Doubles VS HP 130

[rhwestfall]

I scanned this quickly, so if this is a repeat, I beg forgiveness.... Many opt for the doubles (and configured as LP) as a HP fill can, at times, be difficult to obtain.

I am currently in the "big single tank" category as I usually dive HP120's or an AL100 for dives in the 100'-130' range). Using these tanks, I am at the NDL limits as well as managing proper gas reserves for this diving. In the near future (actually this Thursday), I will be in an "Intro-to-Tech" class and getting exposure to doubles. I have a recently acquired pair of HP100's that are in contention to be twinned should I like the experience.

 

[iluvtheocean]

the only problem i have with my pst HP130s is since they are so heavy out of the water i find that using a weight belt instead of the integrated pockets on my BC make it easier to put on for shore dives

 

[Dr. Lecter]

Do both: I love my double 130s

My back, however, is not as much of a fan.

 

[James R]

Find lighter tanks, or get a stronger back is all you can do haha

 

[Instructor_Tom]

You're right! I re-checked my notes for diving LP85s, and I had forgotten that I used to put a 3lb tail weight on the bottom bolt when they were doubled and 4lbs on a belt when using them in sidemount, my mistake on that. It's been a year since I dove them in doubles or sidemount! As singles I can dive them with AL plate, 5mm suit & hooded vest with no additional weights, but I sink like a rock (ie no weight needed to dive AL80 with a 3mm suit in salt water). Also, my 5mm suit has over 500 dives on it (yes It is sacked and needs to be replaced) so it's compressed about as much as it can be I think. It may be more like a 3.5 or 4mm at this point.

So yeah, I should have checked my notes before posting yesterday. My mistake. Sorry about that.

James;

Thanks for the vindication, those 3-4lb trim weights make a huge difference. When diving overhead environment in back mounted config; tank mounted anything is a big no-no.


Sent from my iPad using Tapatalk HD

 

[Dr. Lecter]

Find lighter tanks, or get a stronger back is all you can do haha

Third option: buy a CCR.

 

[James R]

James;
Thanks for the vindication, those 3-4lb trim weights make a huge difference. When diving overhead environment in back mounted config; tank mounted anything is a big no-no.

I can admit when I've made a mistake, no worries!

I am not sure I see any inherent issue with a tail weight hanging on the lower bolt of back-mounted doubles. It's wedged between my backplate and the tanks, and it would be pretty much impossible for it to come loose or be an entanglement hazard.

 

[nimoh]

Do both: I love my double 130s

My back, however, is not as much of a fan.

me too, although when my back can't handle them, I will move them to my sides

 

[Instructor_Tom]

I can admit when I've made a mistake, no worries!

I am not sure I see any inherent issue with a tail weight hanging on the lower bolt of back-mounted doubles. It's wedged between my backplate and the tanks, and it would be pretty much impossible for it to come loose or be an entanglement hazard.

When i actually started diving doubles i had a tail weight on my backplate. But it was more of a crutch for not having the tank properly balanced. Over time i was able to drop all weights from my configuration even when diving dry and now have my doubles rig down to a nice trim 150lbs; yeah.....


Sent from my iPad using Tapatalk HD

 

[Colliam7]

Part of me is saying buy an HP 130 and save the wings and dual tank set up. Another part of me says, sooner or later every recreational diver will get into tech and then the 130 may not see as much use. Id love to hear from folks who go doubles instead of gigantic single tanks or vice versa.

My largest single cylinders are 120s, although I have used borrowed HP130s many times for recreational dives. I dive doubles, a lot, for recreational diving. My favorite doubles set, based on buoyancy and trim characteristics, is a pair of AL80s. My subjective perception is that I feel a bit more roll with a single HP130 than I do with double AL80s. But, that is just me and it could well just be my imagination.

I started with doubles as part of tech training, so I acquired the initial set of doubles regs, the wing, etc., for a purpose other than adding a bit more bottom time to my recreational dives. So, when I started using double cylinders for recreational dives, I did not have to make a significant investment in new equipment.

Doubles vs a large single cylinder for recreational dives? The answer is very much like the answer to which BCD, which regulator, etc. It is largely a matter of individual preference. I personally think HP149s are huge and unwieldy, but dumpsterdiver likes them. Both of us are right, for us. I do like the redundancy of double cylinders, but I also like the redundancy of diving a single back cylinder with a smaller pony bottle.

Personally, I think I benefited from the training in which I learned to use doubles. I think it expanded my horizons as a diver. Therefore, I could possibly argue that doubles might be a worthwhile choice, because of the training you would presumably / should take to develop proficiency in their use. But, that may not be of value to you.