How delicate are manifolds?

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Sas

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I have a set of manifolded twin 12s that I've had for about a month. A few people have told me never to lift it by the manifold as it can damage it and a few more people have told me they've been lifting their twins by the manifold since the dawn of time with no issues. So given it is much easier to lift my tanks by the manifold, and I've only not been doing so as it is better to be safe than sorry, I'm wondering if the manifold does actually weaken if you use it as a handle?

As it would make my life easy :) But if it does damage the tank I'll stick to other methods of lifting...
 

Diver0001

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I don't lift mine by the manifold out of habit but I can't really see how it would cause big problems. I guess theoretically you could loosen it or wear the o-rings with slight turning to the point where it leaks (which is why I don't lift mine by the manifold). But I think you would have to hit it with a sledgehammer to actually break it.

R..
 

DA Aquamaster

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I am one of the "since the dawn of time guys", altouigh in polite company to avoid having ti explain it or argue it, I will lift by the knobs, not the isolator bar. It is one of those things that is so ingrained in diver culture that no one really thinks about it, but everyone thinks they are self proclaimed expert on it becasue they have heard it so often.

What really matters is that the bands are absolutely tight. Loose bands lead to bent isolators, and then not so much by lifting but by the slide hammer effect that occurs if there are any sudden stops with the tanks not perfectly level.

For example lets say a diver lifts the tanks out of the back of a pickup and sets them down on the concrete driveway slightly hard with oine tank contacting first. If the bands are loose the other tank (weighing-30-50 pounds depending on what tank and how full it is) will want to keep moving after the other tank has been stopped. If there is much veloity at all involved, it amounts to a lot of kinetic energy that must either be transferred by the bands to the motionless tank in contact with the ground or absorbed by the isolator. If the bands are loose and allow any skippage, that energy will be absorbebby the isolator and that will most likely bend it.

In this scenario, it does not matter whether the tanks were lifted by the knobs or by the isolator, but the "experts" will insist the damage was caused by the diver lifting it by the isolator whether they did that or not.

Personally, when I look at the construction of the valve knobs and the short but small diameter valve stem that secures the knobs, it becomes obvious that it must endure a great deal of the lifting forces when you use the knobs and that strikes me as being just as bad or worse than lifting by the isolator. There is clearance between knob and valve, so the stem either has to take all the load or flex slightly to share the load with the valve body.

The isolator bar itself is much better able to handle those routine lifting loads.
 

Sas

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I am one of the "since the dawn of time guys", altouigh in polite company to avoid having ti explain it or argue it, I will lift by the knobs, not the isolator bar. It is one of those things that is so ingrained in diver culture that no one really thinks about it, but everyone thinks they are self proclaimed expert on it becasue they have heard it so often.

That was the sense I was getting...

What really matters is that the bands are absolutely tight.

Yep.

The isolator bar itself is much better able to handle those routine lifting loads.

Fair enough, your example makes a lot of sense.
 

Texfrazer

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I got blasted one day by an LDS for lifting a pair of my 104's with the bar. I wish I had DA's answer handy. Good nerd (no offense intended!) talk usually helps calm these types of situations.
 

elan

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I wish I had that power to lift those at least 90lb of wight with one hand. :) If you do not lift them by one hand I cannot see how you can lift your tanks by the manifold. If you hold them inside then you take them by the valves unless you put the hands really really narrow. I personally find holding them by the outside of the valve much more comfortable as my hands are placed wider and I can use the muscles of the back as well as the biceps's instead of using just biceps when the hands are placed narrow.
 

Sas

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I wish I had that power to lift those at least 90lb of wight with one hand. :) If you do not lift them by one hand I cannot see how you can lift your tanks by the manifold. If you hold them inside then you take them by the valves unless you put the hands really really narrow. I personally find holding them by the outside of the valve much more comfortable as my hands are placed wider and I can use the muscles of the back as well as the biceps's instead of using just biceps when the hands are placed narrow.

Thanks for that but it's not really the question :wink: I find it easier to lift via manifold.
 

TSandM

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I was also told not to lift tanks by the manifold. Then I went down to Mexico and watched people do nothing but. If the ZG guys get away with lifting tanks by the manifold day after day, I figure it can't hurt much. Of course, those ARE Halcyon manifolds :)
 

Cave Diver

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I have a set of manifolded twin 12s that I've had for about a month. A few people have told me never to lift it by the manifold as it can damage it and a few more people have told me they've been lifting their twins by the manifold since the dawn of time with no issues. So given it is much easier to lift my tanks by the manifold, and I've only not been doing so as it is better to be safe than sorry, I'm wondering if the manifold does actually weaken if you use it as a handle?

As it would make my life easy :) But if it does damage the tank I'll stick to other methods of lifting...

Based on some of the abuse mine have taken, no where near as delicate as some would have you believe. HID's on the other hand...

And mine are NOT Halcyon. :wink:
 
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