Bands & Manifold for Rental Tanks?

[metridium]

Originally posted by Uncle Pug
If you can afford to get into tech diving then you can afford to get into it right. Each set of doubles will have its own bands and its own manifold specifically sized for it and you won't be trying to cobble stuff together.

That's pretty much what I had expected from the dive shop guy, so it was a surprise to hear that one particular Dive-Rite set should work for both the 80s and 72s. This wasn't a LDS monkey, either....but rather a manager of one of the best-known tech dive shops in the US, and a technical diver himself.

Originally posted by Uncle Pug
Use your planning and situational awareness skills to make up for dunces as buddies... or just refuse to dive with the putz... but don't be the guy that everyone else whispers about.

On a boatload of people using force fins, spare air, etc., I should be concerned what others think of my gear? On one particular liveaboard I've done several times, I've never seen another diver using a backplate or a long hose. So should I ditch those, too?

Originally posted by Uncle Pug
Boat dives with a drysuit?? Is this cold water??? Why not go ahead and buy a couple of 104s and dive them as singles. This will give you an idea of what life is going to be like when you double them up.... and maybe get you into shape for it. We have some HP steel fans on the board and I'm sure that they would advise you to go that way.... maybe a hp 120!

1. I've been diving 95s for several years now; data for the 104s seems only incrementally different.
2. This is for travel, not driving-distance diving. Shipping 104s (or any other tanks) cross-country and back several times a year isn't feasible.
3. HP is a poor choice if 3000 psi is the upper limit for a boat's compressor. Not to mention the buoyancy characteristics vs. LP.

Originally posted by Uncle Pug
But why steel 72s??? I have some that I use for argon storage and I have dreamed of doubling up a set... but then I wake up... why??

Because at one of my favorite destinations, the only two steel tanks commonly available are 72s and 95s. I normally dive the 95s, but doubling them would be tremendous overkill. AL is not an option because of the drysuit.

Originally posted by Uncle Pug
Regulator failure on properly maintain equipment??? That's a rarity I'd like to hear more about.

Sudden first-stage swivel failure just prior to a dive. Regs were due for annuals in a couple of months, had been well-maintained and cleaned in the months since last service, standard reg usage/removal/storage protocols were followed stringently. Somehow a salt crystal or two found its way in there, apparently, where it wrecked the spacers and an o-ring or two.

 

[Uncle Pug]

Originally posted by metridium
surprise to hear that one particular Dive-Rite set should work for both the 80s and 72s.

I've never seen another diver using a backplate or a long hose. So should I ditch those, too?

1. I've been diving 95s for several years now; data for the 104s seems only incrementally different.
2. This is for travel, not driving-distance diving. Shipping 104s (or any other tanks) cross-country and back several times a year isn't feasible.
3. HP is a poor choice if 3000 psi is the upper limit for a boat's compressor. Not to mention the buoyancy characteristics vs. LP.


Because at one of my favorite destinations, the only two steel tanks commonly available are 72s and 95s.

Sudden first-stage swivel failure just prior to a dive.

(I shouldn't post so late at night - I sounded way too cranky)

Hi again metridium,

Like Roak says the bands space the center of the cylinders.. right bands for each tank and you can use the same manifold.

No... not at all suggesting that you should ditch your BP/Wing Long hose.... just suggesting that double steels might be overkill afor a rec. travel dive... but if that is the tool you need then that is the tool to use... for example we are traveling (by truck) to Canada in a couple of weeks and Shane and I will take our double 104s with a trimix in them.... but we are also going to take steel singles and use them for most of the dives. If the place we were going to had 95s I would probably use them.

BTW the difference between a 95/104 might not seem like much but it can be enough to help your trim if you are a taller guy. And no I wouldn't suggest them for travel tanks ;-)

As for the regulator failure...
It was on the surface... but if it had failed on a dive would you not have had plenty of time to do a safe ascent??? If you were diving singles and took along and extra regulator you could just swap it out at the surface and continue diving.... but if that extra regulator is part of a twinset then what do you do other than sit out the days diving?

I am not convinced that twin tank diving is better for the standard recreational reef dive. And it definitely complicates logistics!

 

[Lost Yooper]

Metridium,

I think I understand what you want to do -- you want to start training for tech stuff, right. I think it's a good idea to do several recreational dives with doubles before you jump into a cave or a deep dive. I'm not sure that assembling doubles on a rec diving vacation is all that practical though.

If you're concerned about first stage failure (which I wouldn't beon a warm rec dive), then maybe get a couple H-valves to take with you. Again, I don't think is all that practical either. One thing is for certain, if you intend to get into tech stuff, you can't allow money dictate safety or quality gear.

Good luck.

Mike

 

[metridium]

Originally posted by Uncle Pug

Like Roak says the bands space the center of the cylinders.. right bands for each tank and you can use the same manifold.

That's the real question, I guess. We know what Highland Mills says about their own bands, but what about Dive-Rite 1033 bands? From D-R's website "Bands, for Tanks up to 7.50-inch Diameter (set of 2)" Is it the board's opinion that these are worthless?

Originally posted by Uncle Pug
No... not at all suggesting that you should ditch your BP/Wing Long hose.... just suggesting that double steels might be overkill afor a rec. travel dive.

Sorry, there should have been a winking smiley in what I wrote. Oops.

Originally posted by Uncle Pug
As for the regulator failure...
It was on the surface... but if it had failed on a dive would you not have had plenty of time to do a safe ascent??? If you were diving singles and took along and extra regulator you could just swap it out at the surface and continue diving.... but if that extra regulator is part of a twinset then what do you do other than sit out the days diving?

Safe ascent? Probably. But what if it had happened in a swim-through, or if I'd incurred a (slight) deco obligation?

If a reg on a set of doubles goes out when I'm rec diving, I could always use the reserve reg I've borrowed for the trip.

Originally posted by Uncle Pug
I am not convinced that twin tank diving is better for the standard recreational reef dive. And it definitely complicates logistics!

Definitely agree with the last, and possibly the first as well (it's certainly applicable for the majority of rec divers). To be honest, my first instinct was to go with a single tank with an H-valve, for simplicity's sake, but then I started thinking about tank valve o-rings and burst disks, and how this would be good training and acclimatization for using doubles in technical training later on.....

 

[Lost Yooper]

My burst disks ain't goin' anywhere . One thing about the H-valve is that it would get you thoroughly familiar with the hose routing of doubles which is nice too.

Mike

 

[metridium]

Originally posted by Lost Yooper
I'm not sure that assembling doubles on a rec diving vacation is all that practical though.

I'm beginning to have doubts myself. I'd been told that it takes only about 20 minutes to install the manifold and bands, so it seemed like a good idea.

Originally posted by Lost Yooper
If you're concerned about first stage failure (which I wouldn't beon a warm rec dive), then maybe get a couple H-valves to take with you. Again, I don't think is all that practical either. One thing is for certain, if you intend to get into tech stuff, you can't allow money dictate safety or quality gear.

Well, I have had one first stage failure on a series of dives cold enough for a drysuit already. I guess the H-valves are the way to go, then. Still, the idea of that reserve gas for the occasional solo dive is very appealing.....

As for the quality gear, I hear ya. My concern on whether the D-R bands would work on both 72s and AL80s wasn't cost, but rather practicality and simplicity.

 

[roakey]

Originally posted by metridium
...but what about Dive-Rite 1033 bands? From D-R's website "Bands, for Tanks up to 7.50-inch Diameter (set of 2)" Is it the board's opinion that these are worthless?

Q: What are bands used for?
A: They're to render safe a 3000psi bomb that's located mere inches away from the base of your skull.

For this reason alone I would avoid any one-size-fits-most bands, not to mention the HM’s have bolts instead of threaded rod and all my HM bands have fit *prefectly*. So perfectly that the crossover spins freely at least a half a revolution after assembly.

If I thought the Dive Rite’s were a good alternative, I would have looked into them. I don’t and I didn’t. So I can’t speak to them.

Roak

Ps. I dove recreationally with doubles for several months before I headed to GUE for my cave course. I'm glad I did, though it would not have been a problem if I hadn't. The first time you stand up with twin 104s on your back is a real eye opener. I stand 6'1", before I got my doubles I was 6'6"

 

[Lost Yooper]

I'm a bit slower at assembling doubles -- I take my time. It takes me about 45mins from the time I screw in the first valve until I put the BP on. Make sure you don't cross-thread the isolator part -- hasn't happened to me, but it can happen. I also use the HM bands .

Mike

PS. I love my double 95's for the boat diving we do.

 

[metridium]

Originally posted by roakey

Q: What are bands used for?
A: They're to render safe a 3000psi bomb that's located mere inches away from the base of your skull.

For this reason alone I would avoid any one-size-fits-most bands, not to mention the HM’s have bolts instead of threaded rod and all my HM bands have fit *prefectly*. So perfectly that the crossover spins freely at least a half a revolution after assembly.

Okay, Roak, I'm convinced. I'll get specific bands for specific tank sizes.


I'll probably also go the H-valve route. Are there any H-valves that are better than the rest?

Also, in case I don't, is there any reason not to use double 72s based on buoyancy characteristics? I'm a bit confused, because some of the shops I spoke with said they carry LP 72s, but at 3000PSI, they sound HP to me. Could they mean 78s or another size?

 

[metridium]

Originally posted by Lost Yooper
I love my double 95's for the boat diving we do.

Strictly technical?