DirtRider
Contributor
I'm 6'2" and 210lbs. Pleaty strong to carry whatever weight of tank. Currently have 2 AL80s. A bit of an air hog - about a .85-.9 SAC rate if I average my dives according to my suunto vytec software. Live in Chicago so mostly cold fresh water diving in the Great Lakes. One of the few wetsuit divers. Drysuit will probably come along eventually.
I've only been diving a year and only have 35 dives. I got the bow, aow, wreck, deep, and nitrox certs though that doesn't mean much. I have done a few dives with some pretty serious tech dives up here who are also full tdi instructors and they said they were very impressed with my dive skills already during our 100'-130' dives. I also feel very comfortable but know that there is no substitute for experience. I'm going to pursue tech diving training and want to start accumulating and getting used to some of the gear. I have a zeagle ranger bcd which I should at least be able to start out on doubles with. Mares abyss regulators. Tanks are an obvious necessary upgrade.
Even after reading many threads I am still confused about LP, HP and the + rating. If for example the LP tanks are considered full at 2400 and have a + for 10% overfill to bring them to 2640 yet only reach the rated capacity at that extra 10% then what is the point of having a plus rating? This seems like some bogus marketing scam yet I'm sure that isn't the case. Do that many LP cylinders actually fail the hydro +10% portion?
When considering dimensions of the tank and selecting an HP and LP tank of the same physical size, if an HP tank filled to the lower pressure of an LP tank still yields the same amount of cu ft of air yet has the option of yielding more when a better fill is available, why would anyone ever buy an LP?
What is the physical design difference between an LP and HP tank? Are the HPs actually made of notably thicker steel or something?
This may be a stupid question but HP tanks seem to be 7.25" instead of 8" like LP for many sizes. Can anyone notice a drag difference even though we move so slowly? In hydrodynamics a longer vessel of same width is more streamlined. Adding width and reducing length is a double wammy. I only ask because I was on one dive this summer where the current was so strong that my buddy and I were the only ones on the charter who could make it from the swim line to the anchor line even though it was only about 15'. Everyone else drifted off so I have learned the value of being streamlined (and being young and in shape). This is also one of the reasons I like diving in wetsuits.
Are the galvanized or coating differences major factors?
Anything else to watch out for in buying steel tanks or manifolds?
I think buying doubles and a manifold is my best bet for now. I can still use just one of the tanks for extended nitrox dives and for having more air for a safety margin. Then I can add the additional tank when pursuing my adv nitrox/decomp training. It is just a matter of figuring out which tanks to buy.
I've only been diving a year and only have 35 dives. I got the bow, aow, wreck, deep, and nitrox certs though that doesn't mean much. I have done a few dives with some pretty serious tech dives up here who are also full tdi instructors and they said they were very impressed with my dive skills already during our 100'-130' dives. I also feel very comfortable but know that there is no substitute for experience. I'm going to pursue tech diving training and want to start accumulating and getting used to some of the gear. I have a zeagle ranger bcd which I should at least be able to start out on doubles with. Mares abyss regulators. Tanks are an obvious necessary upgrade.
Even after reading many threads I am still confused about LP, HP and the + rating. If for example the LP tanks are considered full at 2400 and have a + for 10% overfill to bring them to 2640 yet only reach the rated capacity at that extra 10% then what is the point of having a plus rating? This seems like some bogus marketing scam yet I'm sure that isn't the case. Do that many LP cylinders actually fail the hydro +10% portion?
When considering dimensions of the tank and selecting an HP and LP tank of the same physical size, if an HP tank filled to the lower pressure of an LP tank still yields the same amount of cu ft of air yet has the option of yielding more when a better fill is available, why would anyone ever buy an LP?
What is the physical design difference between an LP and HP tank? Are the HPs actually made of notably thicker steel or something?
This may be a stupid question but HP tanks seem to be 7.25" instead of 8" like LP for many sizes. Can anyone notice a drag difference even though we move so slowly? In hydrodynamics a longer vessel of same width is more streamlined. Adding width and reducing length is a double wammy. I only ask because I was on one dive this summer where the current was so strong that my buddy and I were the only ones on the charter who could make it from the swim line to the anchor line even though it was only about 15'. Everyone else drifted off so I have learned the value of being streamlined (and being young and in shape). This is also one of the reasons I like diving in wetsuits.
Are the galvanized or coating differences major factors?
Anything else to watch out for in buying steel tanks or manifolds?
I think buying doubles and a manifold is my best bet for now. I can still use just one of the tanks for extended nitrox dives and for having more air for a safety margin. Then I can add the additional tank when pursuing my adv nitrox/decomp training. It is just a matter of figuring out which tanks to buy.