Advice Please

[Daz217]

I feel silly for asking but the only stupid question is the one you don't ask.
It relates to the use of a 7L steel side slung cylinder.
I currently dive a single 15L and a 3 L pony which i have mounted across my lap.
With this combination i wear 6 Kg on my weight belt. The pony weighs 2.9Kg (empty)
Following a discussion with a CCR diver last October it was suggested a 7l side slung would be a better option than the 3L pony.
I could see the benefits of this approach.
I bought the 7L today it weighs 8Kg (empty). My questions are
1/ I assume i now ditch my weight belt altogether?
2/ Will my Dry suit and Northern Diver BCD provide me with enough lift?
3/ I assume in an emergency to gain positive bouyancy assuming an OOA you would dump the Side Slung?
4/ Is there any benefit in attaching a spare inflation hose to the side slung in the event of a primary cylinder failure?
5/ Would it be benefical to mount the Side Slung acoss the body to maintain U/W balance and trim or is it OK to the side?

Sorry if my questions seem dumb but it's all a bit new to me and these questions appeared in my mind so i thought i'd ask those who would know.
The purpose is at this time purely as a bail out gas on 30M-40M dives . I may progress to Deco Mixes/twin sets etc at a later date as my diving progresses.
Thanks in advance

[nigelH]

Originally Posted by Daz217

I bought the 7L today it weighs 8Kg (empty). My questions are
1/ I assume i now ditch my weight belt altogether?

No.

It displaces 7L plus of water so 7Kgs plus of upthrust.
Add some regs and some gas and it will probably be about 2Kg negative.

I have a 'Fisherman's scale' to weigh things with in my water butt. It helps with these questions. Most kit contributes very little to your weighting.

I dive a pair of 7L steel bailout stages and don't adjust my weight at all so I can hand them off if required and it doesn't really make much difference.

[Daz217]

Ok that makes sense although i hadn't thought of it in that way
So keep the 6Kg on?

[RichW]

Daz,

These questions can be difficult to answer over the interent, as a lt of this depends on whether you are corrctly weighted in the first place. What you need to do is to do a weight check, to ensure that you can hold a stop with little gas in your main cylinders.

You also need to be sure that your BC provides sufficient lift when you have a full cylinder and stage. Basically you need to make sure that the negatively buoyant equipment is balanced by the positiviely buoyant equipment.

Theres an excellent article here about balancing your equipment

http://www.wreckandcave.co.uk/2006/1...-does-it-mean/

Rich

[Daz217]

Thankyou for that. My weighting is spot on for fresh water managing a 3M stop comfortably on the 15L and 3 L Pony mind you that is with the 3 L full and the 15 L at between 100 and 50 Bar.
Just wondered what if any to deduct for the 7L.
Thanks for the link i' ve skimmed through it but will look at it in more detail later.
What about balance and trim with just the one side mount?

[Narked@50]

Hi Daz

Both the above are good answers, I would also add the best way to determine most of this would be a dip in your local quarry, then make a +2kg adjustment for salt water if you feel the need.

I can see why you have gone this way, but twims would have been more appropriate as your litteraly diving them now - just poorly configured as a 15 and a 7 .

The second hose is an option, but in a main cylinder failure you will be going up, not down, so releasing air. You could oraly inflate on the surface if you ever really had to, and you weighting would be minimal as you main cylinder would be empty in your scenario.

So a lot of this is going to be preferance - go have a play.

James

[Daz217]

Thanks, I hear what you say. However it started with a kiss....... erm sorry i meant to say i never intended to go any further than single tank diving. Then i got the pony then came the conversation with the nice CCR guy that got me thinking (Is a 3L pony enough to get me out the sticky brown stuff from 30M +?) hence taking the advice re the 7L.
I agree twins would be the answer but the simple truth is i could not afford them at the moment and i would also have to buy a new wing/BCD capable of taking twins not to mention needing bands/manifold etc. I can't afford that sort of money at the minute.
I am off to Stoney on Tuesday so i'll play then and see what works best. As i say i never intended taking this route but now i have the gear i'd best learn how to configure it and use it.

[Daz217]

The Cylinder Buoyancy thread helped 7L steel is negative 1.7Kg when full and 0.1Kg when empty so i'll keep the 6Kg on and see what happens.

[Mark Chase]

Originally Posted by Daz217

I feel silly for asking but the only stupid question is the one you don't ask.
It relates to the use of a 7L steel side slung cylinder.
I currently dive a single 15L and a 3 L pony which i have mounted across my lap.
With this combination i wear 6 Kg on my weight belt. The pony weighs 2.9Kg (empty)
Following a discussion with a CCR diver last October it was suggested a 7l side slung would be a better option than the 3L pony.
I could see the benefits of this approach.
I bought the 7L today it weighs 8Kg (empty). My questions are
1/ I assume i now ditch my weight belt altogether?
2/ Will my Dry suit and Northern Diver BCD provide me with enough lift?
3/ I assume in an emergency to gain positive bouyancy assuming an OOA you would dump the Side Slung?
4/ Is there any benefit in attaching a spare inflation hose to the side slung in the event of a primary cylinder failure?
5/ Would it be benefical to mount the Side Slung acoss the body to maintain U/W balance and trim or is it OK to the side?

Sorry if my questions seem dumb but it's all a bit new to me and these questions appeared in my mind so i thought i'd ask those who would know.
The purpose is at this time purely as a bail out gas on 30M-40M dives . I may progress to Deco Mixes/twin sets etc at a later date as my diving progresses.
Thanks in advance

A Faber Lightweight 7ltr steel tank is neutrol or slightly positive empty and floats arse up with 100 bar in. and its totaly irelevent to your weighting.

Sort your weighting out without the stage then add the stage. Even with full 235bar of gas it will only be 1kg neg in the water so if its riged properly it will be insignificant to your diving position trim etc just cross balance it with other equipmnet.

I dived for years with suit inflation runing off of a deco stage. Now days its preferable to have a seporate suit inflation bottle. (its a fashon thing) Personaly i would keep a hose on the deco tin fo the day when my suit inflation bottle is empty or fails in some other way. Its no hassle to have the extra hose and it can double as SMB inflation or lift bag inflation if you pit a gun or dog dick inflator on the end.

Cross belly mounting of tanks dosent work that well ( all the weight of a tank it at the top any way) so stick to side slung.

I strugle to think of a situation where you would ditch the stage? If you need to ditch something to stay on the surface ditching somthing as light as a stage is unlikley to help. Stick to ditching your lead. Much cheeper any way.

ATB

Mark Chase

[Mark Chase]

Originally Posted by Daz217

The Cylinder Buoyancy thread helped 7L steel is negative 1.7Kg when full and 0.1Kg when empty so i'll keep the 6Kg on and see what happens.

Neg 1kg whn empty??? This one has 100 bar in



Can you read the gague



Dont beleive the hype.