Info Are Pony Bottles Dangerous?

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Something has been bothering me in this thread and I just can't keep it in anymore. All this discussion of pony bottles, double tanks with separate valves and first stage systems, triple second stages, minimum gas this and that, quadruple redundant dinkle whoppers, minimum pressures, etc. etc. etc. All in the name of making a dive as safe as possible while still being exciting.

Ok, so what happened to the built in reserve, the "J valve"? That was a built in reserve that was factory set at 500 PSI and could be adjusted up to 750 PSI. I still remember my training on it the early 70's. It was intense. The whole class walked around for six months waving our left hands behind our backs looking for the handle like we were waving away stinkers. lol.
 
Something has been bothering me in this thread and I just can't keep it in anymore. All this discussion of pony bottles, double tanks with separate valves and first stage systems, triple second stages, minimum gas this and that, quadruple redundant dinkle whoppers, minimum pressures, etc. etc. etc. All in the name of making a dive as safe as possible while still being exciting.

Ok, so what happened to the built in reserve, the "J valve"? That was a built in reserve that was factory set at 500 PSI and could be adjusted up to 750 PSI. I still remember my training on it the early 70's. It was intense. The whole class walked around for six months waving our left hands behind our backs looking for the handle like we were waving away stinkers. lol.
J Valves were originally a result of no SPG's. You still have that exact same reserve amount in your main tank at all times..... Just need to pay attention as to when you get that reserve point. If you have an AI computer, just set an alarm for 750 or 500 and you'll have the same benefit of the J valve without the need to find and pull the rod extension.

What a J valve cannot do is provide redundancy to mitigate a catastrophic failure of your primary system.

The J Valve also has the problem of a potential for the "lever" to be inadvertently or accidentally actuated.
 
Something has been bothering me in this thread and I just can't keep it in anymore. All this discussion of pony bottles, double tanks with separate valves and first stage systems, triple second stages, minimum gas this and that, quadruple redundant dinkle whoppers, minimum pressures, etc. etc. etc. All in the name of making a dive as safe as possible while still being exciting.

Ok, so what happened to the built in reserve, the "J valve"? That was a built in reserve that was factory set at 500 PSI and could be adjusted up to 750 PSI. I still remember my training on it the early 70's. It was intense. The whole class walked around for six months waving our left hands behind our backs looking for the handle like we were waving away stinkers. lol.
What was your typical dive profile back in the day?

Does that differ from the typical dive profile nowadays?

Consider gasses, tank volumes, depth, bottom time, decompression profile, etc. What about bend statistics and numbers of dives? Impact of technology now and then.
 
Something has been bothering me in this thread and I just can't keep it in anymore. All this discussion of pony bottles, double tanks with separate valves and first stage systems, triple second stages, minimum gas this and that, quadruple redundant dinkle whoppers, minimum pressures, etc. etc. etc. All in the name of making a dive as safe as possible while still being exciting.

Ok, so what happened to the built in reserve, the "J valve"? That was a built in reserve that was factory set at 500 PSI and could be adjusted up to 750 PSI. I still remember my training on it the early 70's. It was intense. The whole class walked around for six months waving our left hands behind our backs looking for the handle like we were waving away stinkers. lol.
I still have 2 1970s AL80s with J valves. They're dedicated lake tanks that get used sporadically and only if I don't have a partial steel HP tank to use for the job. They just don't work as well as HP steels in cold drysuit diving.

20220607_165556.jpg
20210814_144627.jpg
20210814_145520.jpg
 
The J Valve didn't originate because there were no SPG's but they did help with that problem. No, the J Valve can not help with all problems like a catastrophic failure of the primary system. Nor can it help when a crazy little psycho fish keeps biting your earlobe. It was never designed to do those things. It's just another safety device.

Regarding the problem of turning it on accidentally: That happens sometimes. The ones who get "caught by it" are the ones who didn't check it regularly. It comes down to training and I that's where the failure was. A lack of proper training resulted in divers forgetting to check the valve. That resulted in divers taking that last breath and not getting any more. Most of those that survived blamed the J Valve. "The stupid thing turned itself on and I almost died. I hate that thing". It's an easy thing to do. Check the SPG and then touch the lever to make sure it's up. Feel check yours and visually check your partners. It's just another safety device.

I have J Valves on my tanks because I like them. I hardly ever actually click my Reserve to On but it's nice to know it's there. Regarding the problem of finding the lever in the cold dark depths: Really? That's a silly reason. Do you have any trouble finding your SPG? How about your line cutter?

I get ragged on for using a J Valve. That's when they're not ragging on me about my Big Friggin' Knife strapped to my leg or my Horse Collar BC or my lack of a computer or my snorkel stuck thru my knife straps or my other vintage gear. That's ok. I'm vintage too. (I have a Great Grandson fer cryin' out loud) I laugh at them when they're trying to get their dang blasted computer to work right or they're having to use canned air on the surface because they don't have a snorkel but my best laughter comes from watching them trying to stay upright and float on the surface using one of those face planting automatic drowners that they call BCD's while I calmly float by grinning at them over my Horse Collar BC. If that's technological progress, I'll have to pass on it.
 
... Ok, so what happened to the built in reserve, the "J valve"? That was a built in reserve that was factory set at 500 PSI and could be adjusted up to 750 PSI. ...
I love the idea of using a J-valve. I prefer using a J-valve when I am diving my DH reg for solo recreational dives between shallow and moderate depths.

rx7diver
 
In the days of yore, the steam engine did not come into existence due to the absence of horse-drawn carriages, but it did play a role in addressing that concern. Alas, the steam engine cannot attend to all dilemmas, such as a catastrophic failure of the primary system or thwarting an erratic piscine rascal nibbling at one's earlobe. It was never crafted for such exploits. It stands as naught but another bastion in the realm of safety.

Concerning the issue of inadvertent activation: Verily, it occurs at times. Those ensnared by its unexpected embrace are oft the ones negligent in their routine checks. The crux lies in education, and there lies the shortfall. A dearth of proper training led drivers to overlook scrutinizing their levers, resulting in outings that concluded prematurely. Many cast aspersions upon the steam engine. "The confounded thing switched itself on, and I was nearly consigned to the side of the road. Detestable contraption!" 'Tis a simple ritual. View the window that lies on the side of the engine, and tenderly caress the lever to ensure its elevation. Verify your contraption has sufficient water and firewood. It stands as no more than an additional precaution.

I, for one, affix certain religious baubles to my contraption out of inclination. Rarely do I have to use the extra log I keep by my feet, but the solace of its presence is reassuring. Concerning the issue of locating the lever in the cold, stygian roads: Really? A frivolous rationale, if you ask me. Encounter any difficulty locating your steering lever?

I endure good-natured ribbing for my allegiance to the steam engine. That's when they're not poking fun at my Sturdy Blade strapped to my leg, my horse-drawn carriage, my absence of an abacus, or my derringer concealed in my top hat, among other antiquated accouterments. That's acceptable. I am a relic myself, with a great-grandson to vouch for it. I chuckle when they grapple with their infernal computing devices or resort to walking to the next farmhouse in search of assistance. However, my heartiest laughter arises from witnessing their struggles to remain upright on the road, employing those new-fangled petroleum-powered engines that travel at such great speeds. They crash and, meanwhile, I serenely float by, grinning from ear to ear though it may be difficult to see me due to the steam and smoke from the slightly green wood I have now to use. If that's the march of transportation progress, count me out.
 
https://www.shearwater.com/products/perdix-ai/

Back
Top Bottom