Not understanding the long hose thing

[Eric Sedletzky]

I used to dive with a long hose and bungeed second running over my shoulder.
I found for open water diving in Northern California the long hose became more of a nuissance than an asset,
and an entaglement hazard with bull kelp (sometimes) but more with feather boa kelp with it running behind the neck.

I have since changed the setup and now run two octo length hoses under my arm with one bungeed. With this method I have no hoses running over my shoulders (except the LPI sometimes) and I am more streamlined than the standard DIR-GUE long hose configuration.
Not all people feel that the DIR configuration is the end all and best configuration for every situation. Some of us have moved foreward from this frozen thinking and have figured out stuff that works better.
The octo length still provides enough hose for an OOA diver to comfortably share air. I also run it off the end port of a MK 20.
All this is only if I'm buddy diving.
If I'm solo diving and doing a shallow reef dive in the 30 to 50 foot range all I use is a MK 2 with one second stage and an SPG.

Lately I have been using my double hose though and the whole issue is a moot point with this piece of gear.

Because all vintage divers are wierd, don't you know.
So are minimalists.

 

[RJP]

[-]Most[/-] A few people use a 5' hose for single tank config, while the majority of long hose divers use a 7' hose for both single and double tank configs.

Fixed it for you.

 

[fishoutawater]

Wow. I sure didn't mean to open up a major can of worms, but it appears that there alomost as many opinions as there are posts on the subject of hose length.

Anyway, my new Miflex hose showed up last night, and I tried to install it onto my Mares MR22. But I discovered that the Miflex has has a 3/8" male fitting, and the port in my 1st stage where my primary reg is installed is 1/2". My heart sank. But then I realized the other LP port on the same side (where my octo is installed) is a 3/8". So I got all cornfused.
Then I got out the box my reg came in, and discovered a 3/8" male to 1/2" female adaptor. TADAAA! So now I could install my octo in the rear port, and the primary in the fwd port. Screwed it all together, stuck it on my tank and cracked the valve. Works fine. And now that my primary is in the forward 3/8" LP port, my hoses route much better. The hoses don't cross over each other anymore. Much more ergonomic. And the original hose, with the 1/2" male fitting (and super stiff) that only fit in the rear LP port, is now stored in the box.
What I can't figure out, is why there is a 1/2" port in the first stage in the first place. Is there some low pressure device requiring a 1/2" port and a super stiff hose that I don't know about?
Anyway, I really like my new floppy 30" Miflex hose. Haven't had it in the water yet, but I can now turn my head and feel somewhat human again! Although later on, I may switch to a 36" or 40" hose with a 90 degree fitting so I can run my primary under my arm instead of over my shoulder. And add another 90 to my low profile octo so I can bungee it around my neck.

 

[RJP]

Anyway, I really like my new floppy 30" Miflex hose. Haven't had it in the water yet, but I can now turn my head and feel somewhat human again! Although later on, I may switch to a 36" or 40" hose with a 90 degree fitting so I can run my primary under my arm instead of over my shoulder. And add another 90 to my low profile octo so I can bungee it around my neck.

I think you'll find that with the proper length Miflex hose you won't need 90deg adapters.

Good diving!

 

[fishoutawater]

I think you'll find that with the proper length Miflex hose you won't need 90deg adapters.

Good diving!

True, I may not NEED 90 degree fittings, but it's a streamling thing. Plus, it's just one of those aviation type things. Been an aircraft mechanic/inspector for 25 years, and one of the general rules about running hoses, is to always use a hard fitting (whether it be a straight 180, 45 or 90) to get the hose pointed in the general direction you want it to go. You don't want to depend on hose flex to make tight bends. Granted, in the primary, we're not looking at 5000psi hydraulics, but it's still a general rule in any system.

 

[UCFKnightDiver]

from what Ive heard, and seen hose strain on the miflex hoses is practically non existent, or at least greatly reduced than that of normal hoses, probably dont need a 90 as its just another failure point thats really not needed

 

[Nemrod]

from what Ive heard, and seen hose strain on the miflex hoses is practically non existent, or at least greatly reduced than that of normal hoses, probably dont need a 90 as its just another failure point thats really not needed

As an IA/A&P like the OP, a bend in a hose is considered a failure point in our training.

N

 

[UCFKnightDiver]

True, I may not NEED 90 degree fittings, but it's a streamling thing. Plus, it's just one of those aviation type things. Been an aircraft mechanic/inspector for 25 years, and one of the general rules about running hoses, is to always use a hard fitting (whether it be a straight 180, 45 or 90) to get the hose pointed in the general direction you want it to go. You don't want to depend on hose flex to make tight bends. Granted, in the primary, we're not looking at 5000psi hydraulics, but it's still a general rule in any system.

As an IA/A&P like the OP, a bend in a hose is considered a failure point in our training.

N

I seriously doubt that 130~ or so psi is putting much strain at all on the miflex hose considering its propensity to bend and move freely, just saying.... Also you're adding one or more orings with a 90 deg elbow/swivel

 

[fishoutawater]

Not using an o-ring swivel. Just a 90 degree hard fitting. Hard fittings are used everywhere in aircraft. They're not considered failure points at all. Just parts of the system. You're right about intermediate pressure not putting much strain on the hose. But without the ninety degree fitting, the hose would come straight out of my reg, a sharp bend down towards my arm pit, then bend again in an opposite direction sweeping around my back and up to my first stage. With the fitting installed, the hose forms basically one big bend all in one axis. So effectively, with the fitting, I have one big U bend. Without the fitting, I'll have an opposing S bend which fights itself and my head turning efforts. One loose bend is better than two tighter ones.
http://www.gatespowerpro.com/resources/doclib/HoseRoutingTips.pdf

 

[Nemrod]

Not using an o-ring swivel. Just a 90 degree hard fitting. Hard fittings are used everywhere in aircraft. They're not considered failure points at all. Just parts of the system. You're right about intermediate pressure not putting much strain on the hose. But without the ninety degree fitting, the hose would come straight out of my reg, a sharp bend down towards my arm pit, then bend again in an opposite direction sweeping around my back and up to my first stage. With the fitting installed, the hose forms basically one big bend all in one axis. So effectively, with the fitting, I have one big U bend. Without the fitting, I'll have an opposing S bend which fights itself and my head turning efforts. One loose bend is better than two tighter ones.
http://www.gatespowerpro.com/resources/doclib/HoseRoutingTips.pdf

What he said.

Different industries have different ways of looking at things, this is ours.

I agree, a large radius bend in a flexible scuba LP hose is not a huge concern.

A 90 degree fitting such as the DiveRite would be preferable to repeatedly kinking a standard LP hose, the Miflex, I have no real experience with in this application.

N