Need two LP95's

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I am learning a lot here, keep up the information flow.. But who is Ron?
 
HP80 is heavier than LP72s or AL80s, they are supposedly -9# full and -3# empty. I looked into them once because I have a buddy who has a set and they looked like really good alternatives.

They are at least -3# empty, I thought -5# but thats not enough to argue. I doubled them up for a lady that was 4'10" back when they really started to pop on the market about 10 years ago. She couldnt sling double 95's. She loved them and still uses them today for cave diving. They call them Super 80's. I understand the theory on SAC rates and how different types of diving and work load effect it. I have been diving with a single LP 95 for a couple of years since I sold my doubles. I usually fill them to around 3500 psi Which I know is 1100 psi more than they are rated for but that gives me about 120 cuft of gas or so. If I went to the double 80's it would only give me about 40 more cubic feet. I want to make them side mounts because I am more concerned with streamlining rite now.
 
I was just going off the specs listed at X-Series Steel SCUBA Tanks by Worthington Cylinders - Dive Gear Express , I'm not sure how accurate that information is... I'm guessing it was provided by the manufacturer though?

I don't know that sidemount would better your streamlining compared to a single backmount tank. I couldn't even tell a difference in streamlining after moving from a set of doubles backmounted. Course, I went to sidemount for very different reasons.
 
I think HP80s might be a little on the light side. What type of diving do you plan on doing? And how good is your SAC rate? Keep in mind that different environments affect SAC and it might not be what you think in a different environment.

I thought we were talking about cave diving (which i do) I would look awful stupid diving the Black Bart with side mounts huh!. My sac rate is somewhere between 8 to 11 psi min unless there is a lot of flow.
 
HP80 is heavier than LP72s or AL80s, they are supposedly -9# full and -3# empty. I looked into them once because I have a buddy who has a set and they looked like really good alternatives.

You're right...and that surprises me (not that you're right, but that they are so negative). I still don't think it's enough gas, though.

kalik:
I thought we were talking about cave diving (which i do) I would look awful stupid diving the Black Bart with side mounts huh!. My sac rate is somewhere between 8 to 11 psi min unless there is a lot of flow.

I wasn't sure because I don't see anything about cave diving in your profile. Personally, I dive sidemount 95% of the time. The other 5% I'm teaching. I'd even dive a single sidemount on the Black Bart. It's just more comfortable for me and I'd rather have the bottle where I can see it. In what size tank is that your SAC? In 95s?
 
Same amount of gas as AL80s or LP72s(overfilled to 2700), but with better bouyancy characteristics. Smaller capacity tanks have their place, I wouldn't use them for every occassion though.

I'd say LP85s/HP100s would be a much better choice still, but if he already has them lying around, I'd rock them. The HP80s are still super stubby, which could make them easier to manipulate if you're a midget.

My sac rate is somewhere between 8 to 11 psi min unless there is a lot of flow.

That only compares to similar tank sizes tanks.

Try this link, http://www.spearfishing.org/bruces_tips/java/sac.html it'll give you a universally acceptable measure of your SAC rate.
 
Understood Mat. that SAC is for my single 95 that I have been diving. But i am going to have to disagree on this point. It doesnt matter what size tank that I am breathing from or even if I am on a hookah rig. What matters is how much gas I breathe or psi per minute. The only other factor should be depth. The way I calculate SAC is air consumption over time divided by depth plus 33 over33. This is always comparable to other factors as current, work load and whether I have a hangover or not. I think what you are talking about is more about dissimilar tank theory than just plain SAC. K
 
I wasn't sure because I don't see anything about cave diving in your profile. Personally, I dive sidemount 95% of the time. The other 5% I'm teaching. I'd even dive a single sidemount on the Black Bart. It's just more comfortable for me and I'd rather have the bottle where I can see it. In what size tank is that your SAC? In 95s?

I didnt put alot of things on my profile because I enjoy all aspects of diving. As far as enough gas in the tank I look at it as if me and my buddy are satisfied with getting as far as we can on what we got then good enough for me. I could be wrong but I always thought that the horse collar and the double hose reg were the greatest thing in the world. I could be wrong. K
 
Understood Mat. that SAC is for my single 95 that I have been diving. But i am going to have to disagree on this point. It doesnt matter what size tank that I am breathing from or even if I am on a hookah rig. What matters is how much gas I breathe or psi per minute. The only other factor should be depth. The way I calculate SAC is air consumption over time divided by depth plus 33 over33. This is always comparable to other factors as current, work load and whether I have a hangover or not. I think what you are talking about is more about dissimilar tank theory than just plain SAC. K

"psi per minute"

Thats going to be at different rates on different sized tanks.

100psi from a LP72 isn't the same as 100psi from a LP108. It'll take you longer to breath 100psi from a LP108 than it would from a LP72, since the volume's are so much greater.

Even with similar contributing factors(current, work load, hangover), you'll get a different measurement that won't compare to the same dive on a different tank due to the variability of the "psi per minute" from those dissimilar tanks.

100psi = 3.6cfm on a LP95
100psi = 2.9cfm on a LP72
100psi = 2.3cfm on a HP80

Using your formulae, the SAC rate won't relate to other cylinder volumes. If you use cubic/feet per minute to describe your SAC, its universal.
 
I see your point. but I think that we are arriving at 2 different solutions. I was just saying how many psi I breathe per minute. I believe that you are calculating how long tanks of different sizes will last by calculating cu ft per minute. I do admit I could have been a little clearer in my intention.
 
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