Dashrynn
Contributor
im not fighting just having fun and poking fun
redundant air at less than 30'?
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DaleC
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Why does the visibility matter? Sure zero vis is a PITA, but 10 foot?
Dashrynn
Contributor
just a backup in case something goes bad i.e caught in fishing net, just gives me time to sort issues out if they arise and the air is needed. 10 ft of viz is just an example of viz, on a good day at the local spot 15 ft is beautiful. Or the local spot has a ferry that runs right on the other side of the reef, what if i get swept into that lane and i need more time to get back but cant surface but i use more air than desired from excessive work? or if i somehow magically become lost? Just a safety for human error.
oh and hey i have to admit i look pretty b/a with a pony slung...almost like a tech diver doesn't really matter but it makes me feel like a navy diver rawr
Oh and my words are normally confused so beware.
DaleC
Contributor
No worries about your words Dashrynn 
Are you in Wash DC or Wash the state? If the state is the spot with the ferry Edmonds or Keystone (Port Townsend/Fort Casey)? If so we are not that far apart and our group usually goes down every fortnight or so.
It's no critcism of your choice and you dive in a way that feels comfortable but I did not use a pony for that reason (extra time to solve problems). I calculate the gas I need to safely ascend from whatever depth I am diving and, because I am soloing, add some more for solving problems. This is called my rock bottom reserve and it would be carried in my back gas. The pony was for a catastrophic failure of my back gas.
Here's an example:
Depth 100fsw with a stressed surface air consumption rate of 1cuft/min.
5 min. to solve problem at depth = 20cuft.
Ascent rate of 60ft/min. averaged = 4.5cuft.
3 min. SS at 15ft. = 6cuft.
Total = 30.5cuft.
With an Al80 1200psi = 30.8cuft. so 1200psi was my rock bottom pressure for 100ft.
That was when I would begin my ascent, not when I would surface necessarily. For example I could ascend to 60fsw and assume a new rock bottom reserve value:
60fsw with a stressed SAC of 1cuft./min.
5min. to solve problem at depth = 15cuft.
ascent rate of 60ft/min. = 2.5cuft.
3 min. SS at 15ft. = 6cuft.
Total = 23.5cuft.
With an Al80 900psi = 23.1cuft. so I could hang out at 60ft till then.
At 30fsw using the same formula my rock bottom would = between 650 and 700psi.
I will edit in two links for calculating rock bottoms in a second if you are interested. Reading and understanding this really helped me:
Lamonts rock bottom page http://www.scriptkiddie.org/diving/rockbottom.html
NWGD (Bob)'s gas management article http://www.nwgratefuldiver.com/articles/gas.html
Are you in Wash DC or Wash the state? If the state is the spot with the ferry Edmonds or Keystone (Port Townsend/Fort Casey)? If so we are not that far apart and our group usually goes down every fortnight or so.
It's no critcism of your choice and you dive in a way that feels comfortable but I did not use a pony for that reason (extra time to solve problems). I calculate the gas I need to safely ascend from whatever depth I am diving and, because I am soloing, add some more for solving problems. This is called my rock bottom reserve and it would be carried in my back gas. The pony was for a catastrophic failure of my back gas.
Here's an example:
Depth 100fsw with a stressed surface air consumption rate of 1cuft/min.
5 min. to solve problem at depth = 20cuft.
Ascent rate of 60ft/min. averaged = 4.5cuft.
3 min. SS at 15ft. = 6cuft.
Total = 30.5cuft.
With an Al80 1200psi = 30.8cuft. so 1200psi was my rock bottom pressure for 100ft.
That was when I would begin my ascent, not when I would surface necessarily. For example I could ascend to 60fsw and assume a new rock bottom reserve value:
60fsw with a stressed SAC of 1cuft./min.
5min. to solve problem at depth = 15cuft.
ascent rate of 60ft/min. = 2.5cuft.
3 min. SS at 15ft. = 6cuft.
Total = 23.5cuft.
With an Al80 900psi = 23.1cuft. so I could hang out at 60ft till then.
At 30fsw using the same formula my rock bottom would = between 650 and 700psi.
I will edit in two links for calculating rock bottoms in a second if you are interested. Reading and understanding this really helped me:
Lamonts rock bottom page http://www.scriptkiddie.org/diving/rockbottom.html
NWGD (Bob)'s gas management article http://www.nwgratefuldiver.com/articles/gas.html
Dashrynn
Contributor
Hey bobs and lamonts information being used here who woulda thunk it? guess this world is smaller than i thought. Yes i am quite familar with gas management, EVERY solo dive i do, i come back with 1000 psi in my hp100. I know exactly when to turn around and i have a set way of doing things. to me all of this is common sense, to some not so but hey im not good in everything. I never do deep dives with an al80 i have 2 and there used for shallow 50 fsw dives.
I never suck air out of my pony, that thing is for emergency use only, just to clarify.
Keystone is my back yard, i dive that spot more than i dive any other. In fact half of my dives are at keystone.
oh yeah i got off track, anyways i dive a pony all the time when solo and sometimes with people. but at around 15 20 fsw i see no point. but after 30 your supposed to do a safety stop so i can skip it but i'd rather not. I look at it like this, my pony is my dive buddy, if i don't have it, i feel paranoid. It just depends on where im diving, but i prefer my pony. Hell i have it and im paying for the reg to be serviced so why not? im a cautious diver, paranoid, but i stay alive without incident and thats how i want it to stay.
I never suck air out of my pony, that thing is for emergency use only, just to clarify.
Keystone is my back yard, i dive that spot more than i dive any other. In fact half of my dives are at keystone.
oh yeah i got off track, anyways i dive a pony all the time when solo and sometimes with people. but at around 15 20 fsw i see no point. but after 30 your supposed to do a safety stop so i can skip it but i'd rather not. I look at it like this, my pony is my dive buddy, if i don't have it, i feel paranoid. It just depends on where im diving, but i prefer my pony. Hell i have it and im paying for the reg to be serviced so why not? im a cautious diver, paranoid, but i stay alive without incident and thats how i want it to stay.
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No worries about your words Dashrynn
Are you in Wash DC or Wash the state? If the state is the spot with the ferry Edmonds or Keystone (Port Townsend/Fort Casey)? If so we are not that far apart and our group usually goes down every fortnight or so.
Curtis (Dashrynn) is out here, Dale ... I've dived with him. He's a very nice young man and a pretty darn good diver. I believe he's stationed out at Whidbey Island Naval Air Station (correct me if I'm wrong on that one, Curtis) ... so he's probably talking about Keystone ...
... Bob (Grateful Diver)
R
redacted
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Perhaps the biggest effect would be that he would not have to start blowing bubbles as quickly as he ascends since the gas in the lungs would have more room to expand.
DaleC
Contributor
Hi Curtis (and Bob), I'll try to remember to link you in the next time we plan to go down there; perhaps we can say hello in the parking lot sometime. Our club is talking about a camp and dive at Fort Casey this summer (don't know when just yet).
Oh well about the gas calculations then, I was in a mood to type anyways :shocked2:. I always think that along with the few people participating in the thread there are many just reading along so maybe it will be of value to one of them.
Also again, dive the way that works for you and don't take what I say as a critcism. I may discuss the pros and cons of different strategies because I like to think about things but in real life I have many buddies who dive different rigs and we all get along just fine. I myself dive independant doubles and sometimes take flack for that (poopy heads).
Best regards,
Dale.
Oh well about the gas calculations then, I was in a mood to type anyways :shocked2:. I always think that along with the few people participating in the thread there are many just reading along so maybe it will be of value to one of them.
Also again, dive the way that works for you and don't take what I say as a critcism. I may discuss the pros and cons of different strategies because I like to think about things but in real life I have many buddies who dive different rigs and we all get along just fine. I myself dive independant doubles and sometimes take flack for that (poopy heads).
Best regards,
Dale.
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