Worthington X7 HP 65

[Mndiv]

How does the capacity/volume of a Worthington X7 HP 65 compare with that of an AL80? I am thinking of buying a Worthington X7 HP 65 and have been using an AL80 up to now. I know its negatively buoyant but how does it compare in general?

Thanks so much for the info!

 

[whaylonsmithers]

Feet are feet regardless of the which tank you squash them into. The 65 is 81.25% of the 80, assuming you fill both to service pressure. I checked divegearexpress and they say Worthington X7 65cf is 25.1lb and buoyancy -8.7lb:-3.9lb Luxfer S80 weights 31.4lb and buoyancy is -1.4lb:+4.4lb.

So its 6lb lighter, 7-8lb less buoyant and has not quite as much air. You might trim a bit more head-down than you are used to and need less lead over all.

For me on a single tank and jacket BCD the difference is about the same as taking 6lb of trim weight off the tank when I go from Ally to Steel, which seems roughly to match up with the buoyancy differences of the tanks shown above.

 

[SubMariner]

How does the capacity/volume of a Worthington X7 HP 65 compare with that of an AL80? I am thinking of buying a Worthington X7 HP 65 and have been using an AL80 up to now. I know its negatively buoyant but how does it compare in general?

Thanks so much for the info!

Feet are feet regardless of the which tank you squash them into. The 65 is 81.25% of the 80, assuming you fill both to service pressure. I checked divegearexpress and they say Worthington X7 65cf is 25.1lb and buoyancy -8.7lb:-3.9lb Luxfer S80 weights 31.4lb and buoyancy is -1.4lb:+4.4lb.

So its 6lb lighter, 7-8lb less buoyant and has not quite as much air. You might trim a bit more head-down than you are used to and need less lead over all.

For me on a single tank and jacket BCD the difference is about the same as taking 6lb of trim weight off the tank when I go from Ally to Steel, which seems roughly to match up with the buoyancy differences of the tanks shown above.

You got all the "scientific" explanations, but I'd just like to give an opinion based on experience: go for a high pressure steel 80. Why? Because:

1) They hold more air than a 65: if you're already "using up" an 80, why would you want LESS air?
2) They are about the same height/diameter as an AL 60, so less cumbersome.
3) They are negatively buoyant so you need less weight on your belt or whatever weighting system you are using.

If you are a new diver & find you are using up your an AL 80 faster than you'd like, relax... the time WILL come when you do not feel like a Human Hoover. It just takes more dive experience to learn to relax & breath in & out a little slower and fuller. So if you are really keen on getting your own tank, a high pressure steel 80 would probably be a good investment.

However, if you are a more experienced diver & have always found that you use up an AL 80 a "little too fast", you may want to consider looking at high pressure 100 steel. They are approximately the same dimensions as an AL 80, but you will obviously get more air. And of course the weighting benefits of a steel tank.

FWIW,

 

[Scared Silly]

If you are diving an AL80 in cold water and are fine with the physical size of the cylinder I would suggest a HP100 as it is about the same size. Further, if you get a short fill say 3000psi instead of the full 3442 psi the cylinder will still contain 87 cuft which is still 10 cuft more than an AL80 which holds just over 77 cuft. The small HP cylinders like the 65 and 80 are for small divers.

 

[eelnoraa]

I consider myself a small diver, and I think even HP80 tank is too short, so I can't imagine HP65. If you dive bp/w, your wing most likely will be longer than HP80, and chances are you will pinch your wing. So I will also suggest HP100, LP85, LP80, LP77 type of tanks over HP80/HP65

 

[Mndiv]

Thanks so much everyone! That cleared that up, the reason I asked about the HP65 is that I found a local diver that was selling his HP65's for 90.00 each, which is of course a great deal compared to the over 325.00 new. As it is, I'll probably have to save up a little more, but I'll be sure to pass on the HP65. Thanks again everyone

Cheers

 

[whaylonsmithers]

Yeah, what they said Mndiv, but don't discount the 65. The price sounds right, especially if its in date. If you dive shallow and aren't huge on air consumption it could be for you - they're very easy to cart around. Have you tried asking this guy for a test dive? You might even get a dive buddy out of it.

 

[SubMariner]

I consider myself a small diver, and I think even HP80 tank is too short, so I can't imagine HP65. If you dive bp/w, your wing most likely will be longer than HP80, and chances are you will pinch your wing. So I will also suggest HP100, LP85, LP80, LP77 type of tanks over HP80/HP65

I am 5'4" and a steel HP 80 is by no means "too short". In fact, it's much more comfortable & less cumbersome than an AL80. The difference is especially noticeable if you ever happen to do a seated entry with the HP80 vs AL80.

Additionally, I have no problems with my dive rite set up & that tank.

 

[spectrum]

I can't overstate how short that cylinder is. When a LDS had one I thought it wasa freak. Be warned about getting trim to behave. it may also wreak havoc with cam band spacing and regulator elevation. The HP80 is a real nice upgrade from the AL80

 

[Graeme Tolton]

If you are diving an AL80 in cold water and are fine with the physical size of the cylinder I would suggest a HP100 as it is about the same size. Further, if you get a short fill say 3000psi instead of the full 3442 psi the cylinder will still contain 87 cuft which is still 10 cuft more than an AL80 which holds just over 77 cuft. The small HP cylinders like the 65 and 80 are for small divers.

+1
Better tank overall and you wont have to settle for selling it for $90 when you are done with it.