Question, vintage LP72 tank

[rnln]

Hi,
If it passes hydro, it would be fine. I have a few of these (metric 10L in fact) and they don't look "nice" but it is the inside that matters.
You are not going to get much by selling it. So remove the valve, have a look inside and see how it is. Even if it has rust, it is removable. A steel tanks from this period would last longer than a new alu tank.
I heard that hydro in your part of the world is quite cheap, so sent it to test; it is a cheap bet

Thanks everyone.

Jale,
If I take a look inside, do I have to give it some compress air right away, or it's still good to leave it empty for a little while, let say a week or two?

Couv,
So the different is only around 2 or 3 mins more on the Al80, if I can get the LP72 a +.
The air in there is 20 year old. I honestly don't want to breath it before hydro/VIP.

Looks like the decision is to keep it. Thanks everyone again.

 

[2airishuman]

Thanks everyonso Ie for your opinions. Another decision question, if you are given between this LP72 and an AL80 in current hydro (fairly new), which would you choose?
Thanks again.

Hi rnln

I like LP72s and presently have about 10 of them, all galvanized, all either Norris or PST.

Yours is a Norris but it is painted, not galvanized.

Typically I will pay $30 for a galvanized Norris or PST LP72 that is out of hydro and with an older valve. It costs me $55 to revalve them and around $20 for hydro which brings my acquisition cost to $105 if everything goes smoothly. I allow for a 10% hydro failure rate on as-found cylinders and add some cost of driving around to sellers and hydro shops, so I figure the cost of a ready-to-go LP72 that is in hydro with a new valve, full of air in my garage, is around $125-$150.

Typically I don't buy painted cylinders because the extra cost of sandblasting them and painting them is more than the as-found cost of a galvanized cylinder.

I have sold all the painted LP72s that I ended up buying as part of a mixed lot with galvanized LP72s.

I have a slight preference for LP72s over AL80s mainly because they result in a slightly lighter overall kit (less lead) but in reality they are largely interchangeable; there is a noticeable practical difference between diving an AL80 and an HP100 but not between an AL80 and an LP72 on a real-world dive (aside from interpreting the SPG a little differently)

A fact to consider is that in Florida there are quite a few shops that won't fill LP72s for various reasons.

Prices do vary regionally. In Florida (among other places) there are so many divers and so many dive shops that the shops by AL80s by the pallet and sell them at much lower prices than dive shops in, for example, Minnesota. In areas where AL80s are cheap there is no financial benefit in performing CPR on an as-found LP72.

 

[jale]

Thanks everyone.

Jale,
If I take a look inside, do I have to give it some compress air right away, or it's still good to leave it empty for a little while, let say a week or two?

Couv,
So the different is only around 2 or 3 mins more on the Al80, if I can get the LP72 a +.
The air in there is 20 year old. I honestly don't want to breath it before hydro/VIP.

Looks like the decision is to keep it. Thanks everyone again.

Once empty, you can leave it empty. Just rescrew the valve (hand tight is enough).

 

[rnln]

Thanks everyone, I pulled the stamp and start tuning my regulators tonight. It works awesome. Now, I owe a tank, a vintage tank . Thanks again.

 

[Lostdiver71]

Triple yeah. Especially as you already own it. But why not dive it, rent an Al 80 and judge for yourself?

Here is my take on the 72 vs the Al80 (I'm going off memory, so I welcome any corrections.)
The 80 only holds about 6 cu feet more than a 72 ( 77 vs 71)
The 80 weighs more than a 72-about 31 lbs vs 29 lbs
The 80 is positively buoyant at the end of a dive-about 4 lbs compared to a neutral 72. Therefore, you are swimming with 6 more pounds of mass (not to mention carrying it to and from the car and the boat or shore) for a measly 6 cu ft of gas. So some of the extra gas will be used up just from having to swim with more mass. Speaking of swimming, for me the 72 just "swims" better-but I'm only 5'8" and on the well-fed side.

Remember, unless it is + rated on the Hydro, a 72 only hold 65 cubic feet of air! If it is + rated it will then hold 71.2 cubic feet. I have four of them and two are going to become a small set of doubles once I can find the right set of bands to work with my manifold.

 

[Jcp2]

Hard to get the + on hydro these days.

 

[lowviz]

Hard to get the + on hydro these days.

Pointless to search hydro facilities, you can do even better than that with a standard hydro. You just need a shop that understands those tanks.

I can get 3K from several shops as long as they know the background of these 72's and have a VIP that they can trust. Not so sure about ungalvanized, just don't know. But a 2800 fill seems entirely reasonable for that tank. ***Internet Advice***

72cuft at 10% overfill: So they are really 72-7.2cuft = 64.8cuft at rated pressure (2250).

64.8*(2800/2250) = 80.6cuft

 

[Jcp2]

I understand your point. It’s like a vintage cave fill. But around here, only people with their own compressors have that luxury, as we have few shops and no caves.

 

[Couv]

Hard to get the + on hydro these days.

Perhaps where you live, but not a problem here. In fact the manager of the hydro facility I use, used to post here on SB. It's best to touch base with a hydro facility before bringing in a steel that you want a + applied.

 

[rnln]

I contacted multiple places, include those fire protection, some don't do + rating. Some will do but need official REE but no one has it REE for Noris