Tiny Doubles and Tech question

As a petite female I am exploring the idea of tiny doubles. I have a three part question.

First, how would I go about setting it up; what tanks, wing options, etc?

Secondly, as an alternative, would it be realistic to use a single tank for back gas, then sling 1 or 2 30 cf or 40 cf tanks?

Last, would either of these options be acceptable for starting entry level tech courses? Assuming of course that the available gas works for the dive plan.

I've seen double 53 aluminum, of course double 72 steel are common. Double 64's would work, but the 53 and 64 would be hell to trim, unless you're REALLY petite. Since 64 are the same dia as 80, you can use same bands and manifold, wing based on your size and thermal protection.

You don't use a single for back gas because of redundancy, not volume or weight.

the biggest issue with tiny doubles when starting in tech is, the gas you are carrying is not just for you. you need to have enough gas to get you and a team-mate to safety. So keep that in mind when choosing tanks as your teams highest sac will determine dive times, etc....

Like wookie said, steel 72s have worked great for me in both backmount and sidemount.

That being said, tiny doubles are nice, i would avoid single back mount tank and stages.....if you want to do that, have a look into a sidemount set up.

I would find a tech instructor that you would want to train with and have a chat with them

We've never met Wookie, but I never pictured you as a "petite woman"...

I have a couple of buddies here that are tiny women... more short, but solidly built... How "petite" is "petite"? The reason I ask is that I think weight is the issue... most sets can be trimmed out somehow, but if you can't lift them, what's the point? I think it also depends on the sort of diving you do... boat vs shore. I wear twin 130s often, but would never consider a shore dive in them!

So one of my friends is (my estimates) 5'2', maybe 120# and quite muscular. She wears twin steel 100s and I think twin Alu 80s when cave diving. The other is about the same height, but probably 140#... not necessarily all muscle. She is also in steel 100s, and so on. Personally, I don't understand why they use tanks that large for most of their diving, which is all open water. My "regular" tanks are twin steel LP 80s and I can easily get two normal dives ("Normal" up here being maybe 160'/25 BT or 110'/25 BT sorta thing. Typically we would carry a deco gas in a 40 or 80 as well).

We use steels mostly for their buoyancy characteristics since we're all diving dry, and in fresh water.

My better half is 5'3, 100# soaking wet. She currently dives a single steel LP 80 but is looking at double. She isn't especially strong, but I think even my 80s would be brutal for her. We might look at 72s or 65s possibly...

If you have any ability to try some stuff before you commit that would be good too. Poorly trimmed tanks are a pain, so a lot hinges on your height as well.

And look hard at S/M. My 58 year old back is looking that way more and more. The savings at the chiropractor should cover the new gear.

If it works out for you, you're going to end up with a rebreather, so you might as well start there. It will save you a pile of cash in the long run. Rent a rb and train on it. If you like it, continue to rent it until you can buy one.

uncfnp:

As a petite female I am exploring the idea of tiny doubles. I have a three part question.

First, how would I go about setting it up; what tanks, wing options, etc?

Secondly, as an alternative, would it be realistic to use a single tank for back gas, then sling 1 or 2 30 cf or 40 cf tanks?

Last, would either of these options be acceptable for starting entry level tech courses? Assuming of course that the available gas works for the dive plan.

Click to expand...

Sidemount would work nicely too. You can easily use a couple of smaller steel or aluminum tanks.

One thing to keep in mind is that even if you only use a tiny bit of air, you still need to have enough to get your buddy back to the surface in an emergency. Don't buy any equipment until you've talked with your instructor,. He can explain what you need in much greater detail.

Depending on where you get your fills...will they do cave fills on LP tanks?
If the answer is yes, LP 45's (2640psi rated) doubled and twinned with a "cave fill to 3500psi" is ~120 ft3.
They are small and manageable...I use them for quick little rec dives with buddies using AL80/HP100 singles. Even if I can't get them cave filled at home all the time...it's still 90 ft3 of totally redundant gas.
My grandson will be playing with these in the pool this summer, he can handle them...he's 8

Thanks guys. I'm 5'3, a little on the older side and average weight/fitness but a bad right shoulder with limited lift and ROM.

Wookie, the RB would be great but my "tech" diving plans are actually pretty limited. I'm looking mostly for a way to make my rec dives safer and hopefully get on the NC wrecks for more than 8 mins with a conservative DC.

The advantage of the standard tank with slung stages is cost. I can pretty much do this with my current gear. And for only a few times a year, that is pretty attractive. Because of health concerns, my dives will never be deep into tech or for any extended length so I think it might be possible for me to carry enough gas for my buddy this way.

It's true though that SM might be better than the tiny doubles but will a tech instructor that dives doubles tech a student in SM? And will I need a formal SM course or can a relative intelligent diver pick this up on her on?

The one instructor I spoke with only wanted to teach me if I invested heavily into "tech gear."

I'm 5'1" and I dive single HP80s (great little tanks - I have 3) as often as possible.

When I started in doubles I first used LP72s and felt they were overwhelming. (First day ever in doubles Jan 2010)



I later started cave training and was told by one of my instructors that few would dive with me unless I was carrying enough gas such as LP85 pumped to cave fills - even though I have a low SAC rate.
And in just a few dives of practice, these are now my preferred tanks in a drysuit. They do trim out nicely, and I've learned how to move in them (carry the weigh on my hips). The important thing with doubles is the weight of the regs and manifold had me face planting. Moving to the longer tanks, further down my back, wing further up the plate, I was finally able to balance out and have OK trim most of the time. (Oct 2012)



For warm water here in the Keys, I dive AL80s in rash guard or shorty or wetsuit. (me on the left)


If I can do it at 51, you can too. It's really about distributing the weight so it works for your horizontal trim, and then practice to getting used to it. And no I'm not particularly strong.
Yes, after a long dive, many times I sit and rest before moving tanks (or get help from my sherpa )
It's been a long slow process for me (not something I ever felt compelled to rush). Once you are able to remain in horizontal trim you don't notice the difference. I've learned from watching nad reading other short women like TS&M.


Here is another discussion on tiny doubles http://www.scubaboard.com/forums/tanks-valves-bands/449338-tiny-doubles.html

Good luck with your choices and growing into your technical diving.

---------- Post added January 8th, 2014 at 10:35 PM ----------

One more comment...if you are concerned with the weight of tanks on your back, why not just go straight into sidemount. That way you only carry one tank at a time to the water and gear up in the water. On a boat, you just unclip the tanks and pass them up one at a time.

I'm staring 60 hard in the face, and I'm 5'2" and nothing anybody ever considered athletic.

I started with double 72s, and I hated them, and hate them to this day. I cannot trim out the things, and honestly, they are not that much lighter than bigger tanks. The first time I put on a set of Worthington 85s and got in the water, I took a deep sigh of relief and thought, "I've come HOME!" I still like the 85s better than any other doubles I have dived, although double HP100s trim out very similarly, and so do double HP 130s -- but you lose about a half inch of height if you have to carry those very far.

Like the man who lifted the calf every day . . . if you start with relatively small tanks, like 85s, you will soon find that you can grit your teeth and schlep something bigger. But unless I absolutely need the gas, the biggest doubles I'll wear are 85s, or Al80s in Mexico.