Doubling Up...

[prthd9]

Deepsea and NS have given you very good advice. I've been diving for almost two years with almost hundred dives in just the past year. I am just now starting to think about doubles.

To decrease your air consumption dive more, relax while at depth, if you surface swim to your dive spot take a break before descending, and go running to get in shape. You can also get a reg that does not require you to exert as much effort when breathing.

Doubles are not the answer....................Good luck to you and safe diving.

 

[Tom Winters]

Doubles are cool, but they are a PITA to dive with. If they're what you need though, go for it. Take good care of your back - in the winter, some of you Canadian guys get a little sedentary.

 

[jeckyll]

Doubles are cool, but they are a PITA to dive with. If they're what you need though, go for it. Take good care of your back - in the winter, some of you Canadian guys get a little sedentary.

Sketchy entries with slippery rocks and logs etc are great fun in doubles ... :no Though winter is the best time to dive on the West coast

To the OP: Don't worry about your air consumption yet.

• Go dive.
• Plan your dive.
• Find a good buddy who you enjoy diving with.
• Relax.
• Don't try to see the entire dive sight by motoring around at max speed.
• Make sure you are comfortable before descending and take a moment to compose at the bottom.

All of a sudden that AL80 may just last much longer

 

[Bobyjimmie]

My gas improvement kept increasing. Im actually diving with a smaller tank then my buddies and stay down as long if not longer then them still. There was no change in my fitness level. I run a couple miles every other day but Ive always done that. I started by staying down about 40 minutes in 45 feet of water (average depth and time) and now I average about 75 minutes in that depth. I think you will be wasting money on doubles for all the wrong reasons just learn to breath better and stop expelling so much energy underwater. Remember its not a race. Most people blow all their air through their BCD, so work on your buouyancy as well.

 

[SparticleBrane]

By thinking about doubles, you are trying to treat the symptom, but are not solving the root problem.

 

[Jimmer]

Doubles are cool, but they are a PITA to dive with. If they're what you need though, go for it. Take good care of your back - in the winter, some of you Canadian guys get a little sedentary.

That's why we have a little game called hockey.

 

[NSDiver]

ACR-

I've seen improvement in my gas consumption since OW, though I'd bet that most people would see more. I was already very comfortable in the water when I started - I'd attribute most of the improvement in SAC to getting better at basic diving skills (buoyancy, fin techniques, etc.).

When I first started I saw around 0.6-0.7, and now I usually get 0.4-0.5. I'd say that's some improvement.

If you find that you still can't get much on an AL80 after a few more dives, it probably wouldn't be a bad idea to look into a higher capacity tank, ideally a steel tank (I'd assume you are a cold water diver). I haven't dove doubles, but they seem to be a pretty big step, not only from a diving perspective but also from a financial perspective (new wing, a second first stage, bands, manifold...)

I hope you find something that works for you.

-Nick

 

[TSandM]

Most of the high gas consumption seen in new divers is due to a combination of a lack of ease in the water, and inefficient diving technique. The ease and relaxation will come with repeated dives, but the inefficiency needs to be addressed and fixed.

The sources of it are: 1) Overweighting. Formal weight checking is a good place to start. Many students are (deliberately or otherwise) overweighted for their OW dives. If they continue to use that weighting, they are coping with a very inefficient system. 2) Poor trim. If you are weighted such that you are diving at a 45 degree angle to the sea floor, you have to stay negative, because every kick drives you both forward and upwards. Much of your effort is wasted, but all effort uses gas. 3) Hurrying. Scuba is a sport for relaxed tourism, not for setting time or distance records.

Fix those things, and you'll see your gas consumption come down. Of course, if you are a large-framed adult male, you WILL use more gas than some other people, and you may eventually decide that you need a larger tank for more bottom time. HP 130s are lovely for this.

Doubles are a PITA. They're heavy and hard to move around. They require two regulators, and they don't help you if you don't know how to manage the valves and cope with failures. They can be very difficult to balance properly. They are merited when the depth of the dives warrants the redundancy that they offer.

 

[1_T_Submariner]

Good Thread and great answers. I dive a HP120 and even when filled to 3000psi (105 cu/ft) it still last a long time (90+ minutes on a shallow dive). You might want to check out a used Hp120 if you are under 5'10" it might be little on the tall side.

 

[Jimmer]

ACR, well my offer is obviously still on the table to let you try out both of my sets if you like (Lp108's and 72's). The Lp 108's might make you go running from the idea of doubles forever haha. But other than just trying the doubles, I'll be more than happy to give you whatever advice I can as far as proper weighting, buoyancy etc.

Another thought popped into my head today, I assume you don't own tanks yet. In which case why not consider buying a pair of al80's as singles for now, then when you feel you're ready, or if you find yourself doing a lot of deep dives, which incidentally is my reason for initially wanting doubles for redundancy on deeper dives, then you can double them up. 80's are awesome doubles to learn on, and the best part is that even if you get heavy into tech and swap up to 108/119/130 etc, the 80's still work wonders as stage bottles.