first set of doubles for apprentice cave

[Doc Intrepid]

excellent... thank you all

Hey Andy,

Speaking as someone who did what you're doing...DiveSherpa was right on regarding the PST 80s. They are sweet tanks, and not pig heavy like the larger steels.

About the yoke to DIN adaptors - some are better than others. It depends on the regs you have, but some of the DIN adapters add nearly an inch or more to how far the 1st stage sticks out from the valve. Huge PITA. I have both 200 and 300 manifolds, and both work okay. If you're planning on using yoke regs, keep a 200 manifold. But I suggest you get a good look at what that DIN adapter is going to do to your regs 1st stage (in terms of overall profile). You may be better off putting your yoke regs on ebay and picking up a couple DIN regs from the same source.

FWIW. YMMV.

 

[OneBrightGator]

I'll echo the other statements that PST LP80s or Faber 85s would be the best option for you. The difference in manifold is negible, if you do something to damage a 200 bar connection it'll probably be enough to damage a 300 bar one, also keep in mind 300 bar manifolds can't be used with yoke regs (not that I'm recommending you use yoke regs).

 

[mweitz]

Just out of curiosity, why not E7-100's instead of the 80's?

Mark

 

[Divesherpa]

I guess they are about the same thing. I only have LP 80's, so I can't comment on the other bottles.

Of all the tanks that you see for sale, do you ever see a pair of LP 80's?






Nor will you!!

 

[charlieo]

Andy,
You can rent various double sizes at Cave Excursions or Dive Outpost. Spend some time with them (and a buddy) in open water at one of the springs in that area. You would then have some experience with the different sizes and could make your selection based upon that experience.
Don't try to take Apprentice without some practice in steel doubles. I did that. BAD plan.

 

[H2Andy]

that's a good idea, renting first... very nice

 

[Tom Winters]

When you get your doubles, walk around in them and build up your back muscles - SLOWLY. Work up to twists and bends to let your back and the tanks become close personal friends. I can see the twin 95's for cave stuff, although I dearly love the twinned 85's. They're 7" in diameter and lighter than a pair of 80 aluminums.
I'm not wild about the DIN-to-yoke adapters, although they're a necessary evil while traveling. Once you get one DIN valve fitting, you're going to start looking suspiciously at your yoke valves and trying to justify changing them over.
All of my regs are 232-bar. They should probably be 300-bar since I love overpumping my tanks. I try to hold the limit at 3600 psi though.
But work those tanks on your back - take a few months. When you're humping your cave gear down some miserable trail, your back will thank you by letting you get up the next day.

 

[triton94949]

that's a good idea, renting first... very nice

Exactly.

PST E series advertises that their 80s are "nice and short." That however is not great for doubles. Longer thinner tanks are better than shorter ones, in my experience, when doubled.

The older steel LP 72s were perfect for this, for shallower deco applications (shallow = 6.5 ATAs or less).

Therefore although I agree that the PST E Series 80s are perfect as single tanks, I don't believe they would be very good as doubles, unless you are a very very short person.

Renting will help you experience several designs and decide for yourself.

My pat answer would be two sets of twin E Series 130s, and two sets of twin 72s, and three single E Series 80s. But that is just me.

Regarding din or yoke, I think you will soon be graduating completely away from yoke and exclusively onto din. You will need one yoke adapter for your din regs on non-tech boat dives. Beyond that, I am sure you will forget about yoke.

 

[blibecap]

What brand of regs do you have? I second for renting but LP is the way to go and the OMS 85's are nice but small.

 

[charlieo]

When you get your doubles, walk around in them and build up your back muscles - SLOWLY. Work up to twists and bends to let your back and the tanks become close personal friends.
Tom,
I'll never be friends with my big steel tanks. I've learned to live with them. I was cave diving in Mexico a few months ago. Double AL 80's. OMG! Relax. Easy to dive but not the capacity of steels, didn't need it.
We use those big steels because we have to. Learn to use them, become comfortable with them. You don't have to like them.
Don't want to start a Peeing contest here over tanks. But I would like to know what other feel about the problems using steels.