Doubles?
- Thread starter johnx15
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Rainer
Contributor
How about spending it on going diving and gaining experience. Just saying...
Oh good lord, just answer the man's question.
The center to center spacing on either 7.25" or 8" tanks is usually around 210mm to 220 mm. Most isolator manifolds will fit most tanks in suitable bands.
They come in basically two flavors - face seat and barrel o-ring varieties. OMS sells a face seat manifold and it has two large hex bolt looking connections on each side of the isolator - similar to the old cone seat manifolds used back in the day. They are not adjustable as the center to center distance is what it is.
The barrel o-ring manifolds have a thinner looking crossbar that screws into the left and right valves and the seal comes from two o-rings that seal inside a barrel that allows a lot more range of adjustment to accommodate different bands. Most people go with that design and several companies sell them.
Diving doubles is not magic nor is it a real problem to use them on recreational dives. I normally take double 100's on boat dives and just use half on the first dive and half on the second and don't have to bother changing tanks.
The only cautions are that you do have a lot of gas that can get you into serious deco, and you really need a BP wing to provide good stability with them. The swing weight is also twice as much as rather than 5 lbs of gas on baord, you have 10 or 12, so you will get a lot more buoyancy shift from full to empty.
The center to center spacing on either 7.25" or 8" tanks is usually around 210mm to 220 mm. Most isolator manifolds will fit most tanks in suitable bands.
They come in basically two flavors - face seat and barrel o-ring varieties. OMS sells a face seat manifold and it has two large hex bolt looking connections on each side of the isolator - similar to the old cone seat manifolds used back in the day. They are not adjustable as the center to center distance is what it is.
The barrel o-ring manifolds have a thinner looking crossbar that screws into the left and right valves and the seal comes from two o-rings that seal inside a barrel that allows a lot more range of adjustment to accommodate different bands. Most people go with that design and several companies sell them.
Diving doubles is not magic nor is it a real problem to use them on recreational dives. I normally take double 100's on boat dives and just use half on the first dive and half on the second and don't have to bother changing tanks.
The only cautions are that you do have a lot of gas that can get you into serious deco, and you really need a BP wing to provide good stability with them. The swing weight is also twice as much as rather than 5 lbs of gas on baord, you have 10 or 12, so you will get a lot more buoyancy shift from full to empty.
JDMerk
Contributor
Real men dive the Navy tables
Seriously though I didn't have the PADI tables in front of me and didn't feel like looking them up, but I know Navy by heart. My point still stands...at that depth the NDL is a long LONG time.
why not just invest in a larger single tank (if you said why already and i missed it i apologize)..
I use HP100s and they are great! you can get a 120 which will give you plenty more gas, but still maintain the single tank setup.
I use HP100s and they are great! you can get a 120 which will give you plenty more gas, but still maintain the single tank setup.
crpntr133
lost, even with a compass
Personally I think you might be getting in a little over your head especially for having between 0-24 dives logged. But I'm sure that you know more then all of us by your post.
Diving doubles is a whole new ball of wax. I have had several people try mine out and changed their mind really quick about diving doubles. Once you get use to it and know what you are doing (which you already know from you post) then they are easy.
If you do go doubles make damned sure that you can do a valve drill. I learned from personal experience that this is a must, not an option. This is especially true if you are going to be pushing the NDL where a CESA make not be the best idea.
Diving doubles is a whole new ball of wax. I have had several people try mine out and changed their mind really quick about diving doubles. Once you get use to it and know what you are doing (which you already know from you post) then they are easy.
If you do go doubles make damned sure that you can do a valve drill. I learned from personal experience that this is a must, not an option. This is especially true if you are going to be pushing the NDL where a CESA make not be the best idea.
Blackwood
Contributor
crpntr133
lost, even with a compass
And from his original post he knows all about diving.
Sorry dude but you deserve it for posting something like that with 0-24 dives logged.
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