My urge to own a steel tank ...

[lowviz]

Why specifically steel? -weight or stress-strain characteristics?

Buy a copy of Vance Harlow's Oxygen Hackers Companion. Chapter 7 "Tanks and Valves". Page 84. (Nothing to do with oxygen for this issue) Quoting:

"Note that all the discussion above is about STEEL tanks. Aluminum tanks, it cannot be overemphasized, handle stress very differently than steel, and absolutely CANNOT be overfilled in the same extravagant fashion as some divers overfill steel tanks."

The book explains this.

Bottom line: I like to buy new aluminum and vintage steel...

 

[TSandM]

I think the biggest advantage of owning your own tanks is the ability to go diving at a moment's notice. If all of your diving has to be massively pre-planned, you may not save much, if any money by owning your own. Our local shop charges $10 for a tank rental, and $10 for a fill (don't ask me to explain this) so one is better off renting their tanks, and not having responsibility for a yearly viz and q5y hydro.

The only other advantage I can think of is if the only tanks you can rent where you go are either small, or the wrong material. For example, if you're diving in Maine and can only rent Al80s, you might prefer to own steels. In West Palm, the general rental tanks were Al80s, so we dove doubles.

 

[USFpsychDiver]

I'm still waiting on buying tanks. If I'd bought when I started I would have gotten AL 80s. Now I rent steel 100s when I have the chance, but they're harder to come by in retal inventory and cast more to rent. I'm also switching regulators from yoke to din. So what I'd buy has changed. With about 30 dives on rented tanks over the past 10 months thats roughly $60 for tank rental. If id gotten a used AL80 for $60 (not that hard to do) I'id be even on cash but would have the tank. I'm also gearing up for doubles and there's a bewildering array of tank size/pressure options all with different characteristics, so I'm hoping to try a few before buying. In the mean time I keep my eyes open for a good deal on used steel tanks; the do show up with some regularity. I'd probably snag a pair of HP 100s if they showed up used at the right price.

 

[CAPTAIN SINBAD]

Why specifically steel? -weight or stress-strain characteristics?

Because I tried cold water diving with AL-80s and it was not fun. The weight that was needed to sink was a bit too much and a lot of that can be removed if the tanks and Back plate is steel.

 

[DA Aquamaster]

In line with what Lynn has said, divers who own their own tanks tend to dive more. It might have overtones of the "I own it, so I better use it" effect, but it probably has a lot more to do with convenience. If you own your own, you just pack the car and go diving and get fills on the way home to be cocked and locked for the next time you get the urge to dive.

The economics of tank ownership is a separate issue. A big part of it is the cost of VIPs (pretty minimal most places - no one makes money on a VIP) but more importantly hydro tests every five years.

A business pays somewhere around $7-15 per hydro, based on volume, but shops usually double that and pass it on to the customer. A $15 hydro is very reasonabl (maybe $30 with VIP and fill added on top) but a $30 hydro and then another $15-$20 for a VIP and fill starts to add up if you have several tanks. But then again, spread over 5 years it's still less than $10 per year per tank.

O2 cleaning is the elephant in the closet at that will cost you about $50 per tank and is an annual expense, but it's only needed in most locations if you get nitrox via partial pressure blending. If no part of the tank or valves ever sees O2 percentages over 40% O2 cleaning is probably not needed, but some areas (Northern VA, for example) require O2 cleaning for any tank that is filled with nitrox by any method.

So whether rental versus ownership makes economic sense depends in large part on what the maintence costs will be in your particular area.

 

[grantwiscour]

I bought some tanks last year and have been very happy with the decision. We started diving in places where there weren't any dive shops close by. Owning our own tanks make it easy to show up at some water and jump in.

 

[CAPTAIN SINBAD]

DA Aquamaster: If I am understanding your post correctly, a tanks ownership means spending 50 USD on O2 cleaning if it has been used for Nitrox? Thus two tanks dedicated to nitrox usage would mean 100 USD a year. I mean if the tanks are dedicated air tanks then they will only require visuals and a hydroinspection every five years? Just wanted to add the correct math to see if it would make my life easier.

 

[James R]

You need VIP every year and hydro every 5. You will need to 02 clean them if where you fill them with Nitrox does partial pressure blending.

 

[Colliam7]

DA Aquamaster: If I am understanding your post correctly, a tanks ownership means spending 50 USD on O2 cleaning if it has been used for Nitrox?

No. What DA was referring to was having them O2 cleaned for use with richer blends, or nitrox blends where partial pressure blending is required, or for having them filled by some (uncommon) fill operations that might require O2 cleaning for any tanks in which you use nitrox. That would not be the usual and customary case for using them for nitrox, by any means. And, for the recreational diver, seldom do you have tanks oxygen cleaned. i would not base a tank buying decision on that as a possible additional expense.

 

[Colliam7]

I am thinking what I should do about my urge to own a couple of steel tanks! I live in DC area and there is no ocean nearby. This season I plan on diving North Carolina, MA (Cape Ann), Maine and the Great Lakes. These along with Florida coast will be areas that I see myself diving most frequently. . . . Does it make sense to own your tanks specially if you wont be diving every weekend? Can anyone tell me what are the hassles involved in owning your own tanks and whether it makes sense to consider it.

As several have said, tank ownership is reasonable, it may encourage you to dive more, and you have a number of options - new vs used, steel vs AL, HP vs LP, etc. I can't say that you can 'justify' it on a pure $$ and cents basis, but if you are going to dive 10 weekends out of 52 (just to pick a number), for example I would go for it. The hassles are few - the 'cost' beyond acquisition cost, is the annual visual inspection, and the every 5 years hydro, plus the costs of filling.

Lots of threads on SB about tank material (AL vs steel), working pressure (HP vs LP), volume, etc. I think you idea of steel because you are diving in cold water, in salt water, is very apppropriate. If you can find used steel tanks, they are probably worth considering. A 'warranty' is not an issue with tanks as much as whether they have a current hydro when you buy them. I won't even open the door on tank size, but would suggest you do a SB search - perhaps start with 'tank size', or even 'HP100', which should open the floodgates of available information.

Probably the last thing I would worry about at you level right now is the expense of oxygen cleaning - you don't need it. Buy a couple of tanks - if you are going to buy one, you need to buy two. Dive them, with air, get used to their trim characteristics, your weighting requirements with them, enjoy developing your dive skills by diving more