Short + Doubles = ?

[diveh3]

My primary type of diving right now is in Morehead City/ VA Beach ect.... I've only done the wrecks in <70ft, but im looking this summer to get into the deepers ones, maybe some of the subs. I know these are at like 120ish and I didn't want to get a stupid pony bottle, so I was looking at some doubles that I could make two good dives on, no deco. I dive in a dry suit most of the time, but sometimes a wetsuit in NC/SC. I actually have 2 72's a buddy is willing to give to me, but I know this won't be enough gas for 2 deep dives. I was also looking at AL80's, but I think if im going to spend the money I might as well do it right the first time. Also Doc, do you know if VAScuba rents doubles? Thanks for all the help, and if anyone is my height please tell me what your using!

My 2cents:
5'8" 180, I have 80s,120s,104s, but I the tanks I like best of all are the 80s.
You can dive em' dry, you can dive em' wet, You can dive em' on the internet.....oops to much Suess in my drink.
The 80s are cheap, easy to carry to the fill station, always avalible.....but if the 72s are free Nothing beats FREE.

 

[Tom Winters]

5'5"? - you would love twinned steel LP 66's. At 3500psi, you'd have about 165 cubic feet of gas. Or go for the steel 85's - at 3500psi, you'd have 226 cubic feet of gas.

 

[Unproductive]

My 2cents:
5'8" 180, I have 80s,120s,104s, but I the tanks I like best of all are the 80s.
You can dive em' dry, you can dive em' wet, You can dive em' on the internet.....oops to much Suess in my drink.
The 80s are cheap, easy to carry to the fill station, always avalible.....but if the 72s are free Nothing beats FREE.

Are you talking about Al 80's or steel?

Justin

 

[diveh3]

Are you talking about Al 80's or steel?

Justin

I am talking about the Aluminum 80s, especially nice in a wet suit - the posted bouyancy swing is -4 to +4 per tank x2 for doubles. Thus able to easily swim up in the event of a wing failure. So you need about 6-8lb of lead to make them neuteral on almost empty tanks. I achieve this by using a v-weight.

All my steels are still negative when empty and I won't dive them with a wet suit.
My 104s are around -14 empty and with the rest of my kit is just an unacceptable saftey range for me to swim up without additional bouyancy.
Diving dry with steel tanks your suit becomes the alternate source of bouyancy in a wing failure.

 

[DA Aquamaster]

I agree with Dive H3 on the problems with steel tanks in the event of a wing failure.

Double steel 72's are about as negative a tank as you want to use with a wetsuit. Just about every other steel tank (including the Faber 72's) can get excessively negative when doubled and can cause problems swimming up from depth in a wet suit following a wing failure.

If you are diving wet with anything other than aluminum 80's or steel 72's you need a redundant lift source such as a double bladder wing, two stacked on top of each other (the old low tech method of making a double bladder wing) or, at a minimum, a lift bag.

The biggest difference between rec diving and tech diving, and arguably the defining difference, is that in rec diving if you get in trouble you can always go directly to the surface, while in tech diving, you can't. Consequently, dropping weights under water to establish positive bouyancy is not an option in most technical diving situations as it will normally result in you acending all the way to the surface. That would be a very bad thing if you blow off 30 minutes of deco in the process.

 

[Jason B]

waterweasel, I have a pair of LP95's doubled that I'll let you take for a spin if you ever want to meet up at Lake Rawlings. Of course you'll need to bring a buddy as I'd be sitting topside while you dive them as they are all I have. A bunch of us are going to head up there this Sunday as a matter of fact - but another date will also work. Let me know.

Jason

 

[trieste]

I'm in a similar situation, but I am one step further. I own a pair of 130's that I currently dive as singles. (love 'em!) I had ordered 119's, but my lds said "hey! your 119's won't be in for a while, you can have these 130's for the same price!" so I bit. Now I have tried my buddy's double 119's and don't have an issue (I'm 5'7",175) But I'm not sure if the 130's will be too big or not.

 

[Snowbear]

... if anyone is my height please tell me what your using!

I'm 5'6". I use HP 120's as my main set of doubles. They work just fine for me, as do the E119's ad LP104's I've used.
If you can, I would suggest finding a generous buddy and trying some out before you buy any.