Why don't more people use compact AL100s?

[scubafanatic]

...a detail that's all to often overlooked isn't the question of .......'what's your favorite tank ?', it's the question of..... 'what's your favorite tank that's most likely to be available at your chosen dive site ?'

 

[ptyx]

...a detail that's all to often overlooked isn't the question of .......'what's your favorite tank ?', it's the question of..... 'what's your favorite tank that's most likely to be available at your chosen dive site ?'

For people having their own tank farm in the garage, it's 'what's your favorite tank with your usual exposure protection'.

I love my HP100/130 for dry suit California diving. I tried the HP100 once with a shorty in a (fresh water) pool - worst tank ever, I could barely stay afloat.

 

[scubafanatic]

For people having their own tank farm in the garage, it's 'what's your favorite tank with your usual exposure protection'.

I love my HP100/130 for dry suit California diving. I tried the HP100 once with a shorty in a (fresh water) pool - worst tank ever, I could barely stay afloat.

or, what is the max fill pressure at the onsite fill station ?

my tank farm is modest...... 10 'singles'..... 2 twinsets.

 

[cool_hardware52]

Aluminum makes poor ballast at ~165 lbs / cuft.

Steel by comparison is ~490 lbs / cuft.

Tobin

 

[Scott L]

I love my HP100/130 for dry suit California diving. I tried the HP100 once with a shorty in a (fresh water) pool - worst tank ever, I could barely stay afloat.

Isn't that the purpose of a wing?

 

[cool_hardware52]

Isn't that the purpose of a wing?

Not really.

Divers use BC's to compensate for the change in buoyancy of their exposure suit WRT to depth.

Component selection, tank(s) backplates, etc. should be selected based on the total ballast required.

Total ballast required is (mostly) a function of the buoyancy of the diver's exposure suit.

The correct solution to being over weighted is never a larger BC.

Tobin

 

[Scott L]

An X8-130hp is -11.7lbs bouyant filled. A X7100hp is -10.0lbs bouyant filled. A fit diver will not be "floaty" at the surface in either. No?

 

[fdog]

An X8-130hp is -11.7lbs bouyant filled. A X7100hp is -10.0lbs bouyant filled. A fit diver will not be "floaty" at the surface in either. No?

Meh. Well, I guess that depends on what you'd consider a "floaty" tank, eh? For myself and the folks I usually dive with, the term "floaty" is used for a cylinder that becomes positively buoyant when empty.

So at roughly -2.5 lbs each, both HP130's and HP100's certainly wouldn't be floaty when empty. Actually, I consider HP130's to dive pretty much identically to HP100's; I change nothing in my setup when switching between them, and never really notice a difference when underwater (except longer bottom times!).

Al80's become floaty. Just like Al40's, which we consider "Aluminum bouquets" at the end of long dives.

IIRC, when I've dove Al100's they turned positive at the end of the dive, so these would be "floaty" too, by how we refer to them.

Diving a balanced rig is important to me, so I'd be making cylinder selections based on end-of-dive weighting. If I was negative, at the surface with an (empty) steel cylinder and no lead, I'd be switching to an Aluminum cylinder that was floaty.


All the best, James

 

[Scott L]

Actually, I consider HP130's to dive pretty much identically to HP100's; I change nothing in my setup when switching between them, and never really notice a difference when underwater (except longer bottom times!).

This was the point I was trying to make. As usual, your version is much superior.

 

[fdog]

Weeeelll...not superior, but certainly more wordy! Hat's off to your brevity.


All the best, James