OMS wings vs Apeks wings and LP vs HP tanks

[PerroneFord]

The short story is that for most LP tanks there is a similar sized HP tank that will hold vuirtually trhe same volume in a package the same weight and size.

So the 2400 psi LP 95 makes sense in North Florida where you can get a 3600 psi cave fill, but the HP 130 makes much more sense over all as it can legally be filled to 3442 psi anywhere.

While this is true, the buoyancy and balance characteristics are not the same. And this is why you still see some of us using LP tanks. Double 130s are also heavier (with the same fill) than double 95s. That makes a difference for some as well.

 

[Scuba-Stu]

While this is true, the buoyancy and balance characteristics are not the same. And this is why you still see some of us using LP tanks. Double 130s are also heavier (with the same fill) than double 95s. That makes a difference for some as well.

Apples to oranges?

I thought 130s were equivalent to 108s and 119s were equivalent to 95s?

 

[rjack321]

Do a serach in the tank section - the LP versus HP debate has been covered ad nauseum. The short story is that for most LP tanks there is a similar sized HP tank that will hold vuirtually trhe same volume in a package the same weight and size. For example an LP 95 and an HP 130 are similar in size and weight and both hold about 130 cu ft at 3500-3600 psi. So the 2400 psi LP 95 makes sense in North Florida where you can get a 3600 psi cave fill, but the HP 130 makes much more sense over all as it can legally be filled to 3442 psi anywhere.

Their bouyancy is quite different. HP tanks being 2 to 4 lbs more negative than LP tanks. Which can be nice (sometimes even important) depending on water type and the exposure protection you're trying to sink.

If I were in cold New England salt water I would get HP tanks. In warmer Florida fresh water, LP tanks.

 

[PerroneFord]

Apples to oranges?

I thought 130s were equivalent to 108s and 119s were equivalent to 95s?

Yes, correct. But my comments still hold. I remember swapping 108s with a friends 130s and being surprised by the differences.

 

[Scuba-Stu]

Yes, correct. But my comments still hold. I remember swapping 108s with a friends 130s and being surprised by the differences.

Sorry I wasn't really directing that at you, I was just confused.

 

[PerroneFord]

Sorry I wasn't really directing that at you, I was just confused.

LOL, no problem. Shoe fit, so I slipped it on...

 

[Colliam7]

You raise two good questions (wing size, and need for a redundant bladder), admittedly discussed in several threads before, but it is helpful to periodically renew thinking and discussion.

I have looked at the OMS 100 lb. lift double bladder BC with the rubber bands around it and have also looked at the Apeks WTX6R "Buoyancy Cell". Which one would you choose and WHY?

I've personally carried 5 tanks, and have seen divers with 8 tanks, and I have never needed more than 40 pounds of lift, and have never worn a wing bigger than a 60. And that is nearly always too much.

Very good advice. I started with a 77 lb DR Super Wing (which also has a dual bladder), thinking I would want more lift with a set of double HP120s. It was far more than I needed. I now use a 50 lb (Oxycheq Signature) or 55 lb (Halcyon Explorer) wing - both single bladder -with multiple deco bottles, and either wing offers plenty of lift - as much as (or more than) I need. A 100 lb wing seems needlessly massive (unless you are doing S&R - perhaps bringing up automobiles, or drowned sumo wrestlers).

Do you need double bladder, It seems like a little more redundancy and safer to me, but I don't know?

In practice, you want redundant bouyancy when diving heavier doubles, with additional bottles, etc.

Double bladders seem like a good idea on paper, but honestly, in the water not so much.

Again, sage advice. There are many sources of redundancy (drysuit, lift bag/SMB, or even two single wings mounted back to back as DA mentioned) and a dual bladder isn't necessary. Having said that, I still have my dual bladder Super Wing (albeit it is very infrequently used), and recently bought a Nomad sidemount set-up with dual bladder, since I plan to dive SM wet most of the time. Essential? Not at all. OK to have? Yes.

I've pretty much settled on getting the XTX200 regs, but I'm open to suggestion.

Excellent regulators. I have ATX 200s and love them. Many other good regulators out there. But, you would not be disappointed with the XTX 200s.

I've heard that the LP's are easier on the regulators, any truth to this?

It is regularly suggested but seems to be, at best, an anecdotal concern. I dive HP120s (3500psi) and have never noticed any problems with my regulators (Apeks or Zeagle ZX-50Ds), nor do I notice any particularly greater wear and tear when I service them.

 

[mutiny360]

I dive an apeks 45 pound wing with double steel HP 100s. Works great. I carry a lift bag for backup lift if the wing would fail. I would stay away from banded wings they snag and trap air, the tech instructor at the local shop won't allow students to use them. I dive apeks xtx 50 regs, love them, no problems, similar to 200s.

 

[RonFrank]

I have dove doubles on many an occasion. Since I don't own these tanks, I use my buddies bladder which has 45lbs of lift. These are double Al80, so positive when empty, but they are never empty. You need maybe 10lbs to offset the tanks. Regulator fists stages are a few lbs, so take that into consideration.

I can not see ever needing a 100lbs wing. With the 45lbs wing I barely had any air in it at all diving to 85' with fulll doubles. From my single tank experience that is normal as I don't need much air in my bladder in that situation either. I dive in a drysuit so that is my backup. However I do not use the suit for buoyancy.

If you dive steel tanks, than they are generally negative when empty, so no extra weighting is necessary. LP/HP is debatable, but I like HP even if I rarely dive them. You can always fill a HP tank to 3000psi and I know a lot of shops that don't know what a LP tank is, so that get's filled to 3000psi as well. Overfilling IMO is worst than under filling. Since these are hydro'd at 5000psi, any tank on the market can take overfilling, but IMO not the best approach.

Tank size should be based on the depth or dive plan. 130's are heavy tanks times two, and maybe more gas than necessary, but that depends on what you are doing. Keep in mind that stage gas maybe a different mix, so having a lot of air in your doubles that you are not breathing does little other than add more safety margin.

 

[PerroneFord]

Keep in mind that stage gas maybe a different mix, so having a lot of air in your doubles that you are not breathing does little other than add more safety margin.

Stage gas, by definition, implies the same mix as backgas.