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Hi guys, continuing the earlier posts regarding redundancy, I think i'm going to go for the twin-7's route, but need to know the best way of configuring the equipment. I'm not going to be diving extremely deep, and i'm not going to be doing speciality stuff like wreck penetrations or cave diving...

My present thoughts are:

Twin 7's (manifolded) mounted on my Buddy CommandoTD
My current 1st stage/DV (ATX40) on the right cylinder with my suit inflator.
A new ATX40 1st stage with my current AAS (ATX40), BCD inflator and pressure guage on the left cylinder.

As I see it I would have basically the same kit configuration as I have now - but with the redundancy/extra air i need to do the slightly more challenging dives (upto 30m).

I would plan to upgrade to a wing at some point in the near future also (those who told me only six months ago to get a wing to start with  
)

Is there anything inherently wrong with this configuration? As I see it i get the benefits mentioned above, and my buddies/club members will be seeing a configuration they're used to dealing with.

While i'm thinking about it - if you have to isolate the left cylinder and call the dive, how do you know how much air you have available for your ascent/deco? Simply that you were already carefully monitoring your air supply???

Thoughts appreciated.
 

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Discussion Starter · #3 ·
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From my researh (Dom's website - again!) you isolate the regs and not the "cylinder" as such? That way you can use the contents of both cylinders off a single reg even when the other is isolated?

The situation i was thinking of was a burst hose/o-ring that meant the reg had to be isolated - if it's the one with the guage on you have no way of reading your contents...? I'm still learning - i too am currently a single cylinder numpty diver!
 

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<font color='#728FCE'>This was the type of configeration used by a lot of people before wings became popular & without a manifold.

I am looking into putting twin 7l on a Commando TD, had to get rid of the wing and twin 10s as they were to heavy. I have dived with 2x12l on this jacket and it handled it well. With the manifold, get used to using it in the pool and going through shut down drills and then go diving.

Send me a PM and we can compare notes and have a dive.
 

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Just my thoughts...

Twin 7's (232 or 300s)  just out of interest.

I tend to use my suit more than my wing so I bring my suit inflator off the same post as my spare reg and my jacket off the post with my primary.   Throughout the dive I am effectively using both 1st stages so hopefully if one fails I would spot it reasonably quickly.

There was another reason why I set mine up like this, but I can't for the life of me remember what it was  


I only have a guage on one post and in the event of having to shutdown then I would know I had enough air in the remaining cylinder for the ascent and safety stop for the following reason.

Plan the dive as if you had a single 7,  What is the minimum amount of air in that 7 for you to ascend and do a safety stop ?   Lets say after all the calcs it equates to 560l (80 bar )  then you should plan to finish your dive and start your ascent when your guage registers 80bar.  If one side goes TU after that you still have enough in the remaining cylinder.  (This is based on you having to isolate at the manifold not the post and assuming one side is completely unavailable).

Hope that is clear,  sorry if it is a bit rushed.

Daz
 

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One other thing to remember - Apeks regs can't be swapped from right to left-handed, so you'll need to bring your secondary reg behind your neck and on a necklace/bungy under your chin. This may mean you'll need a longer hose, and some may say you should have a longer hose for your primary anyway, but I don't and it works fine for me - in an OOA situation, pass primary reg to buddy and breathe from reg under chin (which is close to hand and easily reached).
HTH
Martin
 

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Discussion Starter · #7 ·
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Hi Martin,

As my AAS (octopus) is mounted on the left side of the 1st stage, it could still be routed to the left couldn't it? Why would it need to be routed behind my neck? (Unless i did want to necklace it).

At present my config is totally "BSAC", not saying it's the best way of doing it but we're all drilled at moment to look for octopus on left...
 

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[b said:
Quote[/b] ]A new ATX40 1st stage
I hate to be pedantic, but there's no such thing - the ATX range are modified TX second stages. The first stages remain the same, either DS4 or DST.

I personally recommend you get the DS4, which is the non-turret version. You don't need the swivel on a twinset.

Your described hose routing is pretty much the same as mine, only I have my LP hoses the other way around, with the wing on the main and the drysuit on the left. Mainly because I put more air into the suit on descent than the wing, so it spreads the load a bit.

(There's also the DIR argument that if you've handed over your main and the backup doesn't work, you can breathe off the wing inflator if it's on the right post...)
 

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[b said:
Quote[/b] ]Why would it need to be routed behind my neck?
Because it's a twinset. It's there for redundancy. That means you have to be able to breathe off BOTH cylinders. You have to configure your DVs so you can breathe off both of them.

A single + octopus rig has two DVs. One is yours, the other is for your buddy if something goes wrong.

On a twinset, you have two DVs. One is yours, the other IS ALSO YOURS if something goes wrong. If you can't breathe off your backup DV, you might just as well use a single 15 instead. Less to go wrong, and its cheaper too!

That's why the long hose is so popular - you can have your backup under your chin where it's dead convienient for YOU, your primary is in your mouth, dead convenient for YOU, and yet you still have a DV that's convenient for your buddy without having to have more than two DVs
 

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Discussion Starter · #10 ·
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A whole hour and a half! What took you so long Dom?  


OK, I understand the thinking and you're probably right - it's just that it doesn't seem too much of a hindrance to me to take my octopus from the left where it's clipped to my BCD and stick it in my mouth. That could of course change at 30m - especially as i've never had it happen to me before - so hard to say. I take on board what you're saying though.

So with a DS4, the best way of routing my AAS would be to the right and then under my chin... What about the length of hose? My AAS hose is pretty long, couldn't that be an issue...?
 

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[b said:
Quote[/b] ]What took you so long Dom?
Work. They may stop paying me if I don't look busy enough


[b said:
Quote[/b] ]it doesn't seem too much of a hindrance to me to take my octopus from the left where it's clipped to my BCD
It might not be too hard. But could it be made any easier? THAT is the question.

Anyway... check it out - I thought the same until I tried to use my octo underwater, and whilst it was do-able, the hose was so bent that it pulled to one side and gave a permanently wet breathe.

With the extra distance involved on a twinset, it might be better, it might be worse...

[b said:
Quote[/b] ] So with a DS4, the best way of routing my AAS would be to the right and then under my chin...
<biased mode> That's the best way regardless of what 1st stage you're using</bias>
I'd hate to have my backup DV configured to be upside down unless re-arranged. But it's your rig, if you're happy with it that way, then go right ahead with it clipped off like a normal octopus.

[b said:
Quote[/b] ]What about the length of hose? My AAS hose is pretty long, couldn't that be an issue...?
AP Valves part AP50B or SAP part 5046 - re-useable hose ends. Cut any LP hose you have to any length you like. Every LP hose I use has a re-useable fitting on it. They're great


My backup DV was originally over-long, I had to route it under my arm. Major PITA when it was time to breath off it, had to re-arrange it first. Now it goes over my shoulder because the hose is just the right length.
 

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I dive with twin 7 cylinders with apeks regs (tx100). My current setup has done 100+ dives with very little change. I've got my drysuit and main reg on my right shoulder and my wing inflation, console and AAS on my left.
The occy has a 2m hose on it, which is great. 2m hoses are not just for cave divers. It means that you can easily wrap it round your neck so the hose doesn't pull across the front of you and you get the hose on the right side. If you do need to donate air it is a lot easier for the er... victim as the length means its not going to get yanked out of their mouth again in the chaos that ensues during a real out of air incident.
If you are monitoring your air as you should and you do have a freeflow and have to shutdown the side with the console on it you should have some idea how much air you have, and my diving practice is to abort the dive (what happens if your AAS free-flows !?).
Many divers have a gauge on both cylinders which allows you to monitor your air and also if you wished to close the manifold and dive them as independants... but some would argue that if the manifold is open a second gauge is another point of potential failure.
 

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Discussion Starter · #13 ·
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hmmm, going the route of AAS under chin then, on shortened hose pretty much dictates you have to go the long hose route on your main dv... are there recognised options for the long hose or is the DIR/Hogarthian method the one to go for? I'm not 100% sure a long hose is for me - i know there's arguments for it... still...

Mongoose, how do you route your AAS?

Thanks all - this is giving me plenty of good stuff to think about...
 

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Two main options for the long hose primary - Hog/DIR loop, or stuff it.

Stuff it meaning you coil it up neatly and put it somewhere tidy, of course..

I don't like the coil option, as it's too faffy - the hog loop can be done in seconds, and seconds count when you're on a RIB and suffer from seasickness


Where are you based? I'm sure there's someone on this board that's near enough for you to have a go on their twinset...
 

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My tuppence worth:

Basically agree with pretty much all the replies above:
definately get yourself the DS4 it's also a little cheaper than a DST at ~£70 (DWH). I've got one of each, due to the same reasons of kit evolution.

Also you do indeed want to have your secondary coming over your right shoulder, (and yes your current octo will be long enough to use over your right shoulder)  in a FUBAR you don't want to be farting around  to get it sorted into a position to breathe off.  

An extra long hose for your primary will only cost you about £20-£30 depending on whether its 1.5 or 2m and your LDS's, worth thinking about.

See how you get on with reaching your valves and if like me it's not easy enough for comfort, consider inverting. The best reason I would give is that in a complete-double-DV-FUBAR, unlike the situation Dom described as "the DIR argument", you can very easily turn an inverted valve on/off for every breath, far far more preferable to me than breathing off your BC (which if you survive the diving incident could very well leave you with a nasty lung disease).

Speaking of inverts - Daz, it appears you and I have the same configuration: have you kept your original hoses for BC & secondary? I've found that my octo hose is ok coming from the RH side in front of me and is just long enough to necklace. The BC hose is ok too as my inflator comes under my arm and is neatly bungeed to the harness. might consider custom hoses in the future but it would be pretty much a cosmetic issue.

Chee-az
Steve
 

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Discussion Starter · #16 ·
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I'm in Chester.

Inverted twins... Would be very nice - providing i had a nifty way of protecting the 1st stages on the club RIB!

The reaching the valves issue is one of concern - i've got a cordura suit that's quite heavy - won't know until I try though! Will try out twin configuration at SDS before i flash the plastic to make sure i can reach to do all the shutdowns in the drysuit...
 

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I've got Custom Divers valve guards to protect my pillar valves, mine were SH off Andy2Tanx , they're ~£90 brand new, but Jay has a link somewhere to a manufacturer who makes a different model of VG but for half the price, not as aesthetically pleasing but who cares for that price

Anyhoo, you can start "right way up" then progress to inverted config later on if you so desire, so there's no need to splash all the cash straight away
Chee-az
Steve
 

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[b said:
Quote[/b] (Steve W @ July 24 2003,16:23)]My tuppence worth:

Basically agree with pretty much all the replies above:
definately get yourself the DS4 it's also a little cheaper than a DST at ~£70 (DWH). I've got one of each, due to the same reasons of kit evolution.

Also you do indeed want to have your secondary coming over your right shoulder, (and yes your current octo will be long enough to use over your right shoulder)  in a FUBAR you don't want to be farting around  to get it sorted into a position to breathe off.  

An extra long hose for your primary will only cost you about £20-£30 depending on whether its 1.5 or 2m and your LDS's, worth thinking about.

See how you get on with reaching your valves and if like me it's not easy enough for comfort, consider inverting. The best reason I would give is that in a complete-double-DV-FUBAR, unlike the situation Dom described as "the DIR argument", you can very easily turn an inverted valve on/off for every breath, far far more preferable to me than breathing off your BC (which if you survive the diving incident could very well leave you with a nasty lung disease).

Speaking of inverts - Daz, it appears you and I have the same configuration: have you kept your original hoses for BC & secondary? I've found that my octo hose is ok coming from the RH side in front of me and is just long enough to necklace. The BC hose is ok too as my inflator comes under my arm and is neatly bungeed to the harness. might consider custom hoses in the future but it would be pretty much a cosmetic issue.

Chee-az
Steve
Firstly for Justin

http://www.ritherdon.co.uk/shop.as....uipment

Steve,

Sounds exactly the same even the routing of the necklaced spare and the LP wing inflator.

But must admit,  I have just got a 5ft reg hose for my spare (4ft would have been enough but I figured it would double as a spare long hose for my primary) and a custom LP hose for the wing.  I am thinking of routing them either up the backplate and over the shoulder as required or I might even route them between the backplate and cylinders.

To be honest,  I got on fine with the hoses as were but the necklaced DV was only just long enough and I would not have wanted to lturn my head too much and the LP inflator hose sometimes pushed the wing inflator under my arm if it twisted the wrong way.

Regarding the primary routing,  5ft hose across the body, over the shoulder, behind the head and round in my gob.  5ft was more than enough for me.

Cheers,
Daz
 

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Discussion Starter · #19 ·
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this is a proper can of worms... another consideration is that i take my kit abroad, so the current config is perfect for diving while on holiday with single cylinders... and i don't really want to be buying new DV's to go on long hoses just yet...!!

hmmm...
 

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[b said:
Quote[/b] (Justin Owen @ July 24 2003,19:28)]this is a proper can of worms... another consideration is that i take my kit abroad, so the current config is perfect for diving while on holiday with single cylinders... and i don't really want to be buying new DV's to go on long hoses just yet...!!

hmmm...
Well you don't have to buy new DV's.  I still have my normal length inflator hose and a normal length regulator hose.

When I am going abroad, I just setup my rig with a normal inflator, normal octopused DV hose and 5ft long hose for my primary.

If you have a hose the correct length for your necklaced backup and a 5ft hose for your primary you can use both of these on a single first stage when diving on singles.  Just hog loop the 5ft hose like you would with twins.

Daz
 
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