Deep dives with Argonaut Double hose (305ft)

[Wibble]

you specifically called out wreck penetration and cave diving, do you actually dive in those environments? If you are, then you should be diving with 2x bailout cylinders, and most that are doing that with a "standard" backmount CCR are doing that with sidemounted bailout bottles with a "traditional" sidemount hose configuration and then all other bottles are left hand side only. Again, if you're in a BSAC dominated area then it may be different but no one else in the world is advocating that nonsense to my knowledge, similar to no one else advocating for secondary take except for BSAC.

Please find an example of any article written in the last 10 years advocating for left lean right rich because I would truly love to see it, same for any reputable instructor actually teaching it.

As to why wouldn't you split them? Dive with up to 2 "loaded" and any extras stick on a tail leash. You don't need all that stuff cluttering your body so when you don't need them put them in a bouquet between your legs. It is way easier than trying to fit that many on your body.

Also you clearly don't scooter as trying to scooter with low slung stages on both sides is really uncomfortable and incredibly inefficient.

Sidemounted bailout. Streamlined and under control. When inside a wreck they don't snag. When outside they don't catch on discarded fishing gear.

Use standard "handed" valves, a loop bungee which has tails so thick gloves work, a second lower D-ring on the harness, standard stage rigging kit canted 45 degrees inward, regulators are in to the body so out of the way, easy to access in the standard way. Works with ali7s (50cf?) and ali80s.

Does not get in the way of a scooter -- sidemounted stages don't dangle.

My playground... Wrecks along 30 miles of the south coast. There's thousands of others around the UK.

 

[Wibble]

As to why wouldn't you split them? Dive with up to 2 "loaded" and any extras stick on a tail leash. You don't need all that stuff cluttering your body so when you don't need them put them in a bouquet between your legs. It is way easier than trying to fit that many on your body.

Klang, clatter, bang as the dangly, floaty, uncontrolled stages clout the wreck when inside. Problems backing out of holes. Would have thought you cave divers would hate that in restrictions. Which is why sidemount was invented.

Also you clearly don't scooter as trying to scooter with low slung stages on both sides is really uncomfortable and incredibly inefficient.

Am embarrassed at the failure on my part to adjust the waist D-ring with a floaty stage. The other is behind my body, as it was sidemounted, it wasn't dangling as yours would. 60m/200ft in Ireland.

 

[tbone1004]

Klang, clatter, bang as the dangly, floaty, uncontrolled stages clout the wreck when inside. Problems backing out of holes. Would have thought you cave divers would hate that in restrictions. Which is why sidemount was invented.


Am embarrassed at the failure on my part to adjust the waist D-ring with a floaty stage. The other is behind my body, as it was sidemounted, it wasn't dangling as yours would. 60m/200ft in Ireland.

how do you know my stages dangle? They're very much streamlined, but that's still only 2 total bottles, not 4 and anytime you have more than 1 bottle per side they do clang when you move around.

 

[Wibble]

how do you know my stages dangle? They're very much streamlined, but that's still only 2 total bottles, not 4 and anytime you have more than 1 bottle per side they do clang when you move around.

If they're not bungeed back, they'd be dangling free to move around as they please.

As we both know, dangling stages suck your propulsion energy as they swing backwards when you kick forwards, then fall down and slow you, sucking your input energy. If using two stages left (or right) then they tend to hold each other in place and not swing around so much.

Dangling stages also tend to be bottom up when light gasses are used. Putting a 'heavier' stage on top of a lighter one (e.g. rich left, lean right) will keep the lighter one down BUT then you need to NoTox validate your regulator to the cylinder and gas before using it in an emergency (e.g. caustic cocktail, CO2 hit, OOG diver...). NoTox is fine if you're at deco with loads of time to validate your gas but not good if you're on a rebreather and need your bailout now.

The sidemounter's fix to floaty stages is to pull the waist mount forwards towards the waist buckle. Sidemounters use sliding D-rings but this is difficult if you've a single fixed D-ring on the LHS used for clipping SPGs & stages. A leash only uses a single fix point so the stages are free to move wherever they like; up down left right.

One thing some people do is to mark the MOD on some tape on the bottom of the regulator mouthpiece. Even taping over rich gasses so they cannot be used in error. Think Steve Martin shows this on his sidemounting courses.

 

[Luis H]

I have couple of more subjects related to my setup for these dives. I was going to take a long pause in light of Bryan’s passing, but I decided to post since I had most of the writing done from before.

One subject, is the performance improvements I have been working on, by optimizing the venturi flow (including the new flow diverter in the DSV and the improved venturi adjusting blocks). My last planned subject will be the cross-over connection and how I controlled my back-gas (using pneumatic lock).

When I designed the HPR second stage part of the design considerations was flexibility and adjustability, as well as backwards and forward compatibility with vintage DAAM, RAM and the future 2 stage replacement (now known as the Argonaut Kraken). At the time we didn’t have a mouthpiece with a flow diverter, therefore we had to limit the amount of venturi flow assistance, but I always planned on incorporating a new mouthpiece with a flow diverter. I needed the ability to adjust the mount of venturi flow.

From another post:

There is a reason why I called it the second stage HPR (High Performance Regulator).

With the HPR you have the ability of making three independent adjustments: the lever height, the spring tension (which can control cracking effort), and the amount of venturi assistance.

I am just about to write some more details on how to adjust all three, but here is a little advance information. I have shared most of it in other posts, but I will add more.
Note: I just designed a new flow diverter for my DSV design, that allows me to take full advantage of the maximum venturi flow.

1) The lever height adjustment is kind of intuitive. You use the nut on the seat carrier to adjust it.

2) The spring tension can be reduced by backing (unscrewing) the HPR body in increments of half turns (180 degrees). Cracking effort is fine-tuned by balancing the spring pressure against the IP. In the Argonaut, I typically adjust the cracking effort to about 0.6 inWC (to 0.7inWC max). Anything lower and it will free-flow when the top edge of the exhaust valve is higher than the center of the demand valve.

3) The venturi flow can be adjusted, by changing the ratio, of the amount of air in the jet pointing down the horn, to the amount of bleed-air going into the can. The adjustment is done by blocking the side bleed-air ports to the desired amount. I will expand on this.

From the early design stages I tried to make the HPR a very adjustable second stage with ability to push the performance...

Now we have my new DSV and I now have optimized the flow diverter for the DSV. Therefore, I can push the limits on the venturi flow assistance.

Below are pictures of my new flow diverter. The new flow diverter does not allow any blow-by past the mouthpiece, therefore allowing the maximum possible venturi flow assistance.

The flow diverter actually seals around the perimeter of the inner tube and it has a vane directing all the flow to the diver. The designed called for an interference fit, therefore to assemble it into the DSV it required a flexible material. The 3D printed units are made out of TPU (a flexible plastic, almost like an elastomer).

Inlet side of DSV and flow diverter.

Exhaust side of diverter.

Some 3D printed flow diverters, before I installed them.

Here are pictures of my new 3D printed bleed-air port blocking device. Notice they can be turn around to allow more or less (down to zero) bleed-air out of the side ports.

I am using a tapered hole and counter sunk screws. The holes are offset just enough so that tightening the countersunk screw creates wedge effect due to the ramp in the hole and the screw. When tighten the screws, the stop pushes sideways against the second stage locking and sealing the bleed-air ports.


This is the configuration I use for maximum venturi flow. Notice that both bleed air ports are fully blocked. The notched ramps are facing out.

This is the configuration I would use with the old stock flow diverter to provide a manageable venturi flow. It is not the optimal, but it is good for must divers. Notice the one open bleed-air port.

This is looking into the horn. Notice both bleed air ports are fully blocked.

This configuration provides exceptional venturi flow. This configuration can only be used with the new flow diverter installed in the DSV. With any other mouthpiece, the venturi flow will produce a lot of gas blow-by and out the exhaust. With the vintage curve mouthpiece (no flow diverter) it would often produce an uncontrollable free-flow out the exhaust.

With the new flow diverter, the combination makes for a sweet breathing regulator at any depth.

Next, I will talk about the cross-over connection and how I controlled my back-gas (using pneumatic lock).