DiveRite Optima CM upgrades

[addohm]

If you can afford a rebreather, you can afford a transfill whip.

I use a transfill whip to balance my SM LP50s and then top them off with my hp100s. You’d be shocked how long that works.

Im not talking about balancing the cylinders before a dive. I'm talking about having balanced cylinders throughout a dive. I think @inquis suggestion makes the most sense and doesn't add parts\complexity to my current kit.

 

[inquis]

I think @inquis suggestion makes the most sense and doesn't add parts\complexity to my current kit

It also costs you more as you use richer helium mixes, so it's not without trade-offs.

 

[addohm]

It also costs you more as you use richer helium mixes, so it's not without trade-offs.

Fortunately for me I rarely have to use trimix or heliox gasses, so for now I'll be happy to try this

 

[AeroSpartacus]

Im not talking about balancing the cylinders before a dive. I'm talking about having balanced cylinders throughout a dive. I think @inquis suggestion makes the most sense and doesn't add parts\complexity to my current kit.

I have a QC6 male on both of my tanks. It's mostly for a contingency if for some reason I had loss of gas on the left bottle I could hook up the right one. But it generally just lives under the tank bands. I have, however, swapped diluent sides between dives before if the first dive ended with enough pressure difference and I didn't feel like getting my transfill whip or whatever (or maybe just had an in-water surface interval). Since it's QC6, you could do the same underwater but I haven't been off-weight enough to feel the need before.

 

[lostsheep]

For sidemount, assuming the same diluent and off board bailout, would it make sense to have a QC6-splitter so that you can use balanced amounts of diluent from both sides?

Not that this answers my question, frequently (2 days/week) 2.5+hr dives. Long enough to feel the unbalanced cylinders and also long enough that moving the clamp position isn't enough.

Perhaps that would be the case for me many hours down the road but it's not the case now. Also, for whatever it's worth, my dive profiles are usually very complex and there's a lot of changes in depth. I'm not concerned about the volume I use, I've managed that through planning. I'm asking purely for sidemount tank balance. I don't ever need to use my right cylinder except for emergencies.

Im not talking about balancing the cylinders before a dive. I'm talking about having balanced cylinders throughout a dive. I think @inquis suggestion makes the most sense and doesn't add parts\complexity to my current kit.

You shouldn’t be using enough dil on a 2.5 hour dive to be having problems with balance.

Sounds like something else is awry

 

[addohm]

You shouldn’t be using enough dil on a 2.5 hour dive to be having problems with balance.

Sounds like something else is awry

Yes you're right, I am a **** CCR diver!

 

[Capt Jim Wyatt]

For sidemount, assuming the same diluent and off board bailout, would it make sense to have a QC6-splitter so that you can use balanced amounts of diluent from both sides?

A solution to a non-existent problem. As @Tracy suggested a trans Fill at the surface should suffice.

 

[addohm]

A solution to a non-existent problem. As @Tracy suggested a trans Fill at the surface should suffice.

Again, I was speaking to while diving, not in between dives.

 

[Tracy]

Again, I was speaking to while diving, not in between dives.

Yeah, we get that. We are all just confused as to why. Sawtooth profiles aren't uncommon in cave diving. Something is amiss if you are using enough diluent on a single dive to warrant this.
You can shrug it off saying everybody else is an idiot if you like, but it doesn't change facts. You are doing something differently and it might be worth hopping in the water with somebody else to see where the gas is going.
In addition, even if you decide everybody else is wrong and you build your adapter. It won't work. You can't equalize tanks from the low side of the regulator. It won't draw evenly from them unless your IP is exactly the same on both regs. The odds of that are basically nil. It will primarily draw from the regulator with the highest IP.

 

[Capt Jim Wyatt]

Again, I was speaking to while diving, not in between dives.

I understood what you meant. You want to draw diluent off of two separate tanks while on the dive. While in "Theory" it sounds fine. In practice it is not needed, and creates failure points for no real value. If it is needed, then you are definitely doing something wrong.

MY last Choptima dive was for 159 minutes at 90 ffw. According to the Shearwater NERD2 download I used 352 psi out of a LP 85. That is a bit less than 23 FT3.

How much are you using?