i've seen twin set 7l tanks, i wonder, why would you not just use a 15l single tank?

[00wabbit]

Inverted doubles makes no sense to me. How do you get your gear on and off?

I dive inverted doubles myself, but it's called a rebreather.

You have a valve protector on them so you can sit them down inverted.

 

[DevonDiver]

This is a really good blog article about inverted doubles: Nigel's twinset rig

Personally, I think that sidemount surpasses inverted rigs, for those who can't reliably perform shut-downs.

 

[00wabbit]

This is a really good blog article about inverted doubles: Nigel's twinset rig

Personally, I think that sidemount surpasses inverted rigs, for those who can't reliably perform shut-downs.

Sorry to hijack this into an inverted thread, but I am right in the middle of this line of thinking.

I just started doubles and cant quite reach the valves. Yes I can stretch etc and get better, but in an emergency I would sure like to be able to get those quickly. I found the article on inverted doubles and that seemed like a good idea, but now I am pretty sure SM is the way to go for what I want. I am just concerned about getting back on the boat, but I'm a big guy and the tanks on the side shouldn't affect me as long as the ladder has width for me.

 

[Glenn08]

I am also wondering about trying sidemount, but my local shop doesn't do rental equipment sidemount training. And I'm not ready to buy a full sidemount rig without trying it first.
If you search Akimbo, he has some nice pictures of inverted twin tanks.
I switched to valves-down to reach the valves more easily.

 

[LowDrag]

Something one diver I know has on his tech rig is a knob & handle that comes down over his shoulder so he can open or close his valves without having to reach over his shoulder. I don't if it is right, wrong or otherwise just that that is what he does. I don't even know what to call it or I would put up a picture of it.

 

[Jim Lapenta]

It's a valve handle extension. OMS made/ makes them. They are also derisively known as a slob winder.

Sent from my DROID X2 using Tapatalk 2

 

[mala]

Something one diver I know has on his tech rig is a knob & handle that comes down over his shoulder so he can open or close his valves without having to reach over his shoulder. I don't if it is right, wrong or otherwise just that that is what he does. I don't even know what to call it or I would put up a picture of it.

its a slob knob.
only does the isolater and not the first stage valves.

on the 2 x 7ltr front I always thought it was a waste of time unless the tanks where 300 bar and even then its not to good.

I go for the indy doubles-then at least if you cant close the valve you only loose 1 tank.

 

[Hickdive]

Something one diver I know has on his tech rig is a knob & handle that comes down over his shoulder so he can open or close his valves without having to reach over his shoulder. I don't if it is right, wrong or otherwise just that that is what he does. I don't even know what to call it or I would put up a picture of it.

We call them a slob knob. Custom Divers still make them.



A bit of a misnomer because of the three valves on an isolation manifold the centre tap is easiest to reach.

I have seen a guy with slob knobs on all three taps.

 

[DevonDiver]

Slob Nobs are (were?) very popular in the UK, when I used to dive there. I remember hearing lots of talk about a high failure rate with them. I don't have first hand experience of that - I never used one.