 14 pounds. It could be that I'm packing up some muscles too since I've been working out like Arnold. ;)

P.S. If I had more money, course I would go for steel. But since money is a huge factor is deciding a scuba equipment, this AL80N is the next best thing. Cheers :D
If you look here (http://www.luxfercylinders.com/products/scuba/specifications/us_imperial.shtml), you'll see that the neutral 80 weighs about 4 pounds more & is about 4 pounds less bouyant. So you can see that Puffer Fish is right on the mark. There is no benefit from using neutral 80s. You still carry the same weight, but the difference is that the weight is on your back rather than your belt.

RoyN is saying he's neutral with 14 lbs & a NB tank - without the tank he'd need to carry 18 lbs on his belt (or in his integrated BCD) ?

I claim no special expertise or experience, but seems to me there's some benefit for him in getting that extra 4lb's off his weight belt and onto his back - without having to fool around with strapping weights to his tanks or going to the higher expense of steel.

BSea
01-11-2008, 09:22
RoyN is saying he's neutral with 14 lbs & a NB tank - without the tank he'd need to carry 18 lbs on his belt (or in his integrated BCD) ?

I claim no special expertise or experience, but seems to me there's some benefit for him in getting that extra 4lb's off his weight belt and onto his back - without having to fool around with strapping weights to his tanks or going to the higher expense of steel.All things being equal, then yes it would be better to carry the weight on your back than on a belt. But they aren't equal. He'd have saved $100 or more by buying regular AL tanks.

And since he's wearing a belt anyway, I don't see 4 pounds moved from 1 area to another being a $100 difference. Now I do see taking that 4 (or more) pounds off being worth something. That's just 1 benefit from steel over AL.

BTW, once you have the weight pockets on the tank straps, there is no more hassle than to put the weight in the pockets. You don't have to take them off. (Although I would if I were going to warm water where I didn't need them).

Now I'm not suggesting that he get rid of the tanks. There is nothing wrong with what he's diving. But the thread is about someone considering neutral 80s compared to standard 80s. And since the original poster hasn't bought any tanks yet, I was just pointing out that if they you are carrying the same weight overall, then it just isn't worth the extra expense. But that's just my 2.

texarkandy
01-11-2008, 09:56
It's seems to me to be a weight-distribution convenience - We have regular AL-80's here at home

I note my young JOW does a lot better with two pounds of her weight in the trim pockets on the back of her Zena.

Personally I'd wish I'd gotten the trim pockets on my Brigade so I could pack about 4 pounds of my 12 or 14 (depending) back there. I wonder how much the trim pockets are gonna set me back as opposed to if I'd bought an NB tank.

(on the other hand - when on a trip & using rental AL80's I guess I might be better off getting some trim pockets for my BCD to accomplish the desired weight distribution - or strap em on with a homemade rig)

Am curious - is the extra 4lbs in the NB in the bottom? Or all over?

cummings66
01-11-2008, 10:38
It's on the bottom is what I was told.

RoyN
01-11-2008, 14:03
The AL80N tanks were only $25 dollars more then the normal AL80 tanks. :D

cummings66
01-11-2008, 16:22
Yup, for the 80 it works out that way. Still I would have chosen a different tank because you've got to get 3300 psi in order to have a full fill, and in my neck of the woods that's not always possible. The lower pressure AL80 almost always gets a full fill and thus more air.

RoyN
01-11-2008, 17:19
What do you mean more air...? :smiley5:

terrillja
01-11-2008, 17:22
What do you mean more air...? :smiley5:
The 77(true)cf on a neutral assumes a fill pressure for 3300psi, if you only can get fills to 3000psi, you will get more air in a regular al80, since it is filled to its capacity.

RoyN
01-11-2008, 19:17
Oh well...I usually come back to the boat or shore with 600 to 1000 psi and my average bottom time is from 40 to 50 minutes. Anyways, kudos and cheers to everybody here! :smiley20: :smiley32:

Puffer Fish
01-11-2008, 20:30
Oh well...I usually come back to the boat or shore with 600 to 1000 psi and my average bottom time is from 40 to 50 minutes. Anyways, kudos and cheers to everybody here! :smiley20: :smiley32:
Hey Roy... most of us don't like that tank because of the combination of it's smaller size and the extra weight. But if the tank is the right size for you...and the price was right.. then it was a great decision. The one thing that tank has over every other one out there... is it is yours...heck, I normally dive with 117 cubic ft tanks...which weigh a lot more than that tank you have.

Lloyd De Jongh
01-12-2008, 05:29
[quote=texarkandy;118700]... [snip]... But the thread is about someone considering neutral 80s compared to standard 80s. And since the original poster hasn't bought any tanks yet, I was just pointing out that if they you are carrying the same weight overall, then it just isn't worth the extra expense. But that's just my 2.

I've learned a lot about the pros and cons here so far, and there are a fair number of angles to look at before you get a full picture.

I have to agree, carrying the same weight overall isn't worth the extra expense. No point in shifting it from the belt to the tank.

cummings66
01-12-2008, 10:53
When it comes to tanks, two things matter. The price and the buoyancy characteristics when empty.