how to go about it

[edward]

I fancy getting some redundancy, and thought about a pony, but if I'm going to buy a new 1st/2nd stage, I got to thinking that I could just run independant twins.

So...... Being a tight git, I already have 2x15l cylinders, and BCD with 25kg lift (a 'wing style' seac sub pro 2000). I guess you can see where this is going......

How about buying twinning bands, a new 1st/2nd stage and a new pressure gauge, and running it on my existing BCD??

I'm 6'1" and 15st, my SAC is not great, hence using a single 15 up till now.

Comments? will I be able to lift it? will the BCD die? Am I barmy?

If you think I should just save up and get a 'normal' twinset and wing, don't be afraid to say so.

[And]

Originally Posted by edward

If you think I should just save up and get a 'normal' twinset and wing, don't be afraid to say so.

Twin 15's will kill the BC, and I don't think will help you progress comfortably. If going for twins I'd recommend 12's, not 15's.

Andy

[Mark Chase]

25kg of lift or 25lb of lift?


My M8 used to run twin 12 on a Buddy Comando BCD without a problem. I ran 12s on a Seaman Sub Black Jack. There isnt much in water weight diferance between 15s and 12s so it wil be OK there but on the surface you might find it a bit lacking.

The stage cylinders will be the last straw. They were for me.

ATB

Mark Chase

[RichClark]

You've probably got *just* enough lift in your BC. That being said, I don't think that you'll find it particualry comfortable, and it may stop you from progressing your diving further.

I have twin 12's and twin 15's, and to be honest the 15's are a git out of the water, and are only a tool for the job.

If you've decided that twin set is the way to go for you, I'd seriously consider buying a new wing and twin 12's. You could probaly pay for most of this my selling your current BC and 15's on eBay

Cheers

Rich

[edward]

thanks for replies so far.

Mark - it is 25kg, not lb. I suspect this is only just enough, though.

I have got 2x12l dumpies that I could use (but they are really the wife's!) I guess that would be better

It's beginning to look like I'll have to save up for a 'proper' twinset, but I think that in all honesty I knew that already! I don't really want to sell the BCD etc as it will get used on holiday, with groups etc.

So, with that in mind, I'll want twin 12's, but should they be indies, manifolded, what wing etc. How about second-hand?

Cheers

[And]

Edward, what type of diving are you wanting to do?

[Jules]

I know people do it but in my opinion 12 litre dumpies will be horrible. Too short and wide. Twinsets should be 12s or 7s as they are both tall enough to be able to reach your valves to do shutdowns. I had twin 10s and it was hard to reach the valves (and hence the whole twinvert scenario..)


you can buy decent twin 12s for silly money sometimes, stevil got manifolded twin 12s at SDS for 300 quid.

In my opinion manifolded 12s are the best option for a gas guzzler but where you live and what diving you do will help people give you better advice.

Jules

[Lawrence Debono]

I had a pair of 10L Steel tanks (low pressure light weight) that I had attached to the Scubapro Night hawk. This only has 20Kg or 45 lb (something like that). I also used to carry a 4 liter aluminum for deco gas, on the same rig. I never had problems with that. It was light and manageable.

Now I'm using twin 16 liters, and they are back busters. I use a 100lb lift OMS wing for that. This comes handy especially when I have the stages attached (12L / 180 bars (lighter than normal 12's)). Even in the water I feel my back arching. If you want redundancy and lots of gas you have to pay for it some how.

Make sure you have another way of inflation if you rig up the twin 15 L. Use the dry suit or a 2nd bladder.

Lawrence D

[Noel Johnson]

Hi Edward,

I have a pro 2000 as well and was looking into twinning up on it. I spoke to John Camm of Seac Sub (who incidentally designed it) and it was designed as a sort of cross over BCD if you will. He uses one with twin 10 300s so a pair if 12s would be no problem. SDS will make a latching system for you as well but you could use twinning bands. The Buddy ones won't work on this jacket BTW.

The 25 kilos of lift is sufficent for 12s but I'm not too sure about 15s. I dive on twin 12s now but with a stainless plate and wing as I had one as well, although the Pro 2000 is going to the Red Sea with me in August and I'll twin up with it out there.

HTH or indeed makes sense,

Noel.

[Scuby]

I know someone who dives with twin indy 15's with a back mounted pony on a Buddy jacket... maybe not the best setup in the world, but it works, although he really is quite a big bloke and so lifting it isn't a problem for him.

I used twin 12 dumpy's for most of the summer (again independent) and didn't have a problem with them. Perfectly comfortable in the water. The DO of one of the clubs i'm a member of uses them all of the time, including 60+m trimix stuff. He uses them on a wing obviously, but I had mine on a normal (Cressi) BCD.

I would say that I do now have manifolded tall 12's, but the dumpy's weren't a great problem. If you can use them for now before you change to something else then i'd say go for it - and its probably going to be easier than using the 15's. Thats what I did - went from single -> single + pony -> independent dumpy 12's -> manifolded tall 12s. The only thing i'm left with that I don't regularly use now is the pony (which will get used as deco later) and a dumpy 12 (which I will use when i'm in Stoney teaching or in the pool, that kind of thing). That route did however mean that I broke down the cost of buying kit significantly, doing it over a long period when I could afford it rather than all together, and with no particular disadvantages to doing it.

David