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BoomerNJ
10-09-2007, 08:50
I know I will be diving doubles eventually & most likely they will be steel tanks. My BCD is a Zeagle Brigade that will hold 19liter doubles with just an adapter plate, as per the tag inside it. I want to make sure if I buy a tank now I buy the right size to add a second one in the future & have at least 2 119 cu ft steels to dive. What is the conversion of that 19L to cubic feet? I have searched the forums & can't find an answer...

Any help would be appreciated! If there is an answer on here & I missed it, I apologize! The only formula I could find comes to a 0.6709... number.

Thanks!

Boomer

Disregard, I think I found my own answer. A 19L tank is roughly 150 Cubic Feet. WAY more than I'll ever wear...

Thanks for looking anyway!

in_cavediver
10-09-2007, 11:30
I know I will be diving doubles eventually & most likely they will be steel tanks. My BCD is a Zeagle Brigade that will hold 19liter doubles with just an adapter plate, as per the tag inside it. I want to make sure if I buy a tank now I buy the right size to add a second one in the future & have at least 2 119 cu ft steels to dive. What is the conversion of that 19L to cubic feet? I have searched the forums & can't find an answer...

Any help would be appreciated! If there is an answer on here & I missed it, I apologize! The only formula I could find comes to a 0.6709... number.

Thanks!

Boomer

Disregard, I think I found my own answer. A 19L tank is roughly 150 Cubic Feet. WAY more than I'll ever wear...

Thanks for looking anyway!

I wouldn't say a pair of 150's is out of line. The LP equivalent is the old LP120's and I know many divers who dive those.

All of that said, for carrying big steel doubles, a good BP/wing setup is hard to beat. (personal opinion)

CompuDude
10-09-2007, 12:14
I don't know many serious doubles divers who dive doubles in anything other than a bp/w. The Zeagle will work, but it's not ideal.

BoomerNJ
10-09-2007, 12:21
Thanks in_cavediver! Yeah, I know the bp/w set-up is the way to go for tech, but if you've never seen a Zeagle BCD, it's as close as you can get to that in a weight integrated BCD, in my newbie & completely uninformed opinion. I can actually add a backplate to it & it has attach points for the additional straps already there. Plus it uses interchangeable bladders, with up to 85lbs of lift. So basically I though it would be a good starting point for me until I go completely tech after a few years of rec diving experience...

Again, I really appreciate your input though. I have a LOT to learn yet. I haven't even begun to scratch the surface yet...

Boomer

BoomerNJ
10-09-2007, 12:34
Hey CompuDude, thanks for your input as well!

fire diver
10-09-2007, 12:34
Please don't take this as a slam, but you should probably stick to singles for a bit longer. If your profile is correct, you have a lot to learn about improving your bouyancy. Moving to doubles, especially LARGE double steels, you will have about 4 times the bouyancy problems as a single.

Start small and get used to it. Then move into doubles in a year or two. Also, why do you want such large tanks? Do you realize just how large 300 cubic feet of back-gas is? What are your goals in diving?

FD

somewhereinla
10-09-2007, 12:48
I think 300 cf is a bit much as well, I don't think I have ever seen someone with such a rig... If you go double, it might be a good idea to buy both tanks at the same time as it can be challenging to find 2 tanks the exact same eight. You want to get 2 tanks with close serial numbers.

CompuDude
10-09-2007, 13:13
I think 300 cf is a bit much as well, I don't think I have ever seen someone with such a rig... If you go double, it might be a good idea to buy both tanks at the same time as it can be challenging to find 2 tanks the exact same eight. You want to get 2 tanks with close serial numbers.

I agree. Expedition-class cave dives may justify such extreme gas requirements, but in general, a nice pair of HP100s is a great starting point for doubles... 200cf of gas is a LOT. I agree with the recommendation of getting some more recreational-level experience first, however, before rushing into doubles.

If you want to prepare yourself for doubles down the road, it might not be a bad idea to pick up a matched pair of HP100s and have a blast diving them as singles for a while, then you can double them up when the time is right.

texdiveguy
10-09-2007, 13:15
Thanks in_cavediver! Yeah, I know the bp/w set-up is the way to go for tech, but if you've never seen a Zeagle BCD, it's as close as you can get to that in a weight integrated BCD, in my newbie & completely uninformed opinion. I can actually add a backplate to it & it has attach points for the additional straps already there. Plus it uses interchangeable bladders, with up to 85lbs of lift. So basically I though it would be a good starting point for me until I go completely tech after a few years of rec diving experience...

Again, I really appreciate your input though. I have a LOT to learn yet. I haven't even begun to scratch the surface yet...

Boomer

Boomer........... do your homework on those twin cylinders....as suggested try out several sets/sizes....there are several factors that go into selecting and diving doubles. No rush...take your time---have FUN!

Your Zeagle Brigade will provide an ok platform for doubles...I would suggest you look at using a full b/plate with it instead of the 2 small plates they suggest, will give you a better 'ride'.

As to 'serious' sport/technical doubles divers only using bp/w gear set-ups that is not an accurate assumption.....I persl. dive a Zeagle Tech/65lbs. with wonderful results in various dive conditions....granted this bc is a bit different than a Brigade,, and I did add a butt ring for trailing cylinders. I use this bc for diving a large st. hp130 single and it works great....would not recomm. the Zeagle Tech for smaller or Al singles in general though....its design better suites it for large singles or doubles.

Good luck.... :-)

BoomerNJ
10-09-2007, 13:15
Thanks somewhereinla & texdiveguy! There is a lot more to consider with this than I origionally realized. I am thinking I might just get a neutral 80 for now. I'm getting 40 - 50 minutes out of that size tank & not doing anything deep or any penetration dives yet. So I thinks it's best just to hold off on steel until I can afford to get two at one time...

texdiveguy
10-09-2007, 13:22
Thanks somewhereinla & texdiveguy! There is a lot more to consider with this than I origionally realized. I am thinking I might just get a neutral 80 for now. I'm getting 40 - 50 minutes out of that size tank & not doing anything deep or any penetration dives yet. So I thinks it's best just to hold off on steel until I can afford to get two at one time...

At least you are on track with a plan and the motivation to search out options and ideas....!

CompuDude
10-09-2007, 13:24
Thanks somewhereinla & texdiveguy! There is a lot more to consider with this than I origionally realized. I am thinking I might just get a neutral 80 for now. I'm getting 40 - 50 minutes out of that size tank & not doing anything deep or any penetration dives yet. So I thinks it's best just to hold off on steel until I can afford to get two at one time...

You may want to read this thread before buying a neutral 80:

http://forum.scubatoys.com/showthread.php?t=2335

texdiveguy: Re my comment about "'serious' sport/technical doubles divers only using bp/w gear set-ups", if you re-read what I wrote, I said "not many". I didn't say there weren't any. Serious question: Do you really think a significant number of serious doubles divers are using your setup, or would you grant that a significant majority are using a bp/w?

texdiveguy
10-09-2007, 13:29
Thanks somewhereinla & texdiveguy! There is a lot more to consider with this than I origionally realized. I am thinking I might just get a neutral 80 for now. I'm getting 40 - 50 minutes out of that size tank & not doing anything deep or any penetration dives yet. So I thinks it's best just to hold off on steel until I can afford to get two at one time...

You may want to read this thread before buying a neutral 80:

http://forum.scubatoys.com/showthread.php?t=2335

texdiveguy: Re my comment about "'serious' sport/technical doubles divers only using bp/w gear set-ups", if you re-read what I wrote, I said "not many". I didn't say there weren't any. Serious question: Do you really think a significant number of serious doubles divers are using your setup, or would you grant that a significant majority are using a bp/w?

No--- I was not picking at your post-- I read your post....but I hear this generalization all to often....as to your question as to the number of divers wearing a bp/w verse a set-up as mine....no doubt the bp/w wins out in numbers....but it is not the only viable kit for doubles and/or technical diving.....I would say my kit falls into the 'hybrid' catagory of gear set-ups....a set-up like mine and others of similar type has no bearing on your diving performance being deminished or changed. IMO :-)

BoomerNJ
10-09-2007, 13:37
Thanks CompuDude! Glad all you guys are around to keep me from wasting $$$ on things I don't know enough about!

in_cavediver
10-09-2007, 20:42
I think 300 cf is a bit much as well, I don't think I have ever seen someone with such a rig... If you go double, it might be a good idea to buy both tanks at the same time as it can be challenging to find 2 tanks the exact same eight. You want to get 2 tanks with close serial numbers.

I agree. Expedition-class cave dives may justify such extreme gas requirements, but in general, a nice pair of HP100s is a great starting point for doubles... 200cf of gas is a LOT. I agree with the recommendation of getting some more recreational-level experience first, however, before rushing into doubles.

If you want to prepare yourself for doubles down the road, it might not be a bad idea to pick up a matched pair of HP100s and have a blast diving them as singles for a while, then you can double them up when the time is right.

Wow, I must be an expedition cave diver because I am seriously looking at getting a set of the 149's to go with my 104's (I treat as 130+). I know MANY divers including a few women who use LP120's as side mounts and back mounts. They are big but not huge or impossible to handle. I could see saying cave divers want as much gas as they can handle because gas = life.

That said, for OW tec diving, LP85's/HP100's are sweet tanks. I'd also second the buy the tanks together as matched set. Its easier to get similar heights that way.

Lastly, I am familiar with Zeagles. I dove a Ranger before the BP/W. I've also dove the zeagle plate with ranger wing and it just didn't work well. OW instructor friend dove the tec and tec packs before the BP/W. I'll stand by the big steel doubles is best on a steel BP. (choose whatever harness you want though)

BoomerNJ
10-10-2007, 05:02
Please don't take this as a slam, but you should probably stick to singles for a bit longer. If your profile is correct, you have a lot to learn about improving your bouyancy. Moving to doubles, especially LARGE double steels, you will have about 4 times the bouyancy problems as a single.

Start small and get used to it. Then move into doubles in a year or two. Also, why do you want such large tanks? Do you realize just how large 300 cubic feet of back-gas is? What are your goals in diving?

FD


Hey FD,

I def. don't consider that a slam, I know I have a lot to learn. I was looking into this only because I know I will dive doubles someday, not in the near future though. If I was going to buy a steel tank, I wanted to make sure it would fit my BCD if I changed to doubles, so I don't waste money on something that expensive. My original question was just about what size a 19L tank is in cubic feet. I figured that out though on my own. And I def. don't want tanks that large, as I mentioned in the original post. Maybe someday way down the line, but not any time soon. One of my main goals is wreck diving here in Jersey. That means some deep diving to get to some of the more interesting wrecks here, so doubles is almost required to have any usable amount of bottom time. Thanks again FD & I really appreciate everyone's input!

Boomer

PaDiver93
10-22-2007, 14:40
Thanks CompuDude! Glad all you guys are around to keep me from wasting $$$ on things I don't know enough about!


I love my Zeagle Ranger, but the type of diving that I do (NJ) - BP/W set up is more minimalistic and allows to take more equip. down. Ranger is perfect for a single tank. With doubles I would go for a BP/W (Next year prolly).

MSilvia
10-22-2007, 14:54
You might consider getting a couple of used lp72s. You should be able to get them cheap, they double up nicely, have great buoyancy characteristics, and will give you a lot of additional gas, true redundancy, and something reasonable to get used to doubles with.