Economical doubles?

[FIXXERVI6]

I know a few people who dive the Double 80's here in a quarry. If its enough gas for the dive there should be no problem. Use what you got.

Double aluminum 80's are great for a lot of things, quarries included but as stated by other posters 1/6 of aluminum 80's in a cave like JB or Ginnie is going to be a very short dive.

Lots of work with very little return in fun, I'd doubt you'd even have enough time to get into the "groove", also keep in mind caves like JB if your swimming, running a reel and not used to it, your sac is going to be WAY above .6

 

[DA Aquamaster]

I guess I left out that I want to get used to diving doubles before I take the courses next winter. I will upgrade my equipment when it becomes a necessity but until that point I want to try and figure out what is what. The side benefit is when we come down for our trip we want to hit the Oriskany or the Spiegel Grove or both. And with those being deeper dives we get more bottom time (I realize it's minimal due to deco stops) but non the less it is more. But until I need to upgrade I just wondered if it was practical to use my AL80s.

As you've noted, everyone has an opinion and will keep posting them long after the ground has already been covered.

There are also differneces of opinion that you will encounter so you need to consider what you find on the internet very carefully, and if in doubt, take the most conservative approach.

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What you suggest you want to do makes sense. If all you are doing is getting comfy in doubles, AL80s will work ok until a good deal comes along, but while you can re-use the manifold the bands are probably a lost cause so don't get too carried away with really expensive bands.

I agree that you do not want to show up for an class in doubles until you are very comfortable in them and have the kinks worked out of your configuration. An intro to tech/doubles class may help but it is not required if you can find a competent technical diver who can help you out. But be careful not to get too far from a standard Hog/DIR configuration. That configuration will serve you well as it will be acceptable to nearly any instructor. Once you get your configuration squared away, practice until you have perfect stability and buiyancy, then sign up for a Cavern class, or take Cavern and Intro to Cave/Basic Cave together. Then take a year or so to dive at the Intro level before taking Full Cave to gain real world experience.

Deco goes hand in hand with Full Cave in most cases, so it also helps to get Advanced Nitrox and Deco Procedures out of the way. A good alternative is to take Advanced nitrox pre-full cave and then take Deco Procedures post full cave from one of the few instructors that teach it in a full cave environment.

Sidemount is still all over the road in terms of anything that could be interpreted as a standard configuration, so my best advice is find someone who actually knows their stuff regarding sidemount in a cave environment and work with them. A couple sessions up front will save you months of diving on your own to try to sort it out.

If you are just getting into sidemount, consider a Nomad. You'll probably pull off all the pads and floaty crap, maybe a couple D-rings and then probably swap locations between the inflator hose and dump valve, but what results is very workable and very flexible and is suitable for a wide range of sidemount applications, tank sizes multiple stages, etc. If you do decide to go sidemount the same cautions apply - get the configuration sorted out and get very good in it before you show up for a class.

 

[ucfdiver]

besides, I've got 1.5 hour dives while using my 72s as primary backgas in caves that dip into the 100'+ range. Sometimes a good SAC rate will carry you through a longer dive - granted, that was while diving sidemount with a sidemount buddy where gas matching isn't a priority... and deco happened on seperate cylinders all together.

Well, under the right circumstances, I can go to the heinkle and back in 40-45 minutes with a stage bottle and never touch back gas....but for 90% of FL cave diving and buddies out there, large steels are by far the best choice

 

[hudson]

oops, double post

 

[hudson]

Not trying to sling mud or start anything, but in my opinion if your going this cheap then you really shouldn't be considering cave diving, and flipping a reg up to be exposed to bashing is bad news no matter how you slice it. I would be suprised if an instructor allowed such a config.

Good point, but the way I read the OP's post initially I figured he wanted to put together something quickly and cheaply to practice with, not take into training and caves. As others have noted, in addition to the exposed reg issue, it's not practical due to lack of sufficient gas, and sidemount is a better way to do independents. I also suspect quite a few instructors would not teach in independent doubles, period.

(Although, in retrospect, it may not be worth much even for training anyway, especially if one were to switch to a manifold later on.. the weight will be wrong, trim would be off, hose config would be different, gas management would be different, drills would be different...)

 

[Dive-aholic]

If you're already considering sidemount then skip the backmount and save yourself some money. No need for an isolation manifold or bands. Get a couple of 3lb weights and cam bands and the 80s will mimic small steels as far as weighting goes. Just make sure the instructor you choose can and will teach in sidemount. There are only a few of us who do teach in sidemount.

 

[SuPrBuGmAn]

Well, under the right circumstances, I can go to the heinkle and back in 40-45 minutes with a stage bottle and never touch back gas....but for 90% of FL cave diving and buddies out there, large steels are by far the best choice

??? 90% of both caves and divers eh?

Sorry, but if the dive at hand is doable with 72s with enough conservatism to be safe; then I'm not gonna bring the 95s down with me.

I probably use my 72s 30-40% of the time, they're great. I wish they were 85s, but I'd be hard pressed to get a set of those for free.





Not everything in FL has a raging flow, nor is everything deep. Even when it is... sometimes smaller tanks can still work under the right dive plan - not everyone is running to dive their absolute maximum allowable gas turn pressure.

 

[T. Bix]

Hudson, Yes you were right I do want to get used to diving doubles before I take my course but I want to do it right.

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

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.

 

[CamG]

Greetings T Bix most of the issues have been covered pretty well and you can make your own mind up. Several of the key things mentioned are the gas requirements for the class and the instructor waiver to train in doubles. It would be a good idea to contact or seek out a instructor to give you guidance. Different training agencies have specific guidelines. You will be allowed to use 1/6 of doubles for the training which will be a factor with AL 80's you will want to consider carefully.
Having just returned from cave country with Cavern / Intro. Cave certification I was amazed that you can rent doubles no problem. I have my own sets of LP 95's and HP 100's. I trained in the 95's always had plenty of gas and with turn pressures at 3000 psi I did not get as far as I would have liked. I am not telling you this to sway you away from the 80's but help you to understand the difference between OW and Cave.
Gas rules are not BROKEN ever. I was used to running 1/3 in OW but became to understand why training was done in rules of 1/6. Thus gas management becomes a factor.
I have found some pretty incredible deals on doubles as others have mentioned.
One thing I feel is a bonus using Steel is not having to wear a weight belt.
With your time frame you have plenty of time to research and weigh your options.
In your area there are lots of gear options new and used. Try your local dive clubs they are great places to find good used gear. When looking at steel always check for current vis inspection and Hydro stamp even if the tank is new. If you are not sure have the tank visually inspected. It can provide a good piece of mind.
Good luck what ever you choose and have fun. 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!

 

[ucfdiver]

??? 90% of both caves and divers eh?

Sorry, but if the dive at hand is doable with 72s with enough conservatism to be safe; then I'm not gonna bring the 95s down with me.

I probably use my 72s 30-40% of the time, they're great. I wish they were 85s, but I'd be hard pressed to get a set of those for free.

Not everything in FL has a raging flow, nor is everything deep. Even when it is... sometimes smaller tanks can still work under the right dive plan - not everyone is running to dive their absolute maximum allowable gas turn pressure.

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?