Why do Tech BC's have the butt dump on the inside, not the outside?

[Web Monkey]

beano, can you post a pic of the wing you're talking about?

Here you go. I think this is the one he has:

 

[beanojones]

If you ever got any wings from Dive Rite with dump valves facing away from the diver, I'd send them back. DR is usually very good about replacing manufacturing defects.

It's not a manufacturing defect, it's how the wings were made until the most recent revision AFAICT (the one with the backplate grommets labeled Travel 360). That one has the diver facing butt dumps:
SCUBA Diving Equipment for Technical, Wreck and Cave Diving: Dive Rite, Inc - Product Catalog - Travel 360 Wing

The old style:
Dive-Rite Travel Wings (30 Lbs. lift) # 2071 from LeisurePro.com

and the newer but not latest style:
Great deal on DIVERITE TRAVEL WINGS from Divers-Supply.com

Both have the rearward facing dumps.

(only talking about the Travel wings here. The other ones have always had front facing dumps AFAIK.)

 

[cool_hardware52]

If the OPV is properly located, near the outside profile of the wing, having it on the diver's side of the wing does not cause gas trapping. Raise your hips slightly, and pull the cord up and "around your back" and the wing can be fully vented.

This location allows the diver easier access to the valve. The diver does not have to reach "over" the wing to find the OPV.

It's not "fashion" that dictates the location of the OPV, it's the function.

Of course what the hell do I know, I've only designed, tested and refined 14+ different wing designs.........

Tobin

 

[redacted]

I think the issue here is that the Dive Rite travel wing is fairly small and heavy and does not tend to taco as much as other wings. I have an older style travel wing (30 lb lift) on one of my plates and the rear dump located on the outside of the wing tends to remain quite accessible, especially if it has the loop at the corner that the string (with ball) runs through. Another rig I have has an 18 lb Oxycheq wing with the ball on the inside. This wing does tend to taco a bit more and the string (ball removed) is more accessible with that location. (At least once I remember that the travel wing has the rear dump on the rite (sic) side and the Oxycheq has it on the left side.

It looks like DR make the rear dump location change from right-outside to left-inside when the went from 30 to 40 lb lift. I suspect that new design tends to taco a bit more which would make that change necessary.

 

[cmburch]

These pics may help. These are from SplitLip's post on SCUBAToys forum.

Taco Effect

Minimal to no tank wrap around.


It is easier to reach straight back rather than around the wing. And can be highest point depending on orientation.

 

[Doc Intrepid]

No, looking at the photos he supplied, the Dive Rite travel wing in fact appears to have a release on the right side of the diver, and facing the rear.

Considering that most bp/w divers use their left hand to dump gas from their wings, and need their right hand to work the scooter, etc., it seems Dive Rite deliberately designed the product to mess with people's SOPs. Who knows why?

Most likely and most productive answer would be to contact Dive Rite. But the photo clearly shows a funky design.

FWIW.

 

[redacted]

No, looking at the photos he supplied, the Dive Rite travel wing in fact appears to have a release on the right side of the diver, and facing the rear.

Those links were to the older style 30lb lift travel wing. This is the new travel wing, Travel 360, (SCUBA Diving Equipment for Technical, Wreck and Cave Diving: Dive Rite, Inc - Product Catalog - Travel 360 Wing) with current conventional valve placement and 40lb lift. I can't imagine why anyone would need a "travel" wing with 40lb lift. I suspect the older design goes back quite a ways, pre-dating the current norm for valve placement.

 

[ACR]

Personally I like to use my right hand, reach all the way around my back, wing and tank to pull the dump on the left. Maybe it's just me.

 

[beanojones]

No, looking at the photos he supplied, the Dive Rite travel wing in fact appears to have a release on the right side of the diver, and facing the rear.

Considering that most bp/w divers use their left hand to dump gas from their wings, and need their right hand to work the scooter, etc., it seems Dive Rite deliberately designed the product to mess with people's SOPs. Who knows why?

Most likely and most productive answer would be to contact Dive Rite. But the photo clearly shows a funky design.

FWIW.

Uunfortunately Dive Rite was less than helpful when contacted since they said the dumps have always been located facing the diver. (I have owned Travel wings for 11 years and they have always had rear right facing butt dumps, until the last revision. I have six of them now for use in a rental fleet that are all the same.)

I assume that the Travel Wings were designed, originally at least, to be used as rec wings with the transpac, following the standard butt dump placement (right side, rear facing). It is only in the latest version that they were even grommetted for use with a BP.

I am definitley going to use these as rec equipment, as the divers using them will be OW students or intro divers, or just regular old fun divers. So for me the SOP is the rec standard, not the Tech/DIR SOP.

 

[beanojones]

These pics may help. These are from SplitLip's post on SCUBAToys forum.
Taco Effect
.

I edited that first pic to circle the air trapping space that front mounting dump cause. A rear dump pulled to the rear can be pulled back to make it the highest point. IME the front mounted dump is limited by the length of the fabric, and can never dump that last bit.