doubles worth it???

[RiverRat]

Lighten up a little on the sarcasm Curt. He has acknowledged he has not made it out of the pool yet and is just asking a couple of general questions. Nothing wrong with having goals.

I second that. I had many questions when I started and found the answers here on SB, not from the local shops or various other numnuts.

Let's see if we can help out inmate on main tank selection or something of value to get him off on the right track.

inmate, forget about doubles now. You could do like I did and get a PST E-7 100 with a convertable valve allowing you yoke or DIN connection and the ability to attach an isolator valve to double up your tanks in the future. Start thinking now about Aluminum versus Steel tanks and tank volume. My 100's have a nice reserve on deep dives and so far I have not doubled them up yet. No need yet.

 

[Don Burke]

thanks for the help that’s what I thought from reading other posts i think someone said something like doubles make you feel like a drunken turtle and by the way one of you worded it sounds like you need another citification for deeper dives is this true or not???

My doubles ride pretty well. If I try to use the drysuit for buoyancy with steel doubles, it gets pretty unstable, but that is the exception.

They are pretty handy for very long shallow dives. Without a nitrox cert, the extra capacity is not very useful beyond about 50 feet since you run into no-stop limits well before you run out of gas.

 

[Curt Bowen]

Lighten up a little on the sarcasm Curt. He has acknowledged he has not made it out of the pool yet and is just asking a couple of general questions. Nothing wrong with having goals.

Good, jump in there and teach him

 

[Wijbrandus]

I didn't take Curt's post as sarcasm or harsh at all. Rather, he cut right to the meat of the matter. Figure out the basics before worrying about advancing beyond them. Seems to me he hit the matter dead on. Those three are the hardest lessons for a new diver to learn.

 

[MXGratefulDiver]

I didn't take Curt's post as sarcasm or harsh at all. Rather, he cut right to the meat of the matter. Figure out the basics before worrying about advancing beyond them. Seems to me he hit the matter dead on. Those three are the hardest lessons for a new diver to learn.

Or even some old divers ... saw a guy in a rebreather crawling across the bottom on his knees the other day. Ten minutes later we swam past him on our return, and he was still crawling on his knees. I'm fairly sure this guy has logged some significant bottom time ... but obviously hasn't worried much about the basics yet.

The lime green roofer's knee pads were very fashionable, though ...

... Bob (Grateful Diver)

 

[wedivebc]

Or even some old divers ... saw a guy in a rebreather crawling across the bottom on his knees the other day. Ten minutes later we swam past him on our return, and he was still crawling on his knees. I'm fairly sure this guy has logged some significant bottom time ... but obviously hasn't worried much about the basics yet.

The lime green roofer's knee pads were very fashionable, though ...

... Bob (Grateful Diver)

Mabe he was looking for a contact lens. Don't be so judgemental

 

[Curt Bowen]

Or even some old divers ... saw a guy in a rebreather crawling across the bottom on his knees the other day. Ten minutes later we swam past him on our return, and he was still crawling on his knees. I'm fairly sure this guy has logged some significant bottom time ... but obviously hasn't worried much about the basics yet.

The lime green roofer's knee pads were very fashionable, though ...

... Bob (Grateful Diver)

Yes for those of us who own a rebreather, your bouyancy skills go right out the window the first couple times you try one. No matter how many dives you have had in the past. I know, my bouyancy skills on OC are very fine tuned (within 1 inch). But on my new meg rebreather, i still have a little trouble sometimes.

 

[mempilot]

Doubles probably aren't worth it for recreational divers - that much gas means you're going to stay down longer or go deeper than recreational allows. They're expensive, harder to manage and of limited value.

In general, this is true. However, smaller doubles are available. You can double up any size tank to get the redundancy of 2 first stages.

Considering a proficient diver in the proper state of mind and health can demonstrate a CESA from 60', one might consider that the redundancy isn't neccessary from 0 to 60'. If a good buddy is available and the diver is proficient, this may be enough contigency.

AOW divers venturing beyond 60' may choose to have another form of redundancy. This could come in the form of a buddy, but also in the form of a pony bottle with sufficient gas supply to get them safely to the surface from 130 or shallower. I'd prefer to dive small doubles in this case to maintain a balanced rig. A set of double 72's or even double 45's might make a better option than messing with a pony.

I made the transition from standard singles to large singles with an h-valve to doubles. The progression was logical based on the depths and occasional solo diving I was doing. Being proficient on whatever configuration one chooses is paramont in making it safer than just using a large single.

Even Tom Mount claims to use double 45's on occasion for dives where one could use a large single with an h-valve. (Technical Diver's Encyclopedia)

 

[dilligaf368]

I used to dive doubles in the Navy and one thing no one has mentioned is the drag on the unit itself. It's much easier swimming with a single than doubles. Less drag and less hard breathing to get where You want to go..

 

[mempilot]

I used to dive doubles in the Navy and one thing no one has mentioned is the drag on the unit itself. It's much easier swimming with a single than doubles. Less drag and less hard breathing to get where You want to go..

Very true. I guess it depends on the type of diving you do and where. I do a lot of wrecks where it is easier to get away from the current. Simple sculling is used to maneuver in and about the wreck, so there isn't a lot of expended energy.

For someone diving the open unprotected bottom in a current, even smaller doubles could be too much drag in some cases.