What size stages

A

antsdd

New Member
Hi
Just a question I dive a inspiration classic currently trained to 60 mtrs
I am planning my advanced mixed gas later in the year
My dilemma is I currently dive with either 2 x7ltr stages or a 11bailout and 7 deco
I was thinking of going to two 11s but I get earache of the wife with my collection of cylinders
Do I sell the 7s and stick with 11s all the time or keep the 7s too
Cheers anthony
 
Lol - "earache of the wife". I just read that to my wife. I found it funnier...


John H Hanzl
Author, Out of Hell's Kitchen
 
I would like to know what she considers a "collection of cylinders." I have nearly 40. Maybe telling her that will reduce the earache.

BTW, John, I like the new avatar.
 
For dives of up to two hours I use two 7s and a drop tank

Dives over two hours I use two large tanks (10ltr steel and 11 ltr Ali) + a drop tank


I could use the big tanks for everything but doing a 40m dive for two hours with large tanks seems a bit over kill and besides which my gas needs are diferent as a 3 hour dive is usualy deeper so diferent bailout gas required.

For my sort of diving I need at least a 10ltr frop tank two large tanks for deco and bailout and two small tanks for deco and bailout and I keep a further large tank for three gas very deep dives.

so

2 X Al80 (Nitrox 50 in one and 10/70 in the other)
2 X Steel 10 (Trimix 14/65 and Nitrox 80% drop tank)
2 X Steel 7 (Trimix 18/45 Nitrox 50%)

ATB

Mark



ATB

Mark.
 
My diving 'styles' are quite varied so my bail-out needs to meet numerous scenarios.

The gas in my 3 litre diluent cylinders is usually 20/30 and does not figure in any contingency plans. However I generally mount steel 7s with either 15/45 or 10/60. With oc access, via BOV or second stage this reserve of gas can be included in bail-out contingency.

I can also access all my off-board gas via BOV or second stages and they comprise:

Aluminium 7s - 80%, 50%, 32% & 20/20
Aluminium 11s - 50%, 18/45 & 15/55
Steel 10 drop cylinder - 80%

Including my oc cylinders, most of which are now being used to bank ccr gas, I have around 30 and can, of course, easily justify more. Welcome to the madness...

HTH, Tim
 
Looks like she will have to clamber over then in the porch then
Two 11s for deeper and 7s shallower
Just was wondering what most dive with
I have seen people doing a 80mtr plus dive with 2 7s for bailout and no drop bottle, and I heard of a guy with no bailout going to 75 mtrs
My life is more valuable than that
I am pretty new to the 55mtrs plus and want to dive as safe as I can
Cheers
Anthony
 
Never sell a cylinder - the day you do, you'll need a new one.

Consider this: the space vacated in your bed by an ex wife will typically accommodate four al80s and probably a couple of al40s as well. Cylinders are typically a hell of a lot cheaper to maintain, too.
 
Randy Thornton said:
Mostly dive with aluminum 80s or 72s. I don't care for the extra weight of steels when diving CCR.
Click to expand...

I don't have a lot of experience with larger side mounted steels but was looking at lp50's and surprised to find out there is little in the way of size and weight out of the water and only a pound or two difference in the water than aluminum 40's.

LP 85's don't seem that much heavier than aluminum 80's either just by looking at the stats. I plan on trying before buying so not so sure I will like steel over aluminum, just toying with the idea of having the ability to pump more gas if necessary.
 
Captain Starfish said:
Never sell a cylinder - the day you do, you'll need a new one.

Consider this: the space vacated in your bed by an ex wife will typically accommodate four al80s and probably a couple of al40s as well. Cylinders are typically a hell of a lot cheaper to maintain, too.
Click to expand...


I second never sell a cylinder, you will always find a use.
presently maintain for cave
2 lp's 85 30/30 mix
2 hp 100 18/45 mix
1 al80 21/35 mix
1 al80 18/40 mix
1 al40 50/10 mix
1 al40 100 O2

When wreck diving the al tanks are my bail with the then app mix for the dives
they are used as stage cylinders when caving.

I also have a few other steels which I use as storage for top offs.

I guess your earaches are going to get worse, unless you develop
the life survival selective hearing.
Gabe
 
Randy Thornton said:
Mostly dive with aluminum 80s or 72s. I don't care for the extra weight of steels when diving CCR.
Click to expand...

In europe we have light weight steels which are great for trimix as they float arse up full and are neutrol empty


Note steel with 250 bar trimix in floating arse up in fresh water

Al 80 with 235 bar 50% in is neg on the bottom

HPIM0017.jpg



7ltr steel on left has 50 bar nitrox in, steel on the right has 250 bar nitrox in.

seetheyfloat3.jpg
 
Last edited:
I put in a bit of he in my 50% and then its more nutral, in my alu 80s.
Often around 15-20% he that is.
Have around 220bars in my bottels

Tomas
 
I hope everyone keeps in mind that choosing bailout cylinders should also include a plan for using them. If you have to bail out, you will be using the gas and therefore become more buoyant. With aluminum bailouts, some choose to remove empties and let them float up the line (assuming no overhead), but with steels this would make you even more buoyant. There is no one right answer for all situations. Just suggesting that you take the complete bailout picture into your plan when deciding about the cylinders and weighting.
 
kwinter said:
I hope everyone keeps in mind that choosing bailout cylinders should also include a plan for using them. If you have to bail out, you will be using the gas and therefore become more buoyant. With aluminum bailouts, some choose to remove empties and let them float up the line (assuming no overhead), but with steels this would make you even more buoyant. There is no one right answer for all situations. Just suggesting that you take the complete bailout picture into your plan when deciding about the cylinders and weighting.
Click to expand...

Well said Ken!
 
Are these specs right? taken from (DGE)

Aluminum 80 Luxfer 3000PSI 7.25"dia 26.1height 31.4weight out of water - 1.4 full : + 3.4 empty
LP-85 (Faber 13) 2640PSI 7.01"dia 25.9height 31.2weight out of water -3.80 full : + 2.32 empty

Aluminum 40 Luxfer 3000PSI 5.25"dia 24.6height 15.3weight out of water - 0.7 full : + 1.8 empty
LP-50 (Faber 7.8L) 2640PSI 5.51"dia 25.2height 18.9weight out of water -2.43 full : + 1.24 empty
 
If these figures are right (without the valves) it would seem as though there is little difference from LP 85's and luxfer Al 80's. Not saying its right or wrong to "cave fill" I do know of people who boost their 85's to 3400-3500psi which would give them 112 cuft of gas in each cylinder.
 
kwinter said:
I hope everyone keeps in mind that choosing bailout cylinders should also include a plan for using them. If you have to bail out, you will be using the gas and therefore become more buoyant. With aluminum bailouts, some choose to remove empties and let them float up the line (assuming no overhead), but with steels this would make you even more buoyant. There is no one right answer for all situations. Just suggesting that you take the complete bailout picture into your plan when deciding about the cylinders and weighting.
Click to expand...

when people float up their 80's up the line does that mean they are using all the gas in their cylinders? if they aren't and letting them float up the line what is the procedure for gathering them up at the end of the dive? Does the mate do this?

Thanks,
Garth
 
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