Deep dives with Argonaut Double hose (305ft)

[Luis H]

I did design the Kraken, the DSV, the HPR, the Phoenix, the Hurricane (can't even remember all the names) and a few other stuff for VDH. Bryan is a friend and I try to support him since he has been making the parts, but I am not part of VDH.

I do try to design the stuff with consideration for production, in particular low rate production. Including using the least number of parts, but production is all up to VDH.

 

[Luis H]

My apologies, I had it in my mind you were VDH's chief Design Engineer responsible for the Kraken and DSV initial development and final production?

I should add, I just retired from my primary engineering job a few months ago... I can now for the first time in my life claim that I have "No responsibilities"...

OK, that is not entirely true, but let me dream for a moment...

 

[tbone1004]

I should add, I just retired from my primary engineering job a few months ago... I can now for the first time in my life claim that I have "No responsibilities"...

OK, that is not entirely true, but let me dream for a moment...

yeah go tell Liza that you don't have responsibilities, let me know how that goes Miss my niece kitty already!

 

[rx7diver]

@Luis H,

This is neat!

Have you considered putting/keeping "regular-sized" (or larger) holes at the "bottom" of the can. I'm thinking what might happen with the tiny holes if someone should vomit into the mouthpiece when breathing your modified AK. Could the "chunks" eventually block the tiny holes?

Would this compromise the gains?

This also concerns me when breathing my 1st-gen PRAM (which still has a duckbill exhaust valve).

rx7diver

 

[Luis H]

NO...
If you feel like vomiting, go to your octopus. If you vomit into a DH you cannot breath out of it until you take it apart and clean all of it. You will aspirate...

Never mind... I don't want to think about this.

Sorry... I am an EMT and ski patrol, but there are certain things I don't want to deal with, while diving.

 

[Luis H]

The hole size are the same all around. What is the bottom when you are horizontal or swimming down?

 

[rx7diver]

What is the bottom when you are horizontal or swimming down?

Well, I am thinking the diver would be angled 10 degrees (or so) head up. Like you, I prefer to not dive "board flat." (Too hard on this old diver.) I will dive flat if I am cruising from point A to B. Otherwise, if I am lingering, I likely am NOT board flat.

rx7diver

 

[mdwalter]

Back to our regularly schedule programing…
And don't worry... I will dive with you even you follow "unsafe" practices... just kidding...

Here is a sneak preview of my exhaust silencer 3D printed exhaust can.

This is the regulator I normally use, but I changed it to DIN fitting, removed the octopus, and added the cross-over LP hose.

The exhaust silencer is made from 1000 tiny holes (OK, only 999 to be exact).

The sum of the exhaust gas flow area is several times that of the cross-sectional area in the exhaust hose or any of the exhaust gas path. So, I have done lots of calculations and lots of testing (properly instrumented and otherwise) and the flow impedance from this modification is barely measurable (or actually not at all).

The exhaust is broken down into tiny bubbles, which quiets it down to a much lower sound than the intake noise. I don’t have the instrumentation for acoustic testing, so all I can do is comparison testing.

I will have a lot more info to follow, including some inside pictures. I made some really nice changes to the inside valve area also.

View attachment 740932

The regulator on the right is my primary regulator. These are my two working prototypes.

More to follow. Note, the back cans are the original injection molded.


View attachment 740933

Now that's super cool! It even looks better than the original can. Maybe if you go to production some day you could offer it in basic black, as well, to keep with the original AK color scheme. Would this type of silencer work on a JetAir, as well?

 

[Luis H]

Now that's super cool! It even looks better than the original can. Maybe if you go to production some day you could offer it in basic black, as well, to keep with the original AK color scheme. Would this type of silencer work on a JetAir, as well?

I am not exactly sure what you are asking about a JetAir.

If you are asking, if the concept will work, absolutely. This is just the exhaust noise I am reducing. The inhalation is not affected.

If you are asking, if the same can will fit, I think it will, but I am not positive. All these regulators use the same diaphragm diameter and I know that my bolt pattern is the same as in the Voit plastic cans. I think the JetAir also uses the same bolt pattern, but I never checked.

But I have no idea if the cans will be available. Bryan (from VDH) only produced the cans for the Argonaut. He never intended on just selling cans.


Like I mentioned above, I don’t produce anything. I just design, fabricate prototypes, and test them.

I don’t know the future of this concept and I have not talked to Bryan (@Bryan@Vintage Double Hose).

Producing this in quantities could be fairly difficult, but there are some possibilities. We will see.


Note: In post #18 I made a comment about how difficult it was to work with a black 3D printed can.

 

[Luis H]

I have been wanting to try my Argonaut in this configuration, for deep diving. The use of a single cylinder on the back with a side mount cylinder, with the LP hose cross-over gave me advantages of independent doubles, or the flexibility of always breathing from the DH, without switching regulators second stages.

The only downside (IMHO), is that there is extra real-estate on my back for a second cylinder that is not being used, but it is hard to reach those valves, so I am OK with that. And not having to carry doubles out of the water is a side benefit.

I don’t have many opportunities of doing these types of dives, but I will always have the option. It doesn’t require any special manifolds or special equipment.





The concept of an exhaust silencer is not new. The implementation is what becomes is a bit more of an issue, or a challenge.

I do know of at least one European Navy using a semi-closed rebreather with an exhaust silencer. The US Navy uses closed circuit rebreathers.

In a semi-closed rebreather, it is a bit easier because you are just dealing with about 1/3 of the exhaust on every breath... roughly...

I have copies of about 10 different patents for a number of exhaust silencers, from big attachments to the exhaust of a regulator, to even a hood where the exhaust is channeled into many little bubbles. Most of the patents are very old and none of them resemble what I am doing, but similar principle.