Small Doubles?
- Thread starter rds4640
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pescador775
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Northeast Scuba Supply will custom make high quality SS bands for your 45's for about a hundred bucks. Just tell them the exact tanks and manifold.
Alternately, buy some galvanized twin 38's, 40's or 50's with 3/4 neck. EBay has them fairly regularly. Nice set up and properly spaced (6.9" dia) with standard bands and manifolds (verify centers for specific manifold.
Alternately, buy some galvanized twin 38's, 40's or 50's with 3/4 neck. EBay has them fairly regularly. Nice set up and properly spaced (6.9" dia) with standard bands and manifolds (verify centers for specific manifold.
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metridium once bubbled...
Double AL 40s?!?!
I was actually thinking about this for my little boy. They would size just right for him.
WW
I like NESS and do a lot of business with him, but RG Machine does the same type bands and they are only $50 from him. All you need to tell him is the diameter of the tanks and the center to center spacing on the manifold you are using. Any tanks & any manifolds.
Heck he could do you a set for double spare air's if you asked him!
Dave D
A hundred dollars for bands? Why? I put mine together for less than $10 (not including the manifold). As for isolation, why bother? An isolation manifold is better if a burst disk or the tank neck o-ring blow. I've never heard of a tank neck o-ring blowing and I've never heard of a burst disk blowing on a dive. There's probably as much of a chance of an isolation valve failure.
The other question is why bother with small doubles? In days gone by, large tanks were hard to find, so doubling small tanks was the only option for lots of air. Doubles are slightly more comfortable and easier to dive than a single, but not enough to justify the extra $ and trouble.
The other question is why bother with small doubles? In days gone by, large tanks were hard to find, so doubling small tanks was the only option for lots of air. Doubles are slightly more comfortable and easier to dive than a single, but not enough to justify the extra $ and trouble.
You can make bands that will squarely align and hold a set of 104's for under $10? Have you any idea what kind of gold mine your sitting on?
I made one set up for a pair of slim 71.4's back in '89. I'm still using that set up. I've never made a set up for 104's, but I don't see why they should be any different except for size.
canuckdiver
Contributor
walter, how did you get the spacing accurate?
I can figure how to get the loops the right size, but nervous about putting a strain on the manifold.
I can figure how to get the loops the right size, but nervous about putting a strain on the manifold.
How fast can you shut down/isolate a isolator manifold? With any manifold doubles, you have to be able to shut off the correct post in time to preserve enough gas to surface safely, or it is useless. If you can't do it really fast in a freeflow situation, then the "safety" of double 40's will be more illusional than actual as by the time you have the correct post shut down, most/all the gas has escaped.
If you feel the need of the comfort of having redundancy double, but aren't in a overhead environemnt (hard or soft), I'd probably just sling an AL40 as a bailout bottle instead of getting tiny doubles.
If you feel the need of the comfort of having redundancy double, but aren't in a overhead environemnt (hard or soft), I'd probably just sling an AL40 as a bailout bottle instead of getting tiny doubles.
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