Questions For Double Hose Regulator use

[Nemrod]

Yes, the wing will press against the body and no, it is not an issue, to begin with, it is rare to fully inflate a wing and even if you do, the wings just forms around the can---not an issue at all in any way. Let em add however that what I say is true of wings like the Oxy design that has an off center corrugated hose elbow. Those that have the weird center elbow will probably be a problem. Why fool with those anyways when the Oxy is the bomb. Just in general, a double wing should have a center elbow, a singles wing should be offset.

Also, this thing about shoving the tank down so low, everyone says it, I don't agree. A wing places you in a very horizontal position, even slightly head down, there is no point in shoving the tank down so low if you are diving a wing/BP with your double hose, all it does it screw up trim to no other advantage.

No, I don't know of a mouthpiece that will allow a Sea Cure mouthpiece, I made one once from PVC as an experiment and decided it had no advantage to warrant pursuing.

Since most double hose regulator hoses are slightly buoyant, they don't pry on your teeth and jaw like a single hose regulator does. I have teeth implants thanks to a drunk driver, all single hose regs hurt my teeth, double hose do not because the mouthpiece is weightless.

IMO, the curved style USD mouthpiece is the most comfortable but alas it is the only one not yet reproduced in wonderful silicone, nonetheless, it is my favorite for comfort.

N

 

[reefrat]

Thanks again- all questions answered fully!!!
I am embarrassed to say that I bought a reconditioned RAM over a year ago and still haven't dived it!! In fact it's stuck in Australia right now with baggage that I couldn't bring with me last time.
But I hope soon to have it freighted over and upgraded to a PRAM to see if I can get closer to those flighty little critters with my macro lens.
As an aside, my wife and I bought a place on the beach late last year in Grand Turk and 4 weeks after buying (and renovating) it Hurricane Ike totally wiped it out!
We are currently rebuilding the place and in due course it will be our own little dive paradise complete with a bar to watch the sunset and 5 world class wall dives within 800 metres of the front door, can't wait to spend a lot more time there!
Cheers
RR

 

[herman]

Nemrod, have you tried the Voit reproduction that Bryan did? I got one and it's a lot like the curved USD one and a lot more comfortable than the silicone straight ones.

 

[Luis H]

I am aware of at least two DH mouthpieces were you can change the mouthpiece bite, but they are both very hard to find.

One is the vintage Hope-Page mouthpiece which happens to be one of the very early (if not the first) mouthpieces that included non-return valves. It is a very well design mouthpiece and has fairly low breathing resistance. It is also fairly low profile. It does require hoses with 1 inch opening in both sides, which are available, but not as common.

The Hope-Page mouthpiece occasionally show up on eBay (or attached to some regulator), but it is not very common and it normally sales for a fairly high price.


The other mouthpiece would be one from the modern Mistral. The Mistral as a whole was generally a failure, but one of the items that were carefully design was the mouthpiece. The mouthpiece takes some features from a re-breather mouthpiece. It doesnÃÕ have a DSV closing valve, but it has the well designed non-return valves of a re-breather.

The low breathing resistance of the new Mistral mouthpiece is excellent, but the compromise is that it is a relatively large mouthpiece. I personally own and have done a number of dives with this mouthpiece and donÃÕ like it size. It actually block downward vision (if I want to look down at my rig, etc.) and the buoyancy in conjunction with how far it sticks out created a torque on my mouth and it tends to move around. To use this mouthpiece I would recommend adding hose weight to make the hose mouthpiece combination neutrally buoyant.

The other problem with this mouthpiece is that it is not available by itself and it would be a waist to pay for a Mistral just for the mouthpiece. The Mistral is out of production anyway.


This leaves us with a vintage curve mouthpiece or one of the reproduction silicone mouthpieces. My favorite is by far the curve mouthpiece and there are plenty of them around in good condition. I like that it is very low profile and mouthpiece opening is high, putting the curved section down low and almost against your chin. The mouthpiece bite may not be the greatest, but it doesnÃÕ have to be. There balance and low profile of the unit creates very minimal loads on your mouth. You donÃÕ really have to bight on the mouthpiece; there should never be any jaw fatigue.

IMO the next best mouthpiece is the silicone reproduction hour glass Voit mouthpiece. Some divers actually like it better than the curve mouthpiece. Both of these mouthpieces are great and it makes sense that individual personal preference would exist between one and the other. They both share the low profile feature.

 

[Luis H]

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

You already got some good answers above, but I will try to add some to it.

1) I recently finished some tech diving classes using double hose regulators for my primary regulator. I personally prefer the simplicity (and therefore reliability) of a double hose regulator.
http://www.scubaboard.com/forums/vi...atest-technical-diving-regulator-phoenix.html

In the past I have used an Aqua Master down to 200 ft. A Phoenix Royal Aqua Master is now my regulator of choice for any deep or difficult dive.

2) Any regulator can free flow during a malfunction and a double hose will free flow by design if you remove the mouthpiece from your mouth and raise it (in the water) above the level of the diaphragm. This feature can be used to clear the mouthpiece since there is no purge button.

3) Most double hose have both the first and second stage environmentally sealed. It is possible to freeze flow a double hose. It is extremely rare, it did happen to me once ice diving, but I am not aware of it happening to anyone else. It took two concurrent malfunctions and some poor technique to cause the freeze flow (I was kind of pushing the limit and my luck).

The Royal Aqua Master was the regulator of choice in Antarctica until 1993 (about 20 years after they were last produced), due to its cold water performance.

4) I regularly use Nitrox with my DH. Up to 40% does not require O2 cleaning, but cleaning a DH for pure O2 would be easier than for a modern regulator due to its simplicity. A double hose would not lend itself for a stage or deco bottle; therefore IMO there is no point in cleaning it for high O2.

The rubber pieces (large diaphragm, hoses, duckbill, etc.) on a double hose are not affected by any high O2 since they are only exposed to ambient pressure (the same as your mask, BC, etc.).

5) Yes buddy breathing is very possible, but it does require practice and familiarization by both individuals involved. As mention by swimjim, it is a lot more practical to have an octopus, especially if you are diving with a mix crowd. To buddy breath with a double hose you have to be closer together and have to learn how to always clear the mouthpiece without the aid of a purge button. You can raise the mouthpiece, but many other divers may not know this.

 

[Nemrod]

Nemrod, have you tried the Voit reproduction that Bryan did? I got one and it's a lot like the curved USD one and a lot more comfortable than the silicone straight ones.

Yes, I have one and like all the stuff from vdh, it is an amazing piece that makes my Voit look right, it is more comfortable than the straight type for sure. However, I still much prefer the curved mouthpiece and besides, the Voit mouthpiece does not look right with an Aqua Master.

N

 

[SwimJim]

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 ?

That's okay Herman, being normal is way to boring. My local guy charges me a whole United States dollar for air fills. I haven't the slightest idea what he charges on real voodoo gas. I suppose I should learn up on that stuff as it would shorten my deco times when I go deep.

Jim

 

[John C. Ratliff]

Yes, I have one and like all the stuff from vdh, it is an amazing piece that makes my Voit look right, it is more comfortable than the straight type for sure. However, I still much prefer the curved mouthpiece and besides, the Voit mouthpiece does not look right with an Aqua Master.

N

Nemrod,

My LDS has a DA Aquamaster with a black, voit-like mouthpiece with a USD logo. Apparently, USD used it for a little while.

SeaRat

 

[Nemrod]

Nemrod,

My LDS has a DA Aquamaster with a black, voit-like mouthpiece with a USD logo. Apparently, USD used it for a little while.

SeaRat

Yeah, but it was not gray, lol.

N

 

[pescador775]

During 1971-72 I dove Caleta reef for black coral. Average depth was 260 feet. Regulator was Aqua Master. One day, a German guy named Minninger let slip a tank which tilted, fell over and bashed the front of my regulator. Even so, I was able to do the dive without problems.

O2 cleaning takes about 30 minutes unless you have an assembly/push tube then it takes half that time. Using a large wrench remove the high pressure block. Using a snap ring pliers remove the ring and spill out the hp seat, springs etc. If you have a RAM, remove the small O ring from the balance chamber (spring block). Dump everything into a cup of ENSOLV. Remove after a couple minutes. Grease up a viton O ring with Krytox or similar and place in balance chamber Reassemble everything.