Economical doubles?

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Rob, yes I am intrigued by sidemounts but want to make sure it is right for the diving I want to do.

You don't have to go into small passages to sidemount. Many cave divers sidemount and never go into passages not large enough to drive a car through. Many sidemount due to back and knee problems. Many sidemount just because that configuration trims out better. There are lots of reasons to dive sidemount.
 
You don't have to go into small passages to sidemount. Many cave divers sidemount and never go into passages not large enough to drive a car through. Many sidemount due to back and knee problems. Many sidemount just because that configuration trims out better. There are lots of reasons to dive sidemount.

Agree.

Sidemount has been around a long time on the other side of the ocean even for non-cave stuff. If I was starting out cave diving I would really consider sidemount. It provides even more redundancy (YMMV) than doubles and it's a very streamlined system. With my rebreather I carry my bailout bottles in the sidemount configuration (in my avatar I have two AL80s, can you see them under my arms?).
 
I waited two years and after experiencing the training and caves I am still in awe. Just beware the allure it will stick with you!
CamG Keep diving....keep training....keep learning!

I waited a little longer than two years, My OW check out dive was actually in Ginnie in Dec 1977. I have always been interested in the cave environment but due to years of mostly midwest quarry diving with a few tropical trips tossed in here and there just never had the oportunity to pursue. Fast forward thirty years: My youngest bro and I have been making a habit of getting to cave country as often as we can, (twice this winter already). Now I think I can justify the additional training and expense of going "cave". I guess from my posts it may sound like I'm new to this and from a certain point of view I am. I just want to be able to upgrade to the cave environment with minimal hassle as in: If doubles are the equipment that I will eventually need then I want to start getting used to doubles as quickly as possible so it is second nature when I finally start my training rather than taking it in all at once. I don't want to risk missing the important cave and safety stuff while trying to concentrate on learning a new gas configuration.

Thanx again and keep it coming.
 
Bug, I agree with the philosophy that you mentioned earlier about gas matching with your dive buddies. With my usual crowd I am the most efficient with my gas usage, I'm not saying I can hang with you guys but I do okay.

i'm not sure we're on the same page with you when we mention 'gas matching', so let me go over it a bit more. if you *were* understanding what we're talking about, please forgive me for explaining something you know.

if you're diving double 80s and i'm diving double 95s, i can still only use the same cubic feet of gas you do. your third is about 53cuft, and so instead of using the 87 or so cuft i'd be able to use with a buddy with 95s, i have to calculate and use only 53cuft, too. some people won't mind, but some will choose not to dive with you. and maybe you say good riddance to them :wink: but i wanted to explain that better. your sac rate has nothing to do with this, just the amount of gas in your tanks.
 
So you fall in that 10% of the population? Great! But you and I know 90% of FL cave divers and cave dives are done diving at JB, Hole, Twin, Madison, Peacock, Little River, Ginnie, Manatee, Telford, Cow, Hart, School Sink, Eagles Nest, Dipolar, etc. These caves suit HP130/LP104's very well.

I'm not real sure where you picked up on me implying running gas reserves to a max?

You can get decent dives in Twin, Peacock, and Telford with smaller tanks. There's alot you can do at Madison too since its not terribly deep and typically not flowing an aweful lot either. Depends on the dive.

My comment on gas reserves wasn't meant at you, I tried to push it down a few lines to seperate it from my response to you - I failed I guess.
 
i'm not sure we're on the same page with you when we mention 'gas matching', so let me go over it a bit more. if you *were* understanding what we're talking about, please forgive me for explaining something you know.

if you're diving double 80s and i'm diving double 95s, i can still only use the same cubic feet of gas you do. your third is about 53cuft, and so instead of using the 87 or so cuft i'd be able to use with a buddy with 95s, i have to calculate and use only 53cuft, too. some people won't mind, but some will choose not to dive with you. and maybe you say good riddance to them :wink: but i wanted to explain that better. your sac rate has nothing to do with this, just the amount of gas in your tanks.

To expand on this, with a 95 (3600 psi fill) using a 6th you would have 43~cuft (600 psi) of gas, with an 80 (3000 psi fill) using a 6th I believe it's 24~ cu ft (500 psi) of gas, so instead of using the 600 psi I would normally use with a 95, I would have to match your gas and reduce the volume I could use down to 24~ cu ft (350 psi)

Ultimately the gas available in PSI to use for each diver would be 350psi for the diver with 95's, and 500 psi for the diver with 80's

As to why gas matching is important, If the diver with 95's loses all his gas and both divers are diving straight 6ths, then the diver diving 80's will not have enough gas to get the other diver out.
 
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You don't have to go into small passages to sidemount. Many cave divers sidemount and never go into passages not large enough to drive a car through. Many sidemount due to back and knee problems. Many sidemount just because that configuration trims out better. There are lots of reasons to dive sidemount.

Very true. My partner is looking to break her doubles apart into a sidemount configuration because of a bad knee.

Sidemount can also be beneficial when you travel somewhere like the Caribbean and want to dive more than what a single 80 will allow.
 
You don't have to go into small passages to sidemount. Many cave divers sidemount and never go into passages not large enough to drive a car through. Many sidemount due to back and knee problems. Many sidemount just because that configuration trims out better. There are lots of reasons to dive sidemount.

Question; If you have to walk a long distance over uneven terrain such as up a shallow slew or to Buford through the swamp, where a hand truck would not be feasible isn't sidemount more of a pain than backmount?
 
i did buford with a sidemount diver. he wasn't a fan that day :)
 
It sucks, but I think it gets better once you figure out how to carry it all...

I'm thinking about rigging up some sort of crazy backpack(yeah, BM my SMs!) to get my tanks down to places with shallow/rocky sloughs and swamp. You could always make two trips, and it would be easy... but also take longer.

Long hikes with stable ground, I'd rather make two easy trips with single tanks. Getting up and down steep declines, much easier with singles.

Diving out of a little boat sucks in doubles, not just the loading/unloading, but also the gearing up part - especially when you can't touch bottom.

You can handtruck doubles as easily as two singles really...






... there's just so much more accessible cave with SM though :)
 
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