Aluminum 72 (AL72): what to do with it?

[rhwestfall]

The bottoms make great dog bowls. I saw one made into a mailbox. BTW - Aluminum makes crappy bells... Crowns make great regulator display stands... BBQ grill? Wine bottle chiller...

 

[LFMarm]

Great for sidemount dives that do not require a ton of gas

 

[formernuke]

Great for sidemount dives that do not require a ton of gas

Those tanks require yearly hydro and Eddy testing. Around here I was told around 200 dollars each time. So 200 a year just to make them "legal" to fill. Some shops still won't fill them.

 

[NW Dive Dawg]

What about using them as an emergency surface O2 supply.......along with a 100% cleaned reg set and a RescuEAN. The 2400 PSI capacity would get you the full 72cf which is more than triple a DAN Jumbo D bottle.

 

[formernuke]

What about using them as an emergency surface O2 supply.......along with a 100% cleaned reg set and a RescuEAN. The 2400 PSI capacity would get you the full 72cf which is more than triple a DAN Jumbo D bottle.

Again the annual testing on them, at least around here is close to cost of a new tank. Even with that some shops won't fill them no matter what testing is done.

 

[-JD-]

Those tanks require yearly hydro and Eddy testing. Around here I was told around 200 dollars each time. So 200 a year just to make them "legal" to fill. Some shops still won't fill them.

I have never heard of annual hydro requirements (in the US). Eddy inspection is required at the 5 year hydro and effectively at the annual inspection.
From: A short Review of 6351 Alloy Aluminum Cylinders

The US DOT has, in CFR 49 Title 180.209 m requires that all 6351 T-6 alloy cylinders in SCUBA, SCBA and oxygen service be examined at time of hydro requalification with an eddy current instrument. Cylinder manufacturers recommend (thus essentially require) pertinent cylinders be eddy current tested at time of the visual inspection conducted on SCUBA service cylinders.

For $200 a pop, they better be, hydro'd, VE'd, VIP'd, mirror-polished inside and out, O2-cleaned, and filled with 100% He. Obviously not worth it at the shops you have talked to.

Again the annual testing on them, at least around here is close to cost of a new tank. Even with that some shops won't fill them no matter what testing is done.

How frequently are you refilling your emergency O2 bottles?

All said, it may not be worth it unless they can be filled privately.

 

[tmassey]

Spit-ballin' ... Bundle them together with your steel stages for a more neutral package?

You can’t do that. Because the bottles are separable, you actually have to think about what would happen if you lost one or the other. In other words, you have to be able to handle the loss of either your heavy tank or your floaty tank. That means you need to be even more overweighted, plus the heavy steel tanks, plus the extra demands on your wing lift requirements. In other words, not a good idea. (Though I appreciate the out-of-the-box thinking!)


Wow. Crazy. Universal clear statements that these tanks aren’t worth even a few dollars for a hydro. Disappointing. Not because of cost: there is enough value in scrapping them. But just because there’s no value to utilize these for the task for which they were intended.

In the US, there is only a five year requirement for Hydro, even for these tanks. The visual eddy does add a few dollars, but I think it’s under $40 total — but that’s because I don’t have it done at a scuba shop.

There is room in my life for a portable emergency O2 bottle bigger than an AL40. But an old AL80 could do that just as well, and has a lot more value in a lot more places.

Sigh. I’m still holding out hope, but it’s fading fast…

 

[-JD-]

You can’t do that. Because the bottles are separable, you actually have to think about what would happen if you lost one or the other. In other words, you have to be able to handle the loss of either your heavy tank or your floaty tank. That means you need to be even more overweighted, plus the heavy steel tanks, plus the extra demands on your overall buoyancy. In other words, not a good idea. (Though I appreciate the out-of-the-box thinking!)

Well, a twinset is seperable under the right or (wrong) circumstances and you haven't seen ME bundle things. But point taken.
Baaaaahhhh - BURN the box! Single-outlet manifolded doubles configuration.

 

[formernuke]

I have never heard of annual hydro requirements (in the US). Eddy inspection is required at the 5 year hydro and effectively at the annual inspection.
From: A short Review of 6351 Alloy Aluminum Cylinders


For $200 a pop, they better be, hydro'd, VE'd, VIP'd, mirror-polished inside and out, O2-cleaned, and filled with 100% He. Obviously not worth it at the shops you have talked to.


How frequently are you refilling your emergency O2 bottles?

All said, it may not be worth it unless they can be filled privately.

Could be the one local shop that might fill them if the above are done annually. Others here won't touch them no matter what.

As for O2, emergency O2 is on the boat/shore. The O2 I carry in the water is for deco and gets used when I do deco dives.

 

[macado]

I'm unfamiliar with the older AL72 varieties but the newer AL72 3000psi tanks actually make excellent stage bottles and bailouts. In fact I prefer them over AL80s. They ride much nicer and like AL40s to me.

Unfortunately it sounds like the old ones might be super floaty and 6351 alloy as you said? I agree with others, I'd maybe use them as a surface emergency O2 bottle, dedicated low pressure tire/balloon filler or unfortunately scrap them. As much as I hate throwing things away myself I just dont find 6351 alloy tanks worth the hassle, even with my own fill station.

We all know the risk is minor and and with proper Visual Eddy (VE) testing they are perfectly legal but most shops in my neck of the woods still won't touch them with a 10 foot pole.

My other thought: Maybe donate them as cave project safety bottles? I honestly dont know if there is value there. For those unfamiliar with I am saying, these tanks are used in cave exploration projects and stay in caves underwater for extended periods of time. After 6-12 months underwater even with an anode they're mostly disposible and end up being trashed.