Back mount O2ptima, Access to onboard 02

[Zebra 1]

We have stock BMCL O2ptima's with a QC for our bailout which we are changing out to QC6's.

Our BOV's are plumbed into our onboard cave filled lp27's (35cuft) and an al40 (when the QC is plugged in to the manifold).

What would be good plumbing options to be able to access the 20-30cuft of 02 on our back (@20') in BO?

 

[rjack321]

Onboard CCR tanks are not OC BO, period, end of story. Don't plug your BOV into onboard tanks and don't rely on onboard O2 as an OC deco gas either.

 

[tbone1004]

@Zebra 1 I strongly recommend you listen to what @rjack321 said. I would change that onboard "dil" bottle into a suit and wing inflator, and go to offboard only for your ADV/BOV. Leave the O2 as is and don't try to put a second stage on it. If you need O2 for deco, then you need to bring an O2 bottle.

 

[Zebra 1]

Thank you,
I'm not going to rely on it and it's never a part of my gas plan.
We dive wet so it's either carry gas or lead, as the saying goes I'd rather carry gas than lead.
Seems prudent to have access to said gas.

 

[Whitrzac]

The o2 tank is rarely 100% full.
I don't think I've met anyone actually using lp27s, I know a few that have them for when they go on liveabord trips and need to dive an entire week without filling tanks

 

[rjack321]

Thank you,
I'm not going to rely on it and it's never a part of my gas plan.
We dive wet so it's either carry gas or lead, as the saying goes I'd rather carry gas than lead.
Seems prudent to have access to said gas.

Putting an OC reg on your CCR bottles is just creating another way to lose that gas (the lp hose and 2nd stages). Plus now you potentially have a real OC BO 2nd, a deco gas, plus 2 more 2nd stages on your CCR tanks. What a confusing mess in a stressful situation.

Its not enough volume to do anything useful on OC, just leave the 2nd stages off

 

[rjack321]

The o2 tank is rarely 100% full.
I don't think I've met anyone actually using lp27s, I know a few that have them for when they go on liveabord trips and need to dive an entire week without filling tanks

They are fat and annoyingly bulky

 

[Tracy]

The o2 tank is rarely 100% full.
I don't think I've met anyone actually using lp27s, I know a few that have them for when they go on liveabord trips and need to dive an entire week without filling tanks

Optima tank of choice in the great white north. Either gas or lead, gas makes more sense. I love them. Easily do a weekend of tech diving without the slightest concern for fills.

 

[Zebra 1]

lp27's are very popular with O2ptima divers when diving wet, again we need the weight.

On a 100ft dive for 50 min my BO on 32 is 89min using 32cuft. Adding O2 is 68min with using a total of 16cuft (8cuft of 32 and 8cuft of oxygen).

I carry a transfill whip and keep our bottles topped up.

We dive rigs in the gulf and normally stage 02 at 20ft, either on the downline of tied off to the rig.

I was thinking of adding a QC6 and hose to my oxygen manifold (clearly marked and following gas switching protocols).

I know many here are opposed to the BOV being plumbed to backgas.
I really don't want this to turn into that debate which I think has been well covered in previous threads.

 

[grantctobin]

lp27's are very popular with O2ptima divers when diving wet, again we need the weight.

On a 100ft dive for 50 min my BO on 32 is 89min using 32cuft. Adding O2 is 68min with using a total of 16cuft (8cuft of 32 and 8cuft of oxygen).

I carry a transfill whip and keep our bottles topped up.

We dive rigs in the gulf and normally stage 02 at 20ft, either on the downline of tied off to the rig.

I was thinking of adding a QC6 and hose to my oxygen manifold (clearly marked and following gas switching protocols).

I know many here are opposed to the BOV being plumbed to backgas.
I really don't want this to turn into that debate which I think has been well covered in previous threads.

Given your other threads and desire to attempt this, I have to ask. Are you planning to spearfish with the onboard LP27s as your primary “bailout”?