Closed 100 Cubic Foot Luxfer Aluminum Tanks

[Lostdiver71]

100 Cubic Foot Luxfer Aluminum Tanks, previously O2 clean, need Hydro, 2.8 lbs positively buoyant when empty. $140 each or $260 for both, sells new at Divers Supply for $276.95 each. My wife says that I have too many tanks! Local pickup near Jupiter, FL.

 

[Lostdiver71]

 

[soonerwink]

negatively buoyant when empty

I think you are wrong on this, I used to have a Luxfer and Catalina AL 100 and both were positive buoyant when empty and at 500 psi even.

 

[SCUBAwithMitch]

 

[phoque]

That's an error. 100 cuft of air should weigh around 8 lbs or so, and it is not possible for the tank to be 4.6 negative when full and 2.8 negative when empty.
@soonerwink is correct. It most likely should read "positively buoyant 2.8 lbs when empty".

 

[Lostdiver71]

I checked and you are correct, they are 2.8 positive when empty. Post corrected!

 

[soonerwink]

View attachment 573791

The Catalina 100 cu ft (13.2 liter) cylinder has an 8" (20.3cm) diameter weighs 42 lbs. (19.1 kg) when empty is 26.5" (67.3cm) tall without the valve and its buoyancy when full is -5.2 lbs. (-3.54 kg). The cylinder becomes positive retaining a 2.2 lb. (1 kg) buoyancy characteristic when completely empty.

From owning and diving both, they are very similar. I think the Luxfer may have even been more buoyant than the Catalina. I wore the same amount of weight with both.