Steel 72 questions

[Wheatondiver]

How do steel 72's compare to aluminum 80's?

Surfing a LDS' website and noticed used steel 72's. Hydo 8/07 and 9/07. value guaranteed for 30 days. I do not know how old the tanks are. One is consignment. The other one does not indicate. They are listed for $75. There are some others, but the hydro dates are 11/06 adn 12/05.

Would these be a good deal?

 

[spectrum]

I would assume that there is a fresh VIP on there as well. If that's the case and you back out the new value..
Hydro $20
VIP $15
Fill $4

You are paying $36 for the used tank and virtually all of the risk has been mitigated. We can quibble about the values I chose for the services but I'd say that with any sort of warranty at all it's a decent price. Folks are more accustomed to paying close to $20 for these tanks but they are usually in need of testing and are bought with the risk of not passing.

Even with a year or 2 off the hydro it's not a bad deal if they are in nice shape and what you want.

Pete

 

[JohnW]

72's are a great value. I own 7 of them(2 Doubles and 3 Singles) $75 is about the going rate up here in Canada. Plus the weight shift is insignificant during the dive and trim is better than with aluminum tanks. AS spectrum mention your reallly only paying $36 for used tanks, if I was within driving distance, I'd own them.

 

[spectrum]

Plus the weight shift is insignificant during the dive

Hold the phone here.....
Weight shift is only relevant to the amount of air you use. Other than sheer volume it is not a cylinder property.

Wheatondiver

Remember that it is only a 72 when overfilled by 10%. For that to happen the last Hydro date needs to have the + symbol appended. Otherwise it should only be filled to the rated 2400 PSI and will contain about 65 CF.

Pete

 

[fweber]

If they aren't plus rated at their last hydro and you have an anal fill station that will only fill them to the base rated 2250, you end up with steel 65's. Many places just mindlessly fill them to 3000 without looking. I own a total of 12 72's at this point(4 sets of doubles, 2 for O2, and 2 random spares). So, yes, I like them. As already stated, generally a couple pounds lighter on average than al80's, neutral or close to it when empty, both add up to a lighter overall rig, 6-7 lbs per single. The price doesn't sound unreasonable.

 

[fweber]

Hold the phone here.....


Remember that it is only a 72 when overfilled by 10%. For that to happen the last Hydro date needs to have the + symbol appended. Otherwise it should only be filled to the rated 2400 PSI and will contain about 65 CF.

Pete

Better put that phone down...... don't be spreading misinformation. Older steel 72's are base rated to 2250 and with the plus qualify for 2475. So, 65 cf at 2250, 72(actually 71.??) at 2475, and around 85 at 3000 (if the filler doesn't notice that they aren't 3000psi cylinders).

 

[spectrum]

Better put that phone down...... don't be spreading misinformation. Older steel 72's are base rated to 2250 and with the plus qualify for 2475. So, 65 cf at 2250, 72(actually 71.??) at 2475, and around 85 at 3000 (if the filler doesn't notice that they aren't 3000psi cylinders).

Good call, there are variants in LP over the years.

The point stands that if it does not have the + symbol he is getting something much closer to 65 CF.

 

[Luis H]

IMHO, if they are galvanized, they are great tanks.
I own 11 steel 72 (one has a 1/2" straight pipe thread Sportways valve, all the other are conventional 3/4" straight pipe thread). They are basically my favorite tank.

That being said I personally would not touch a tank that is not galvanized and probably would not touch it if it had a 1/2" pipe thread neck.

I hate rust and IMHO all other finishes other than galvanized will allow rust to travel under the finish.

The 1/2" neck valve is a pain to VIP and clean/ tumble the tank if it is ever needed. Even if you pay to have the work done, they won't do as good of a job. Therefore, I would not touch a steel tank with a 1/2" unless I saw the inside was very clean and it came with a good valve, and even then it would be my last choice.

If the tank is a 3AA with a working pressure of 2250 psi, the original date on the tank is irrelevant. This tanks can last your life time, if they are not damaged by rust or fire.

I would ask to see the inside myself. Even if you have never done a VIP ask them to show it to you and describe what you are looking for. Hopefully they would not charge you, but it may be an extra $10 or $15. The education alone I think would be worth it and you get to check that the tank is actually clean. This is optional if you really trust the dive shop you are dealing with.

 

[Jim Lapenta]

I am another fan of steel 72's. I have 4. One set of doubles and 2 singles. The original dates on two of em are from the 50's. Still passed 6 months ago. I routinely fill mine to 2800-3000. Trim and weight are excellent. Where exactly is wheaton Md. I'm in sw pa and what shop did you see these at. It'd be worth a 2 hour or so drive to me this weekend to get a couple more for another doubles set up at that price.

 

[Danny D]

Agree with everyone that 72s are great tanks to dive. Currently own 4 with two doubled as an original set. I also take the same position as Luis on the 1/2'' necks. My doubled set is from 58 with ½ necks and they are a pain every year to get a VIP and then reassemble the manifold so they do not from the tank necks. Stick with the ¾ ‘’ throats and you will be very happy!