Double AL80s

[Kronek]

Hey SB, question about viability of doubles.

My main tanks right now are a set of old PST Steel 100s manifolded up. My backup tanks are 2 PST Steel 80s. I am having a hell of a time finding a manifold for the 80s however due to the smaller tank neck diameter.

I have 2 AL80's with a 3/4" neck, how much extra weight do you all think I would need to make up the difference if I banded and manifolded my AL80s over the steel 100s? These would just be used for shore dives when I cant make it into get a fill before a charter or other important dive. AKA, not that often.

I'm diving a steel backplate, 6mm Neoprene suit and 100 to 300gm undergarments. My normal winter setup is 100s, steel plate + 300gm undergarment and I needed 18lb. With my summer thermals I can get away with 6lb.

My math says about 20 pounds of lead needed for switching to double 80s for the end of the dive. I know I could just band them up and run them as independant, which is what I am going to do next weekend. But I wanted to start mulling things over before then.

 

[bumcikaz]

5-6lbs add for each tank, so +10-12lbs

 

[rx7diver]

My main tanks right now are a set of old PST Steel 100s manifolded up. My backup tanks are 2 PST Steel 80s. I am having a hell of a time finding a manifold for the 80s however due to the smaller tank neck diameter.

Kronek,

Are you thinking to buy a used manifold? (Are these the 3,500 psig PST HP 80's?) Do you need bands, too?

And are you aware that (1) these double PST HP 80's will require less weight than your double PST HP 100's, (2) the wings that you use with the 100's might not work well with the HP 80's (the wing might be too long), (3) some divers find the buoyancy characteristics of the double HP 80's won't work for them, and (4) the double HP 80's can be a PITA to dress into/out of (because they're so short)?

Safe Diving,

rx7diver

 

[Kronek]

rx7, sent you a messaged.

I was thinking about using my AL80s as my second doubles and loaning out my HP Steel 80s. Because as you said, they are way too short to put on. The plan would be to eventually buy 2 more HP100s and a manifold and have 2 sets of 100s. But until then, I might as well have a second semi good set of doubles.

 

[rx7diver]

Ah, okay. I misunderstood that you were reluctantly considering the double Al 80's, that you preferred double HP 80's.

Just replied to your PM.

---------- Post added August 4th, 2013 at 05:56 PM ----------

Just found the old thread. This is the link to the end of it. Read the earlier posts in the thread to get the details. http://www.scubaboard.com/forums/tanks-valves-bands/345678-older-steel-tanks-3.html#post5438140.

---------- Post added August 4th, 2013 at 05:57 PM ----------

Oops, meant to post this in a reply to your PM. Will do that now.