Cylinder type and proper weighting (SPLIT FROM 'Pull Dumps - Lose them')

[johndiver999]

In a runaway inflation scenario, I have a hard time understanding how exerting yourself to the maximum extent possible, (kicking down super hard) and then inverting yourself and pulling the dump valve is a viable solution.

The problem I envision, is that it probably takes 2 hands to disconnect an inflator hose. If one hand is on a rear pull dump, you might be able to prevent an ascent, but you don't seem able to actually resolve the problem.

Exhaling completely, laying spread eagle on your back, dumping air from the inflator (via a pull dump or otherwise) - while you strive to disconnect the hose seems a much better, quicker and less strenuous solution. An Air 2 type connector is operable with one hand, but the "normal" ones aren't - in my experience.

Also, most stuck inflators I have seen are not blasting air 100% at full capacity. It is often a slight or moderate leak (that may not be so evident until you find yourself floating up in an unwelcome manner). So once you dump the excess air from the bC, are spread eagle to make a ton of drag - exhale (the fastest way to loose buoyancy), you have some time to disconnect the hose. That can all be done with near zero physical exertion. There is probably no need to shoot down as fast as possible, but rather to arrest the ascent ASAP, disconnect the hose and then you have some time to check air supply, depth, time and determine how you want to proceed.

 

[AdivingBel]

LOL...thanks for the advice. I do appreciate it , but I don't want twins and I only carry 4 lbs. of lead and no exposure protection other than a full lycra. I'm only diving in tropical waters. I do grab a pony for solo, though. Happy diving.

 

[boulderjohn]

the problem here is simple people are carrying to much weight and trying to compensate with a wing or bcd. get rid of aluminium cylinders and you won't have to carry lead to compensate for their bouyancy when empty. If you use a neoprene drysuit and trim properly you'll have no use for a bcd or wing. The scuba industry have everyone conned into buying to much gear and convinced them that they need it.

You have to carry enough lead to compensate for the greater buoyancy of a tank when it loses gas during a dive, and it does not matter whether a tank is made of aluminum or steel. If you and your gear, counting the tank and the weights you carry, are perfectly neutral at the beginning of the dive, and you lose 6 pounds of air during the dive, you will be six pounds positively buoyant at the end. You should therefore add 6 pounds of lead to compensate for that. If you are 6 pounds negative at the beginning of a dive and lose 6 pounds of air during the dive, you will be neutrally buoyant at the end--no matter the composition of the tank.

When diving with a 55mm suit, a steel back plate, and a steel LP 85 (Worthington) in salt water, I don't need any weight to do my dive. If I were to use an AL 80 instead, I would have to add several pounds of lead in order to achieve the exact same buoyancy. If I did that, my diving would be identical to my steel tank, except for the fact that i would have ditchable weight I could lose in an emergency.

 

[Celt]

You have to carry enough lead to compensate for the greater buoyancy of a tank when it loses gas during a dive, and it does not matter whether a tank is made of aluminum or steel. If you and your gear, counting the tank and the weights you carry, are perfectly neutral at the beginning of the dive, and you lose 6 pounds of air during the dive, you will be six pounds positively buoyant at the end. You should therefore add 6 pounds of lead to compensate for that. If you are 6 pounds negative at the beginning of a dive and lose 6 pounds of air during the dive, you will be neutrally buoyant at the end--no matter the composition of the tank.

When diving with a 55mm suit, a steel back plate, and a steel LP 85 (Worthington) in salt water, I don't need any weight to do my dive. If I were to use an AL 80 instead, I would have to add several pounds of lead in order to achieve the exact same buoyancy. If I did that, my diving would be identical to my steel tank, except for the fact that i would have ditchable weight I could lose in an emergency.

steel tanks have negative buoyancy, they have no buoyancy to compensate for. you cant breath lead why carry it.why would you have to ditch weight?

 

[Steelyeyes]

This is so true. When there is stress on the surface there is nothing like blowing up your BCD and getting your head way above the water.

I had one with a CO2 cartridge in it back in the day. The Navy still uses them since some of their guys dive, shoot, get shot at, and leave by water again.

 

[Diving Dubai]

I see that people like to add tasks to things.. KISS...

If the inflator is in your hand and sticks. The fastest and easiest way to get the air from going into the BC is by pulling on the hose to dump.. Then moving your other hand to remove the Low pressure hose.. No need to start finning down, find butt dump, find inflator AGAIN.. And then try and remove the LP hose with one hand..

Jim...

Without being controversial, disagree a little.

I had an inflator run away on an early dive - probably around the 40 mark and 20 since I'd re-started. So still inexperienced.

For me the most natural thing to do was to vent out of my butt dump whilst disconnecting the inflator with a couple of fingers.

In haste to do this of course it never crossed my mind that I could continue the dive by oral inflating I just finned up to the surface (from around 60' in a 7mm).

I'd probably do it differently now. Maybe I'd press the inflate and deflate button together (as is used when teaching OW students to simulate a runaway) maybe not. It'd be automatic whatever I did.

One thing would still remain the same in that I'd surface. I dive too often and am too damn lazy to be arsed with orally inflating during a dive. The only time I ever orally inflate is when deming the skill

 

[Soloist]

why would you have to ditch weight?

I understand the concept of ditching weight (AT THE SURFACE), but for the warm water diving we do carrying lead weight is not an option.

For vacation diving with aluminum tanks I dive a stainless Freedom backplate, lightweight Mikron regs, 13cf aluminum pony, 3.5mm wetsuit and a 5mm hooded vest. I am perfectly weighted, so I do not carry any lead. That being said, I do not have any “ditchable” weight at the surface. I’m okay with that.

In Florida I solo dive the same Freedom plate, regs, and exposure protection, but with a steel 120, 19cf aluminum pony and gear for hunting, so I sink like the proverbial stone. Occasionally I use an aluminum backplate, but I am still way heavy. Wish I wasn’t, but forget about it, I’m diving the steel 120’s!

 

[Dan]

steel tanks have negative buoyancy, they have no buoyancy to compensate for. you cant breath lead why carry it.why would you have to ditch weight?

Supposed you have the following problem during a dive, your BCD leaks (e.g., vent valve spring broke, a small dirt jammed on the vent valve seat, old plastic valve plate got brittle & cracked, etc.), starts to take in water & you become negatively buoyant in the blue water, then what would you do? Since you have no weights to ditch, you’d just keep finning on the surface to keep you a float until a boat rescue you?

 

[grf88]

Supposed you have the following problem during a dive, your BCD leaks, starts to take in water & you become negatively buoyant in the blue water, then what would you do? Since you have no weights to ditch, you’d just keep finning on the surface to keep you a float until a boat rescue you?

Go to your backup buoyancy device otherwise you will have to ditch your gear.

 

[Dan]

Go to your backup buoyancy device otherwise you will have to ditch your gear.

A lot easier to just ditch those weights.

A lot drowning accident victims were negatively buoyant. If I passed out during a dive. I want to be positively buoyant & float, not sink.