Question Different tanks for SM and CC bailout?

[mr_v]

Howdy,

I am in the market for new tanks and wondering if ya'll have different setups for SM and bailout. Logic - some tanks will be great for SM but too heavy for bailout and vice versa. Note, the question is about the bottles you'd carry, not stages/safeties.

Looking for deep bailout mixes, so 15/55 - 10/70. I am inclined going with steel galvanized tanks like LP85s (either Faber or Worthy) or PST 104s.

Several assumptions:

- My CCR is properly weighted - if I ditch all bottles I will probably be neutral or slightly negative, depending on accessories
- I won't ditch the tanks when they get close to empty
- Dives requiring these bottles will be with a DPV

However, I am open to other opinions. Thank you!

 

[Fat old english bloke]

Not from a weight/mass perspective, only in terms of gas, though most of my dives are shallow, so I have four pairs of tins that I’d use for both, and one pair, some Faber 15s, that I’d only really have need for on a CCR.

Have been toying with the idea of getting a twinset for BO in larger, deeper, spaces.

Edit: all tanks are 232bar Faber or Vitkovice steel and vary from 5 to 15 litres.

 

[Dsix36]

I use 2 AL80's for both OC sidemount and bailout for my rebreather. They are rigged differently due to different harnesses and needing to move the OC tanks down when they get light.

 

[LFMarm]

If I could choose, I would use Al80s for everything because I do not need much lead even when diving dry and Al80s are really nice to handle in and out of the water.

However I am diving a set of HP100s / steel 12L as sidemount tanks with bottom and travel gas and 2 AL80s with 50% and 100%. Only advantage of this setup for me is 40cf of more deep gas at the expense of a non balanced rig.

 

[rjack321]

In a cave? or in open water?

LP85s up through hp130s actually ride pretty nice with 35-70% helium in them but the tails are going to ride up. Diving two of them SM in a cave with a backmounted CCR is legit.

In open water I carry an AL80 and then start adding deeper and deeper deco gases to handle the reduced/minimal volume of bottom BO. 12/65 plus 21/35 for instance.

 

[mr_v]

I guess my quest for a single tank to rule them all won't happen.

For dives up to 120' or so, I am using my AL72s as bailout bottles. Love that bottle for everything - size, buoyancy, the way it rides and handles while passing it to another diver. Unfortunately, for deeper dives AL72 yields ~64cf of actual lean trimix volume - not ideal.

I finally gave in and purchased two LP85s Worthys. I'll test them SM with 32, but eventually they'll get cave 15/55 or 12/65 fills. Can't wait to see the bill for those fills. Thought about 95s and 104s but decided against due to drag and maneuverability. And of course, these Worthys won't be the only deep bailout options.

 

[rjack321]

I guess my quest for a single tank to rule them all won't happen.

For dives up to 120' or so, I am using my AL72s as bailout bottles. Love that bottle for everything - size, buoyancy, the way it rides and handles while passing it to another diver. Unfortunately, for deeper dives AL72 yields ~64cf of actual lean trimix volume - not ideal.

I finally gave in and purchased two LP85s Worthys. I'll test them SM with 32, but eventually they'll get cave 15/55 or 12/65 fills. Can't wait to see the bill for those fills. Thought about 95s and 104s but decided against due to drag and maneuverability. And of course, these Worthys won't be the only deep bailout options.

Honestly for me lp85s with 32 feel like bricks to me when combined with the already heavy-ish Meg. I've done that in FL a bunch of times though. They are comfy with mix in them. I suspect you'll like them once you move to mix in them. Even 130s are nice with 18/45

 

[mr_v]

Honestly for me lp85s with 32 feel like bricks to me when combined with the already heavy-ish Meg. I've done that in FL a bunch of times though. They are comfy with mix in them. I suspect you'll like them once you move to mix in them. Even 130s are nice with 18/45

Sounds like we have the same setup. It will be Meg + 2 LP82s cave filled with some mix and a few stage bottles.

 

[rjack321]

Sounds like we have the same setup. It will be Meg + 2 LP82s cave filled with some mix and a few stage bottles.

For big backmount cave, I like the Meg with 2x SM steels. Those kinds of cave dives are kinda rare for me lately.

In the ocean/great lakes I dont really dive deeper than 240ft-ish often which is the margins of the fun zone. So it's rare that I add a deco gas deeper than a 70ft bottle. Probably 95% of my open water tech dives are 2x AL80s and occasionally an al30 or 40 underslung on the left side. If I am really pushing it depthwise I nose clip the 40 on my butt rails, and add a 21/35 intermediate stage underneath the deep BO on the left. So I end up with 12/65(L), 21/35(L), 50%(R), and 100%(butt)

 

[mr_v]

For big backmount cave, I like the Meg with 2x SM steels. Those kinds of cave dives are kinda rare for me lately.

We need to fix that problem! I am mostly concentrating on deep cave diving now, and will be more than happy to share the passion with a few very qualified buddies. Our Meg crew is going to Eagle's Nest at least once per month. It is a polished operation that has been several years in the making.

In the ocean/great lakes I dont really dive deeper than 240ft-ish often which is the margins of the fun zone. So it's rare that I add a deco gas deeper than a 70ft bottle. Probably 95% of my open water tech dives are 2x AL80s and occasionally an al30 or 40 underslung on the left side. If I am really pushing it depthwise I nose clip the 40 on my butt rails, and add a 21/35 intermediate stage underneath the deep BO on the left. So I end up with 12/65(L), 21/35(L), 50%(R), and 100%(butt)

Perhaps we can start a new discussion on butt clips, but I am curious why you'd clip a 100% to your butt. I tried that in OW and did not enjoy the tail.

Also, am I the only one who OCDs on valve / regulator placement? For 21/35, I need two bottles with mirrored valves, as sometimes 21/35 will sit on the left and sometimes it will sit on the right. I know, first world problems.