My little twin 72s

[canuckdiver]

BTW, it wasn't me, I have mine already!

 

[boomx5]

Does anybody know where I can get a set of tank bands for a set of steel 72's?

 

[O-ring]

Cheap too...I have them on my 72s..

http://members.aol.com/mrdeco/page/index5.htm

 

[boomx5]

Those will work great on my new set of 72's.:mean:

 

[scubatexastony]

lal7176 once bubbled...


I would also think that the double 72's are more negatively buoyant than my single faber LP 95(+2lbs empty). Any idea what the buoyancy characteristcs of the double 72's are?

Well, I didn't know off hand, other than I don't add a V-weight or any other weight when diving wet with 3/3. The tech dept. at Aqualung responded with this:

"I don't have the exact numbers, but the catalog copy claims that they should be neutrally buoyant when empty.

Regards,

Jim"

and I was guessing they were about 10 or so full, so I wasn't far off.

tony

 

[pescador775]

These tanks were the standard for many years being a stretch version of the aviator oxygen tank otherwise known as a '38. The original PST tank was a 70 @ 2150+ later upgraded to 2250+. US Divers used a 1/2" taper thread until 1963 when they adopted the 3/4 thread pioneered by Sportsways. Healthways was one of the last to give up the 1/2 inch thread. For a while they experimented with 5/8" O ring but abandoned that idea quickly.

Many things to be cautious of here. US Divers, for many years, but particularly around the late 60's sold a yellow painted tank that would rust up quickly. Also, during the early to late 60's some Dacor and USD tanks had an internal epoxy coating that would blister, trap water and rust. It is impossible to tumble some of these but not all. It was during the mid 60's that the internal coatings were thickened to the point that a rust spot would automatically condemn one of these tanks. Coatings were discontinued in the mid 70's. My advice is not to purchase ANY internally coated 72. For external finish buy only galvanized.

Twin 72's have near perfect buoyancy characteristics in salt water. They are slightly negative in fresh water. Manifolds and bands are commonly available for these 6.9" dia tanks. I recommend them for general SCUBA diving except beach dives where a single 72 might be more appropriate. Also, my experience is that twin 90's are more suitable for certain dives such as a two dive, open water, no decompression plan.

 

[sheck33]

Uncle Pug once bubbled...
I put together a set of steel 72s a couple of weeks ago and I just love them! They are sooo light and trim out perfectly.

For single tank rec dives I had borrowed a couple of LP104s from a friend (all of ours are doubled up and filled with mix.)

Then, since I had a some lp steel 72s that were not being used for argon I started diving them as singles.

Then I decided to go ahead and double them up.

Well they are just sweet! I have a 10# V weight between them and that is more than enough total weight with the 6# SS backplate.

Today I will dive them that way and Friday I will take the V weight off and dive with an 8# belt just to see which I prefer.

But the best part is this:

Yesterday I only filled them to 1500psi since I wanted to get them down to 500psi at the end of the dive to play around with weighting.

We did a 52 minute dive (max 128') and I was able to get them to 500psi (down to 450psi by the time I finished playing with the weights.)

I can do two dives with these little guys filled to 2500. But better yet... I can still do one dive even if my nitrox bank is down to 1500psi.

Using the single LP104s I always refilled the bank when the highest bottle got down to 2500 psi.

Since the 3 cylinder nitrox bank is at 3700psi when full... that means far fewer compressor starts per month.

I'm really happy with these little guys.

I love 'm too, i will use my double 72's until i can afford double 104's. They are fairly light and balance perfectly.
You can find PLENTY of 72's on Ebay.

 

[Waterborne]

lal7176 once bubbled...
Thats cool. I thought i would need a special manifold and valves.

What do you guys think of a couple of these.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=16057&item=3606504626&rd=1

I think they are 72's

Did you guys catch that sellers disclaimer?

PLEASE HAVE ALL AND ANY DIVE EQUIPMENT CHECKED BY A PROFESSIONAL IF YOU DONT DO THIS IT MAY RESULT ~DEATH~ OR WORSE

It gets worse than death???

 

[omar]

I have been diving double LP80's for a couple of years and love em. They get more use than the 104's. I also prefer them to double AL80's. I use a 5 lb P-weight with 6lbs on a belt ( I always have some ditchable weight). I pump them up when I wwant to get some extendeed dive time off of them as well.

omar

 

[Dryglove]

scubatexastony once bubbled...
When I put em on the scale at the LDS..



mine weighed 48 lbs with manifold, bands, and empty.

Is this for steel 72's? I am curious as a few places i emailed selling used ones say they weigh right at about 30-33lbs each empty. If they do weigh in at 48lbs doubled up i will be extremely happy. I just closed a deal for a set but forgot to ask the weight.