Buoyancy Question

[ccx2]

Thank you all for taking the time to try and help me out with this. I know i asked for a formula and i thought there would be a simple one ,but the first posters that responded took it into a bunch of math about volume and so forth that i couldnt understand and it got me very frustrated,but thank you so much for trying to help.
Charlie99 explained it to me best where i could somewhat understand it,Thank you again.
Ive spent a lot of money on all this gear and am going to Mexico again in a couple of weeks and wanted to be prepared for about four days of diving but now am very frustrated and seriously yhinking of leaving it all at home and selling it when i get back.
I am very comfortable with my skills that ive learned and feel that i do very well diving, and if left to dive square profiles ,buy the book dives, i would be fine and have no problems. But in the real world i find that everyone dives with a computer, and from my exsp when diving in mexico there is a Divemaster and you are expected to dive with him,and i want that because i am a newbie and like someone helping/guiding me thru the dive, but they are diving a computer and i dont want to play follow the leader if i have no computer.
And this brings me to my dilema, my wife bought me a Mares Puck computer and i cant figure out how to use it, im not a computer guy and cant even figure out how to download or upload or whatever you call it to watch the instruction video on the computer . I tried to figure it out by reading the manual but you have to press this damn button in a certain sequence to get it to do anything in one mode and its got a bazzillion different modes to do this function and that, no way i will remember all that while trying to enjoy a dive, i cant even remember it sitting in the recliner . And then if i did remember it long enough to use it in mexico it will be months before i would use it again and would have to relearn it.
I think i will be selling the whole works soon and going back to freediving but i sure will miss scuba diving.
Where is a good place to show my gear for sale,anyone have a suggestion. Thanks.

 

[TSandM]

ccx2, is there a dive shop near you? Why don't you see if you can get a DM to sit down and take you through the basic menus on your computer? Or take the E-diving class for the Puck. In reality, you don't have to use many functions on a computer, especially if you are simply diving air. You have to know what the alarms mean, and what the violation screen looks like. But the rest of the time, the computer just shows you depth and time, and remaining no deco time. They are really pretty simple instruments, and many of them have a lot of functionality you may never use.

I am sorry if the math was too much. A kind of simple rule of thumb is that, for someone between 100 and 150 pounds, add five pounds in salt water; above 150 pounds, add six; above 250, add seven. Fine tune in the water, using the weighting procedure you were taught in your open water class.

If you do the weight check with a full Al80 tank, add six pounds.

Does that make it any more palatable? Diving isn't that complicated, but having a little grasp of arithmetic does make some things easier.

 

[ccx2]

ccx2, is there a dive shop near you? Why don't you see if you can get a DM to sit down and take you through the basic menus on your computer? Or take the E-diving class for the Puck. In reality, you don't have to use many functions on a computer, especially if you are simply diving air. You have to know what the alarms mean, and what the violation screen looks like. But the rest of the time, the computer just shows you depth and time, and remaining no deco time. They are really pretty simple instruments, and many of them have a lot of functionality you may never use.

I am sorry if the math was too much. A kind of simple rule of thumb is that, for someone between 100 and 150 pounds, add five pounds in salt water; above 150 pounds, add six; above 250, add seven. Fine tune in the water, using the weighting procedure you were taught in your open water class.

If you do the weight check with a full Al80 tank, add six pounds.

Does that make it any more palatable? Diving isn't that complicated, but having a little grasp of arithmetic does make some things easier.

Thanks for the encouraging word, i guess i kinda fell into the depths with my reply. I actually figured out how to get the course up on the computer a minute ago but its late and i will try to go into it and learn it tomorrow. Im really trying to cram all this info in the next week and have gotten very frustrated and am starting to rethink if im smart enough to learn it , i will press on. Thank you.

 

[rivers]

ccx2, the best way to figure out how much weight you need for mexico is to do a shore dive and weight check when you get there. Where are you going in Mexico? If it's Cozumel, I know a couple of places where you can rent a tank and weights (as well as find a buddy), and have a nice, benign dive as well as check your weight.

 

[Nitro91]

usually i use 14 lbs with a 5/4mm and dss bcd 6lb plate
but i used a steelie the last dive and used 3 lbs lol, no idea how that much weight can be dropped

 

[ColoDale]

I generally use 14-16 lbs in Cozumel. With that weight, I use a 3mm full jacket, back inflate BCD which has maybe 3-5 pumps of air in it at the bottom at the beginning of the dive, 5 mm (new) booties, surf shorts, no camera. 4 lbs on my back and the rest in a neoprene weight belt (a bit of bouyancy).

I generally keep my weighting very fine tuned but if I know I will be finning alot or have more work, I will add 2 lbs. I used more weight in general when I started diving.

I am 6'7" and 260 lbs.

This is my benchmark for Cozumel Mexico and I don't know your weight so use this for what it's worth. Don't feel bashful about telling the DMs when there about weighting - they'll help. If not, change DMs/dive op - it's your dive not theirs.

 

[beanojones]

PADI does have a pretty simple rule of thumb that works pretty well:

With your BCD empty, and holding a full breath, you should float at eye level. With this amount of weight, all you need to start descending is to exhale. It's not exact, but it does get you in the ballpark. It's easy enough to check right off a boat as well. You do need to get your legs still for it to work right though.

Waving your arms to descend will almost always not work as well as you think it might, because almost everyone inhales and does a some version of a valsalva maneuver when they are trying hard to do something.

In general, weighting so a gentle exhale starts your descent is the way to go, for a number of reasons, and PADI's standard buoyancy check addresses that.

 

[Blue Sparkle]

PADI does have a pretty simple rule of thumb that works pretty well:

With your BCD empty, and holding a full breath, you should float at eye level.

A couple of notes:

1) I thought this was to be done with a "normal" breath and not a full one?

2) Also (at least when I did it), this was with a full tank and so I still had to add weight to account for gas to be consumed during the dive, so I would not come up light at the end and not be able to hold my stop.