Question about exceeding the 'loadable weight' of a BCD

[tbone1004]

I'm very slim. 5'9'' and 150 lbs. Wear 7mm semi-dry. M size, shop thinks it fits well. Plus 7mm boots and 5mm gloves. Al 80 tank. Salt water. (Btw if I switch to Steel 100, do I take off 6 lbs?)

I agree I don't think I actually need 32 lbs but I'm very very new and not good at body control yet. Last time I dove with 24 lbs weight and couldn't go down at all. Guide gave me another 4 lbs, making total to be 28 lbs and I had to be dragged down. Then near the end of dive when we got to shallower water, I just floated to the surface with a fully deflated BCD. That's why I think on top of 28 lbs, add another 4 lbs would make sure I don't have positive buoyancy at the end of a dive.

And thank you!

I wouldn't let you get in the water with any more than 24 with an AL80 so they started you with the right amount of lead. Steel 100 would be 6lbs less. Anything more than that is an equipment solution to a skills problem.

Look at the 3 suggestions I made about your hands, feet, and breathing. That will help immensely.

 

[Aerobics111]

I wouldn't let you get in the water with any more than 24 with an AL80 so they started you with the right amount of lead. Steel 100 would be 6lbs less. Anything more than that is an equipment solution to a skills problem.

Look at the 3 suggestions I made about your hands, feet, and breathing. That will help immensely.

Thank you!

 

[scubadada]

Hi @Aerobics111

I'm just a lttle taller and more plump that you, 185#. With a 7 mm full suit, 5/3 mm hooded vest, I only need 20# with an AL80. There's a disconnect for the amount of weight you need, Not at all sure what to tell you. I just can't imagine that you need this weight.

 

[Bowers]

I agree with tbone and aerobics. I need half the weight you describe when wearing a 7mm suit and im bigger than you. I have a lot of students who do a weight check then when actually diving they can’t stay down. We surface and revisit the importance of controlled and relaxed breathing then like magic they sink with no problem

 

[Aerobics111]

I wouldn't let you get in the water with any more than 24 with an AL80 so they started you with the right amount of lead. Steel 100 would be 6lbs less. Anything more than that is an equipment solution to a skills problem.

Look at the 3 suggestions I made about your hands, feet, and breathing. That will help immensely.

I just realized there might be a difference between two piece wetsuit and one piece wetsuit? (7mm).
(Of course skill is the most important factor)

I used a two piece last time when I had trouble going down but this Fri I'll dive in a one piece.

An online weight calculator I used indicates there's a 6 lbs difference. It seems a lot, so I'm not sure how true this is.

Estimated Diving Weight Calculator | DiveBuddy.com

This scuba diving calculator determines the estimated diving weight needed for proper buoyancy.

www.divebuddy.com

"In Salt water, weighing 152 lbs, with a 7mm one-piece wet suit with gloves/hood/boots and Aluminum 80:
You will need an estimated 24 lbs of weight (+/- 2 lbs)."

"In Salt water, weighing 152 lbs, with a 7mm two-piece wet suit with gloves/hood/boots and Aluminum 80:
You will need an estimated 30 lbs of weight (+/- 3 lbs)."

 

[tbone1004]

@Aerobics111 huge difference in 2-piece vs 1-piece and I have said on this forum many times before I don't believe 7mm 2-piece suits are safe for scuba diving due to compression at depth. the weighting is about right for 24 to 30 with the 2 piece, it's a lot of neoprene.

 

[Aerobics111]

@Aerobics111 huge difference in 2-piece vs 1-piece and I have said on this forum many times before I don't believe 7mm 2-piece suits are safe for scuba diving due to compression at depth. the weighting is about right for 24 to 30 with the 2 piece, it's a lot of neoprene.

Thanks! It makes more sense now. Luckily I bought a one piece and also no need to worry about overloading my BCD. I will try out the skills you mentioned. Thanks again!

 

[boulderjohn]

The BCD you use is also a factor.

I went to Roatán a few weeks ago for 2 weeks of diving, and I stupidly left my single tank adapter home and had to rent jacket BCDs for those two weeks. I was shocked at how much more weight I needed than I normally use.

 

[boulderjohn]

I just realized there might be a difference between two piece wetsuit and one piece wetsuit? (7mm).
(Of course skill is the most important factor)

I used a two piece last time when I had trouble going down but this Fri I'll dive in a one piece.

An online weight calculator I used indicates there's a 6 lbs difference. It seems a lot, so I'm not sure how true this is.

Estimated Diving Weight Calculator | DiveBuddy.com

This scuba diving calculator determines the estimated diving weight needed for proper buoyancy.

www.divebuddy.com

"In Salt water, weighing 152 lbs, with a 7mm one-piece wet suit with gloves/hood/boots and Aluminum 80:
You will need an estimated 24 lbs of weight (+/- 2 lbs)."

"In Salt water, weighing 152 lbs, with a 7mm two-piece wet suit with gloves/hood/boots and Aluminum 80:
You will need an estimated 30 lbs of weight (+/- 3 lbs)."

In my post above, I mentioned that I had to use jacket BCDs in Roatán and could not believe how much extra weight I needed. I just used that weight calculator to see what it said, and it told me I needed 50% more weight than I actually used. Stay away from that calculator!

 

[BRT]

I'm very slim. 5'9'' and 150 lbs. Wear 7mm semi-dry. M size, shop thinks it fits well. Plus 7mm boots and 5mm gloves. Al 80 tank. Salt water. (Btw if I switch to Steel 100, do I take off 6 lbs?)

I agree I don't think I actually need 32 lbs but I'm very very new and not good at body control yet. Last time I dove with 24 lbs weight and couldn't go down at all. Guide gave me another 4 lbs, making total to be 28 lbs and I had to be dragged down. Then near the end of dive when we got to shallower water, I just floated to the surface with a fully deflated BCD. That's why I think on top of 28 lbs, add another 4 lbs would make sure I don't have positive buoyancy at the end of a dive.

And thank you!

Get a DUI weight harness and divide the weight. It will also allow you to change your trim up and down on your body. Different people dive with different weights. Less is nice, but floating up at the end of a dive is terrible. Don't let anybody tell you to take off weight unless they are willing to carry the additional for you through the end of the dive in case you need it. I had a know it all divemaster tell me they would have spares, but they lied. I ended up with a big rock off of the bottom.