Matt S.
Contributor
Sorry in advance for rambling on here...
I am a new (new!) diver, and have only done cold, rainy, Seattle drysuit dives so far. I learned how to do a weight check in my OW class of course--and I did class in my drysuit and personal gear--and I ended up needing about 40 lbs. (My gear and specs at the very end.)
Diving on my own, with rental tanks, I check the tank specs and adjust weight as needed. But now I think I may have been overweighted from the beginning. Here's why.
On my last dive, I rented a new kind of tank, and adjusted my weight accordingly. I was told it was a particular kind of Faber HP 80, which is about -13 lbs when full. So, the way it worked out, I needed to drop 8 lbs of lead from my last config. But when I got in the water, I had to kick a bit to get down. I must have had the wrong tank specs, because on my last dives, I sunk easily when I deflated my BCD. This time I was clearly under weight compared to last time. (but, the dive went OK and I didn't go Polaris at the end. I also felt pretty agile under water, compared to before.)
This long preamble is just so I can ask this: when properly weighted, how hard do you have to work to get down that first 5 or so feet? Or is deflating the BCD like hitting the elevator down button? I'll do another weight check, but it would help to know how it should feel at the beginning of a dive with a full tank.
It seems like you should be negative at the beginning of your dive by the weight of the air that you will consume--5 or more pounds--and being that negative ought to make you sink pretty easily.
I would rather be a few pounds over than under, but at the same time, now I am wondering if I am carrying an extra 8-10 lbs that I don't need.
(As an aside, I am surprised that dive shops don't mark the buoyancy specs on the tanks, or at least post the data somewhere. It's important information! And sometimes it is hard to tell the make of tank from the markings.)
I am a new (new!) diver, and have only done cold, rainy, Seattle drysuit dives so far. I learned how to do a weight check in my OW class of course--and I did class in my drysuit and personal gear--and I ended up needing about 40 lbs. (My gear and specs at the very end.)
Diving on my own, with rental tanks, I check the tank specs and adjust weight as needed. But now I think I may have been overweighted from the beginning. Here's why.
On my last dive, I rented a new kind of tank, and adjusted my weight accordingly. I was told it was a particular kind of Faber HP 80, which is about -13 lbs when full. So, the way it worked out, I needed to drop 8 lbs of lead from my last config. But when I got in the water, I had to kick a bit to get down. I must have had the wrong tank specs, because on my last dives, I sunk easily when I deflated my BCD. This time I was clearly under weight compared to last time. (but, the dive went OK and I didn't go Polaris at the end. I also felt pretty agile under water, compared to before.)
This long preamble is just so I can ask this: when properly weighted, how hard do you have to work to get down that first 5 or so feet? Or is deflating the BCD like hitting the elevator down button? I'll do another weight check, but it would help to know how it should feel at the beginning of a dive with a full tank.
It seems like you should be negative at the beginning of your dive by the weight of the air that you will consume--5 or more pounds--and being that negative ought to make you sink pretty easily.
I would rather be a few pounds over than under, but at the same time, now I am wondering if I am carrying an extra 8-10 lbs that I don't need.
(As an aside, I am surprised that dive shops don't mark the buoyancy specs on the tanks, or at least post the data somewhere. It's important information! And sometimes it is hard to tell the make of tank from the markings.)