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coralcrazed
09-13-2007, 18:24
I always wondered if I should carry more weight with me tha I do. I get boyant with three short blast into my bc. However, whats to keep you down if you had a bc inflator malfuncton? also can you disconect the low pressure inflator in the water when the tank is delivering air to the reg.? thanks for your help.

divingmedic
09-13-2007, 18:34
Yes you can and I had to a few weeks ago. It is best to try to keep your weight down. I know when diving a quarry and I hit 300 psi, it is hard to keep down.

DUnder
09-14-2007, 10:00
Yes you can disconnect your low pressure inflator hose underwater, you should practic it as it can be tricky sometimes. We had to perform that skill in the pool durning OW class.

crosseyed95
09-14-2007, 22:19
I agree with the above posts about keeping your weight down.

Another point to bring up is that once you get your standard weight then you can alter it if needed. I keep my weight down if doing a deeper boat dive. However, if I'm doing a 5' to 10' deep shore dive to explore rocks, then I'll add a couple pounds so that I hold the bottom better.

Just wanted to bring up that point.

coralcrazed
09-15-2007, 09:57
thank you all for the great advice. How much weight should I be adding? you said that it depends on you dive. I just want to try and get an idea. every 33 feet of dept for example. is there any charts of info that padi puts out as a guidline. Does anyone know? thanks again

Kidder
09-15-2007, 10:53
Correct me if I am wrong but isn't the amount of weight you use to be determined by empting your tank to 300 PSI or so and deflating your BC. You should have enough weight so that you just barely float. Basically you sink when you exhale.

ScubaToys Larry
09-15-2007, 10:54
thank you all for the great advice. How much weight should I be adding? you said that it depends on you dive. I just want to try and get an idea. every 33 feet of dept for example. is there any charts of info that padi puts out as a guidline. Does anyone know? thanks again

Depth does not affect weight at all. You will have to add air if your suit compresses - but doing a 2 ft dive or a 200 foot dive will not change the weight requirements.

Capt Hook
09-15-2007, 12:22
Contrary to what everyone teaches, I've found that I'm more comfortable with about 2 lb. overweighted. For me it seems easier to do safety stops while drifting.
Not saying it's right, just works for me.

ian
09-15-2007, 12:54
Contrary to what everyone teaches, I've found that I'm more comfortable with about 2 lb. overweighted. For me it seems easier to do safety stops while drifting.
Not saying it's right, just works for me.


Ka Ching!

I'm really tired of all the boasts about being able to dive in a 7mm suit with just 6 oz of lead.

When I float in a fresh water pool, I have a water line! I can't take baths because I float! You should see a photo that my Mom took of me floating in the Great Slat Lake about 30 years ago. It looks like I'm sat in a chair!

When I make sure my wetsuit is completely flooded, I have no air in my BC and I cross my feet to keep from unintentionally finning up, I need 32# of lead to sink me, my equipment and my XXL Tall 7mm wetsuit, gloves, booties and beanie.

Larry is correct in that depth doesn't affect how much weight you will need...technically.

On the other hand, the changes in the buoyancy of your wetsuit will be MUCH greater in the first 15 feet that the next 15 feet. While I understand what you're saying, Larry, if I'm intending to diveless than 20 feet, I'll add a 2# clip weight or two.

My two cents worth...

ScubaToys Larry
09-15-2007, 13:06
Hey Ian... I know exactly what you are saying... But I'd maintain if you want that extra 2 lbs for a shallow dive - may as well take it on every dive, as most all mind end up being shallow at the end! :smiley2:

I won't give someone a hard time for being 2 lbs heavy... if you need it at the end of the dive to do your safety stop comfortably - then that is not heavy... that is just right!

Splitlip
09-15-2007, 13:42
Contrary to what everyone teaches, I've found that I'm more comfortable with about 2 lb. overweighted. For me it seems easier to do safety stops while drifting.
Not saying it's right, just works for me.

I over weight by 2# as well. Helps to stand up a DSMB while at safety stop depth

coralcrazed
09-15-2007, 19:29
correct me if I'm wrong please... I understand the effects of depth on a wet suit... but what about the air in your tank as someone else had said... air is compressed to begin with in the tank but is further compressed the deeper you go. so, you will need more not less weight because at the begining of the dive you have a full tank and it will take more weight to sink it until depth has an effect on it...

there is other ways to release some gas if you know you are not caring enough weight. :smiley11::smiley2:

Splitlip
09-15-2007, 21:29
correct me if I'm wrong please... I understand the effects of depth on a wet suit... but what about the air in your tank as someone else had said... air is compressed to begin with in the tank but is further compressed the deeper you go. so, you will need more not less weight because at the begining of the dive you have a full tank and it will take more weight to sink it until depth has an effect on it...

there is other ways to release some gas if you know you are not caring enough weight. :smiley11::smiley2:

No, the buoyancy of the gas in your cylinders remains constant until you breath and exhale.
The volume of the gas inside the cylinder is not affected by depth. It is inside a vessel which can withstand more than 4000 pounds per square inch.
At depth the volume of gas you consume is greater than volume you would consume at the surface because the regulator must give it to you at the ambiant water pressure so your diaphragm will work.
Some times people remember the illustrations in most BOW publications that show the "volume" of gas in cylinders decreasing with pressure. Nothing changes with the gas in the cylinder until it is evacuated from the cylinder. At 1 atm, the gas in a cylinder that can fill a 100 cf space, can only fill a 50 cf space at 2 atm.