Questions For Double Hose Regulator use

[Wetsuit 4 life]

I have five questions that I would like to know the answers to before i start using my double hose regulator, some of them probably are not very impotent or maybe not even an issue with this type of equipment, but if anyone can help it would be greatly appreciated.

1. Is there a depth limit for double hose regulators?
2. Can they free-flow and what is the solution?
3. Is Freeze up a possibility?
4. 02 limit, if i really wanted to could i use Nitox 30
5. And is buddy breathing possible and how?

Thanks for any input

 

[Nemrod]

I have five questions that I would like to know the answers to before i start using my double hose regulator, some of them probably are not very impotent or maybe not even an issue with this type of equipment, but if anyone can help it would be greatly appreciated.

1. Is there a depth limit for double hose regulators?
2. Can they free-flow and what is the solution?
3. Is Freeze up a possibility?
4. 02 limit, if i really wanted to could i use Nitox 30
5. And is buddy breathing possible and how?

Thanks for any input

Wow, were to begin?

1. The same limits as would apply to any open circuit scuba.
2. Any regulator can free flow, if a double hose free flows put it in your mouth were it belongs
3. Double hose regulators are by design very resistant to freeze up.
4. You can prepare a double hose for use with any mixture, I use Nitrox often.
5. Of course buddy breathing is possible.

You should purchase an old time book like "The New Science of Skin and Scuba Diving" in a copyright of 1968 or earlier. These older texts show all of the aspects of double hose diving but some misinformation also. By the late 50s most all double hose regs were equipped with cage valves, one way valves, in the mouthpiece which essentially eliminated breathing hose flooding and the need to "milk" a hose or roll to clear maneuvers etc. However, it is good to know how to perform them. Buddy breathing is done by sharing the mouthpiece, the hoses are flexible enough that you roll the mouthpiece to the OOA diver. You do this facing one another and ascending.

Visit Vintage Double Hose and Vintage Scuba Supply - Antique Diving Gear Two Hose Regulators . Both have a forum as well with more in depth knowledge than this forum.



N

 

[Nemrod]

Just to be clear, diving with a double hose does require some training. It is not hard but it can be very different from a single hose. Some of us learned originally on them as did I. Others have been buddy mentored or learned on their own but in any case, given your questions, I would spend some time in a pool. But that is me.

N

 

[herman]

Nemrod covered it but thought I would put in a couple of more comments.
1. Is there a depth limit for double hose regulators?
A dive buddy of mine - 60's Navy diver- tells me he often dove DA Aquamasters to 150+ in the Navy. In some of the old text I have read of dives in excess of 200ft, not something I would care to do but then again I would not do it on moden gear either- no desire to. I personally have had my Phoenix (converted DAAM) down to 100 ft.

2. Can they free-flow and what is the solution?
I have had mine freeflow (due to me trying to tweek the last bit of performance out of it) and frankly it's less of a deal with a double hose than a modern reg, all the bubbles go out the back instead of in your face. Just keep the reg in your mouth and head for the surface or shift to a postion that is less prone to freeflow.

3. Is Freeze up a possibility?
Not for me...I like warm water.

4. 02 limit, if i really wanted to could i use Nitox 30.
Mine has seen a lot of 32% and I see no reason not to push that to 36%. I suspect Nitrox might be hard on old diaphrams and other rubber parts but if you are diving it to the extent you need Nitrox then it should have all new silicone parts in it anyway.

5. And is buddy breathing possible and how?
What N said.

 

[SwimJim]

Cousteau dove the Brittanic at 400 fow with a double hose. The first divers on the Andrea Doria in '56 dove double hoses. I have been down 130 with mine. Like Nem said the technique is a bit different then a single hose and a little study and pool time would be of great benefit.
If you get a two stage reg with a hooka port like a DA Aquamaster or a Royal you can rig an octo off of it. Although buddy breathing can be accomplished with a double hose, both parties have to know how to do it. An octo or a pony is a better option in the real world, IMHO.
Double hosers make great ice diving regs as they are not prone to freezing up. By design they are environmentally sealed. I dove December 7th with my PRAM and had no problems with 32 degree water and a 15 degree air temp. Stiff west winds too. The brass monkeys were covering up that day! LOL.
Currently, I've been sticking to 21% nitrox but I know others use it with thier regs.

Jim

 

[herman]

By the way in case your wonding, a PRAM (Phoenix Royal Aquamaster) is a modified DA or Royal AM that has been modified with a Phoenix nozzle upgrade.

Jim after seeing your picture on that dive.....your nuts old buddy
How much extra they charging you for 21% nitrox ?

 

[Nemrod]

This is a bridge at Table Rock Lake, note depth:

This is my self portrait on the deck of the USS Oriskany at 137 feet kneeling on the deck:

Several years ago a group of divers at one of our vintage dive rallys at Lake Wazee went to 200 feet. I accompanied to about 90 feet but was not outfitted with exposure gear appropriate for the dive--it was frigid down there. I have made numerous dives in the 150 foot range with my PRAM. Breaths at 150 feet pretty much like it does at 10 feet.

JFYI, most parts for the Aqua Master line of regulators are available still from the links I gave and many are improved silicone replacements. My PRAM has all Viton O rings, all silicone rubber parts, it was assembled with O2 compatible lubricants, it could I suppose be used at 100% O2.

N

 

[reefrat]

Hey Nemrod
What BCD or PB/wing are you using now with your PRAM?
RR

 

[Nemrod]

Hey Nemrod
What BCD or PB/wing are you using now with your PRAM?
RR

Usually a custom Freedom Plate and an Oxy Mach V 18 or 30. Several of us have similar rigs.

Or of course, nothing works too.

N

 

[reefrat]

Does the top of the Mach V wing press against the regulator body when the wing is inflated (assuming the tank is mounted low) and is this a problem or a non-issue?
Also, do you know if there is a mouthpiece unit available that wil fit the (P)RAM that is not one piece and would allow the fitting of a Seacure mouthpiece??
Cheers
RR