User avatar
Bryan
Plank Owner
Posts: 5206
Joined: Fri Jun 24, 2005 11:40 am
First Name: Bryan
Location: Wesley Chapel Florida
Contact: Website

Re: Argonaut Mix-mount or Tri-mount… as opposed to side moun

Sun Jul 09, 2017 2:18 pm

tbone1004 wrote: I'd have no problem diving trimix on a double hose on doubles with a cheater bar if I can find one. I haven't found one that i like yet and haven't seen where the WMD's are available in the US. Would be nifty on a set of 72's
Great......When you do it, have another diver shoot a 3-5 min video of the highest quality they can showing your rig all the way around and we will edit it down and make it the front page video for VDH.

The WMD manifolds are at a price I'm not sure would sell great for me but getting them is no problem.
Doing it right should include some common sense, not just blindly following specs and instructions. .Gary D, AWAP on SB

User avatar
luis
VDH Moderator
Posts: 1536
Joined: Thu Jun 30, 2005 9:28 pm
First Name: Luis
Location: Maine

Re: Argonaut Mix-mount or Tri-mount… as opposed to side moun

Sun Jul 09, 2017 2:26 pm

tbone1004 wrote:
Bryan wrote:
slonda828 wrote:I will pay you to put up pictures of that in the DIR forum on Scubaboard.
He put it in the sidemount section at SB.....I think the whole concept is just so far out of the bounds they call acceptable that they don't know how to comment. It got some accolades and a few questions but I"ll bet any amount of $$$ that there were PM's flying around with people going WTF is this guy doing......
I got a couple of those wtf pm's. too many issues with the UTD manifold block is part of the problem. I'm currently diving sans secondary/octopus as I hate the golden triangle nonsense and am trying to figure out how best to run it without offboard tanks.

I'd have no problem diving trimix on a double hose on doubles with a cheater bar if I can find one. I haven't found one that i like yet and haven't seen where the WMD's are available in the US. Would be nifty on a set of 72's
Can you expand on the issues with the UTD manifold block? Are they specific to their manifold design? If you like, you can email me directly.


Close to 10 years ago when I did my deco procedures class I used a Sherwood doubles manifold with two independent regulator outlets. It is a great manifold with a center outlet that works great with a DH and a second outlet to have an independent regulator.

I have used that setup for a number of deep deco wreck dives with several modern DH regulators.

Here is a thread in SB of when I was diving that setup.
https://www.scubaboard.com/community/th ... ix.256559/

It is too bad that the PhotoBucket pictures are now out of reach.

I still have that set of doubles (and several other small doubles with the same manifold). The issue with the setup is traveling with it is out of the question. That is the primary reason for my mix-mount setup.

After using the mix-mount setup I am actually very pleased with how it feels in the water.

The only issue with any of this setups is the out of the water weight of multiple tanks. I can split the mix-mount setup at the water’s edge, but then I still have to come back and pickup the cylinders.

Note: The Sherwood manifold isolates the two regulators independently, but does not split the gas supply of the two cylinders. After doing a lot of reading and studying the modern isolation manifold (that isolates the two cylinders) I am not a believer on the miniscule advantage of such a manifold.

I can expand on the reasons why I find the modern isolation manifold potentially counterproductive, but that should be in a different thread. It would be a longer post.
Luis

Buceador con escafandra autónoma clásica.

User avatar
Ron
Site Admin
Posts: 1650
Joined: Mon Oct 20, 2008 5:51 pm
First Name: Ron
Location: Puget Sound, Washington
Contact: Website

Re: Argonaut Mix-mount or Tri-mount… as opposed to side moun

Sun Jul 09, 2017 2:54 pm

I would like to hear engineering reasons for why the modern isolation manifold is counterproductive, if you would be willing to start a thread about that. As a guy who got into technical diving in the last 10 years, the isolation manifold or sidemount are largely viewed as the only ways to technical dive with standard gear and procedures on a team.

Really, the only thing holding me back from doing more technical things than I've already done with my doublehose is that nobody will dive it with me unless I have standard redundancy with an isolation manifold. When I dove the hangar deck of the Oriskany, I did it in standard back mounted doubles because nobody would let me use a doublehose because I would've had to use a non-isolated manifold and my teammates would not agree to accept the risk.

If you can present a reason, backed up with data, for why an isolated manifold is not a requirement I would like to read it.
The impossible missions are the only ones which succeed. -JYC

tbone1004
Lung Diver
Posts: 64
Joined: Tue Aug 26, 2014 9:44 am
First Name: Tom

Re: Argonaut Mix-mount or Tri-mount… as opposed to side moun

Mon Jul 10, 2017 8:33 am

Luis, not sure if it's just me, but I keep seeing something saying please update your account to enable 3rd party hosting. Has an analog gauge with 3rd party hosting usage at 100% from photobucket.... Any chance you'd switch those pix over to facebook so we can see them again?

On the UTD manifold issue. Here are the main ones for sidemount that are obviously completely somewhat unrelated to double hose diving :D
The concept itself is great, however like has been said, it is an equipment solution to a skills problem, and trying to force a paradigm from one gear configuration into another. No different than BSAC refusing to allow primary donate period *unless you have training in primary donate from another agency that it recognizes, which hilariously GUE is not one of...* because you can't primary donate on a rebreather. UTD believes so strongly in primary donate and always donate what you are breathing that they forced that backmount principal into sidemount. Best part of that is that when you are doing big open circuit cave dives, like expedition level, you are almost never on your backgas to begin with.

Tanks still have to be "switched". The IP imbalance that is going to happen will cause a bias on one tank vs the other if they are both open. As such, you have to fully shut down and ultimately purge one tank unless you use an inline shutoff. This is clunky and annoying. There is no provision for some sort of switch block like you see on a Kirby Morgan helmet or some rebreathers.
QC connectors are required in order to keep the manifold system attached to the bcd and the tanks separate. These are big, clunky, and expensive for the ones that allow breathing volumes through.
Almost of the leak points are still behind your head where you can't see them and up until recently there was no way to isolate one side from the other in the event of a second stage or LPI failure.


For the vintage double hose. Anyone have one of those old sherwood manifolds that they'd be willing to loan out? maybe a set of bands if they use a non-standard doubles spacing? Will set up a set of doubles and get deep this summer

User avatar
luis
VDH Moderator
Posts: 1536
Joined: Thu Jun 30, 2005 9:28 pm
First Name: Luis
Location: Maine

Re: Argonaut Mix-mount or Tri-mount… as opposed to side moun

Mon Jul 10, 2017 7:27 pm

I am sorry about the pictures. It is a Photobucket thing. You can still see the pictures in some of the ScubaBoard threads.

https://www.scubaboard.com/community/th ... nt.545832/
https://www.scubaboard.com/community/th ... nt.545511/


Thanks for the information on the UTD system.
Luis

Buceador con escafandra autónoma clásica.

User avatar
tripplec
Master Diver
Posts: 283
Joined: Thu Mar 28, 2013 1:44 am
First Name: Chris
Location: Coos Bay Oregon
Contact: Website

Re: Argonaut Mix-mount or Tri-mount… as opposed to side mount

Sun Jan 28, 2018 4:34 am

Im verry intrigued Luis. About three years ago I was contemplating tying two first stages together through a lp hose just out of curiosity. Does it draw air equally from left and right tanks keeping you balanced? And can you get the 135 ip set with just a typical dial gauge like the bc hose ip checker, or did you have to get both first stages right down to almost exact with a high quality exspensive guage?

User avatar
tripplec
Master Diver
Posts: 283
Joined: Thu Mar 28, 2013 1:44 am
First Name: Chris
Location: Coos Bay Oregon
Contact: Website

Re: Argonaut Mix-mount or Tri-mount… as opposed to side moun

Sun Jan 28, 2018 4:45 am

Ron wrote:
Sun Jul 09, 2017 2:54 pm
Really, the only thing holding me back from doing more technical things than I've already done with my doublehose is that nobody will dive it with me unless I have standard redundancy with an isolation manifold. When I dove the hangar deck of the Oriskany, I did it in standard back mounted doubles because nobody would let me use a doublehose because I would've had to use a non-isolated manifold and my teammates would not agree to accept the risk.
You can dive non isolated with me Ron next time I'm up there. My aunt criticized me once for not being "safe". She said "people have died doing that without proper gear and training". I told her "there are many Doria plates on eBay from people with no training. Ya some died, but people today are spending thousands on 'tech' gear, more thousands on training, and they still die."

User avatar
luis
VDH Moderator
Posts: 1536
Joined: Thu Jun 30, 2005 9:28 pm
First Name: Luis
Location: Maine

Re: Argonaut Mix-mount or Tri-mount… as opposed to side mount

Sun Jan 28, 2018 11:42 am

tripplec wrote:
Sun Jan 28, 2018 4:34 am
Im verry intrigued Luis. About three years ago I was contemplating tying two first stages together through a lp hose just out of curiosity. Does it draw air equally from left and right tanks keeping you balanced? And can you get the 135 ip set with just a typical dial gauge like the bc hose ip checker, or did you have to get both first stages right down to almost exact with a high quality exspensive guage?

Getting it to draw from two first stages would only require that the IP in both first stages is close to each other. Now, getting it to draw the exact same amount from both first stages (during the duration of the entire dive) is probably impractical.

It is more than just the IP. The IP is just one number for the pressure that closes the first stage valve. The pressure when the valve actually opens and starts delivering air is a bit lower and it is kind of hard to measure due to the flow dynamics.

Then there is flow resistance. Even if both first stage valves open and closed at the exact same pressure, with both valves open at the same time, the flow resistance will not be the exactly the same from both air sources.

Note: with a set of double tanks (even if the flow resistance is not perfectly balanced) the tank pressure will equalize between the two tanks between breaths. The same will not happen with this system.

The difference between the two air sources may or may not significantly affect how much gas comes out of each supply. I haven’t actually tested that because I prefer to actually control how much gas I have in each supply. I have inline valves to close or open each source. And I have pressure gauges on each air supply.

It is not like I have to change regulators (out of my mouth) like when using independent doubles. All I have to do is slide the shut-off valves that are right in front of me. Even if I close one before I open the other one, I have the gas supply on my back. The transition couldn’t be any easier or smoother. It is just nice to be in control and be able to monitor which cylinder I am breathing out of, without ever having to change my mouthpiece.

Maybe next summer I may test the set up with both side tanks open simultaneously for the entire dive to see how well balanced they are (or are not). When I had them both open on my previous dives, I didn’t leave them open long enough to notice if more gas was coming out of one or the other. It was just not that important to me, to know that.
Luis

Buceador con escafandra autónoma clásica.

User avatar
tripplec
Master Diver
Posts: 283
Joined: Thu Mar 28, 2013 1:44 am
First Name: Chris
Location: Coos Bay Oregon
Contact: Website

Re: Argonaut Mix-mount or Tri-mount… as opposed to side mount

Sun Jan 28, 2018 1:37 pm

Thank you. That all makes perfect sense. My dive buddy and I have been discussing using sling tanks, this idea sounds like a practical (for someone that is comfortable playing with their dive gear), way to used my pram. And like you said, still have many redundancies. Thanks for the writeup.

User avatar
tripplec
Master Diver
Posts: 283
Joined: Thu Mar 28, 2013 1:44 am
First Name: Chris
Location: Coos Bay Oregon
Contact: Website

Re: Argonaut Mix-mount or Tri-mount… as opposed to side mount

Sun Jan 28, 2018 2:39 pm

I read through your second post on scuba board. I cant believe you didnt get the "your gona die". Did you have to relocate any weight to stay trim? I use a belt and it works fine between single and double back mount, but I have no experience yet with side mount.

User avatar
tripplec
Master Diver
Posts: 283
Joined: Thu Mar 28, 2013 1:44 am
First Name: Chris
Location: Coos Bay Oregon
Contact: Website

Re: Argonaut Mix-mount or Tri-mount… as opposed to side mount

Tue Feb 06, 2018 1:46 am

Can I ask where you got the quick disconects? Saw some on piranha with the twist locks. And those short hoses on the side tank with the female end, you recrimp the ends yourself or do they make second stage hoses that short?

User avatar
luis
VDH Moderator
Posts: 1536
Joined: Thu Jun 30, 2005 9:28 pm
First Name: Luis
Location: Maine

Re: Argonaut Mix-mount or Tri-mount… as opposed to side mount

Tue Feb 06, 2018 7:08 am

Piranha has the short hoses and the quick disconnects. He also has the short HP hoses for the pressure gauges.
Luis

Buceador con escafandra autónoma clásica.

Return to “Modern Era Double Hose Diving”

Who is online

Users browsing this forum: No registered users and 1 guest