Why don't wings have shoulder dump valves?

[boulderjohn]

Rather than start a new thread, I figured I'd ask here because it seems related to a BP&W discussion and the initial question has been answered. So I hope this isn't considered a thread highjack.

I dive a BP&W 95% of the time with a single tank and this issue did not occur when I dove doubles. I keep my backup reg on a necklace around my neck. Whenever I place the tank a bit lower so as to reduce the amount the valve of the tank is directly behind my head, the hose for my backup seems to get caught/hung up on my wing. When I have the backup reg in my mouth, this prevents me from being able to turn my head left much unless I reach back with my right hand and slide the hose up a bit.

Is this just the reality of a BP&W rig and diving with the tank valve directly behind my head is the best/only option? Having the valve that high is uncomfortable and seems unnecessary when using a single tank. Might it have something to do with using an STA? For example, if I did not use an STA and the tank sat closer to my BP&W perhaps the hose would not get caught up?

Obviously, I could put in some pool time and experiment with configurations, but getting a head start on ideas would be nice before doing that. Thx.

We talked about this before. I was baffled then, and I am baffled now.

I, too, switch regularly between doubles and singles. I, too, use a STA to make the switch easier. I have enough regulators to have a single tank setup and doubles setup, so I don't have to switch hoses, but my alternate hose for my single tank setup is the same length as the one for my doubles. Since it does not have as far to go, it is actually a little too long in the single tank setup. I have never had the problem you describe.

From what you describe here, it almost sounds like your alternate hose is too long.

 

[rx7diver]

... Whenever I place the tank a bit lower so as to reduce the amount the valve of the tank is directly behind my head, the hose for my backup seems to get caught/hung up on my wing. When I have the backup reg in my mouth, this prevents me from being able to turn my head left much unless I reach back with my right hand and slide the hose up a bit.

Is this just the reality of a BP&W rig and diving with the tank valve directly behind my head is the best/only option? ...

@Dan G,

What 1st stage are you diving?

Whether I dive a single Scubapro Mk 10 first stage (turret down) or a single Poseidon Odin first stage, I "cant" or "angle" the first stage slightly. This effectively angles upward (a bit) the IP regulator hose leaving the right side of the first stage (and angles downward a bit the HP hose leaving the left side of the first stage). Using this approach, my IP hose doesn't get hung up on my wings or my Scubapro Stab Jacket.

Hope this helps.

rx7diver

 

[Dan G]

We talked about this before. I was baffled then, and I am baffled now.

I, too, switch regularly between doubles and singles. I, too, use a STA to make the switch easier. I have enough regulators to have a single tank setup and doubles setup, so I don't have to switch hoses, but my alternate hose for my single tank setup is the same length as the one for my doubles. Since it does not have as far to go, it is actually a little too long in the single tank setup. I have never had the problem you describe.

From what you describe here, it almost sounds like your alternate hose is too long.

I'm baffled, too. The hose being too long makes sense. My alternate hose is 22" long. DGX has 18" hoses I could try.

 

[Wibble]

Rather than start a new thread, I figured I'd ask here because it seems related to a BP&W discussion and the initial question has been answered. So I hope this isn't considered a thread highjack.

I dive a BP&W 95% of the time with a single tank and this issue did not occur when I dove doubles. I keep my backup reg on a necklace around my neck. Whenever I place the tank a bit lower so as to reduce the amount the valve of the tank is directly behind my head, the hose for my backup seems to get caught/hung up on my wing. When I have the backup reg in my mouth, this prevents me from being able to turn my head left much unless I reach back with my right hand and slide the hose up a bit.

Is this just the reality of a BP&W rig and diving with the tank valve directly behind my head is the best/only option? Having the valve that high is uncomfortable and seems unnecessary when using a single tank. Might it have something to do with using an STA? For example, if I did not use an STA and the tank sat closer to my BP&W perhaps the hose would not get caught up?

Obviously, I could put in some pool time and experiment with configurations, but getting a head start on ideas would be nice before doing that. Thx.

With doubles the short hose is wrapped around the back of your neck pulling the hose closer in so the longhose isn't interfered with.

On a single tank the short hose is higher and lifts the longhose up. It also tends to stick out sideways from the regulator as opposed to downwards with a doubles regulator set. Basically the two hoses interfere with each other. It’s worse if using a 1.5m/5ft longhose which routes under your RH armpit at a flat angle and may catch under the necklace.

A single tank short hose is, in my experience, shorter than a doubles short hose.

Subtleties. Still a lot easier and a lot better than an octopus rig.

 

[Nemrod]

Why don't wings have shoulder dump valves?​

Because the Hog(arthian) concept of minimalism that largely drives tech design eschews complexity in favor of simplicity. If it is not needed then it gets left out. Thus simple one piece harnesses and wings with a butt dump and a short inflator hose without any sort of pull dump to rip the elbow from the bag at the worst possible moment.

 

[Eric Sedletzky]

Why no shoulder dump?
One less orifice that can fail, leak, crack, break.
Use the butt dump. Some people never even use the left inflator to dump, only to inflate. In fact they have the end secured down to the shoulder strap so it won’t hang down and bang into things.

 

[Nemrod]

I'm baffled, too. The hose being too long makes sense. My alternate hose is 22" long. DGX has 18" hoses I could try.

Generally a 22 or 24 inches inch hose is preferred for single tank Hog rigs for the secondary reg. You can try an 18 but that might be awfully short and restrict head movement. I suspect your problem is that the non optimal bent doubles plate combined with an STA forces your cylinder up too high behind your head and along with it the wing which then catches on the secondary hose loop. Maybe someday something like a Freedom Plate or a VDH plate will once again be available to single tank divers rather than attempting to use a raised center channel doubles plate which is not optimal. IMO, the center of the valve outlet should be located at approximately the cervical vertebrae which if I recall is C7. Not up behind your head or at C1. This high position is forced by the STA because the upper cam band position drops off the shoulder of the tank if attempted to lower further. I do not have any of these issues with my Freedom Plate or VDH plate or Oxy Ultralite plates.

James

 

[Couv]

Maybe someday something like a Freedom Plate or a VDH plate will once again be available to single tank divers

That day is today:
Freedom plate order thread:
https://scubaboard.com/community/threads/official-freedom-plate-list-please-respond-here.570671/

VDH style plate order thread:

Gauging Interest in DH backplates...

All I have ever used was the plastic and metal shaped plates for singles and doubles. Figured I would make a plate to facilitate diving DH with modern accouterments. Of course I am not the first guy to do this...from what I know, it started with Seacraft... Then VDH, and now not to be had...

scubaboard.com

I wholeheartedly agree with @Nemrod that modifying a doubles plate for single tank diving is suboptimal. Get a plate designed for single tank diving-use a wing that does not have the corrugated hose in the middle. Customize the length of the corrugated hose and inflator hose after mounting the wing/plate/regulator on a tank.

 

[NW Dive Dawg]

I didn't take the time to read all of this thread......but my guess as to the answer of the OP's actual question is that there are a lot of folks who dive wings who feel that the only proper way to dive is a perfectly horizontal position while pressing the back of their head as far back as possible onto their shoulder blades.

I get that and I prefer to be horizontal for "most" of my dive, but I'm sometimes in a head up vertical position where a shoulder dump is preferable....at least for me..

Examples are:

On long surface swims to my drop zone I like to swim on my back with an inflated BC. (and for the record, I am of the opinion that a wing is in fact a BC / Buoyancy Compensator). Once at the drop zone I like to relax a bit, take off my cheap sunglasses and stow in a pocket, spit and rinse my mask, set my compass for the exit spot and then use my shoulder dump to begin my descent... Once I'm a few feet underwater then I go horizontal..

Also, I like to stay horizontal at my safety stops if they are on a line or in the blue....Then when I ascend, I go vertical heads up and kinda do a 360 while looking in all directions as I surface... Shoulder dump works best for this...

Lastly there are some dives that are just naturally set up for a heads up vertical position. On the Great White Wall in FIJI I remember a dive where we descended to about 110 - 120 and then ascended up through a vertical "tunnel" that came out at about 30-40 ft. Horizontal would not have been practical on that ascent.

 

[Dan G]

Generally a 22 or 24 inches inch hose is preferred for single tank Hog rigs for the secondary reg. You can try an 18 but that might be awfully short and restrict head movement. I suspect your problem is that the non optimal bent doubles plate combined with an STA forces your cylinder up too high behind your head and along with it the wing which then catches on the secondary hose loop. Maybe someday something like a Freedom Plate or a VDH plate will once again be available to single tank divers rather than attempting to use a raised center channel doubles plate which is not optimal. IMO, the center of the valve outlet should be located at approximately the cervical vertebrae which if I recall is C7. Not up behind your head or at C1. This high position is forced by the STA because the upper cam band position drops off the shoulder of the tank if attempted to lower further. I do not have any of these issues with my Freedom Plate or VDH plate or Oxy Ultralite plates.

James

That day is today:
Freedom plate order thread:
https://scubaboard.com/community/threads/official-freedom-plate-list-please-respond-here.570671/

VDH style plate order thread:

Gauging Interest in DH backplates...

All I have ever used was the plastic and metal shaped plates for singles and doubles. Figured I would make a plate to facilitate diving DH with modern accouterments. Of course I am not the first guy to do this...from what I know, it started with Seacraft... Then VDH, and now not to be had...

scubaboard.com

I wholeheartedly agree with @Nemrod that modifying a doubles plate for single tank diving is suboptimal. Get a plate designed for single tank diving-use a wing that does not have the corrugated hose in the middle. Customize the length of the corrugated hose and inflator hose after mounting the wing/plate/regulator on a tank.

I use a HOG backplate which seems to be designed to handle a single tank well, given the fact that it has the indentation you described and the hose on the side.

I think I should go back to not using the STA since I do not switch between doubles and a single tank often at all. My wing is a Dive Rite travel EXP which has large openings that allow for the cam bands. I went to the STA because I felt the tank was moving, but perhaps I did a poor job of putting the bands in place or maybe just needed to get used to the feel of a BP&W since this is my first.