Question about exceeding the 'loadable weight' of a BCD

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Aerobics111

Registered
Messages
62
Reaction score
8
Location
USA
# of dives
25 - 49
I have an Aqua Lung Axiom BCD and the loadable weight is listed in the size chart attached, which is 30 lbs for the size I'm wearing.

In case I need 32 lbs to get down, what's the consequence of just loading extra 1 lbs into each releasable pocket? Or I need a weight belt for the 2 lbs.

Thanks!
 

Attachments

  • Screen Shot 2021-12-22 at 11.30.12.png
    Screen Shot 2021-12-22 at 11.30.12.png
    345.9 KB · Views: 133
Hi! I use an Aqualung BC as well, with similar guidance on weight, etc. My understanding is that the guidance is based on the lift capability of the bladder and ability of the locking pockets to secure the amount of weight you'll be loading without the clip failing. I'm right at capacity (30lbs) for mine if I'm diving in a 7mm. I tend to bring a few extra pounds when I dive with students and often load up the BC with 34 pounds in that scenario. I use the trim pockets to load about 10 of the pounds and place the rest of the weight in the pockets. Am I exceeding the lift capacity of the BC? Possibly. But I'm also wearing a 7mm suit, 5mm gloves and boots in that set up as well. So, if I need to dump weight in an emergency, it wouldn't be a problem drop the pockets and have plenty of buoyancy in the BC, suit and accessories. So far the pocket clips have held up fine. Also, there seems to be no trim issues or anything. The BC dives the same in that scenario as it does when I'm loaded with 8 lbs on a reef in the Caribbean! :)
 
That's a lot of weight to cram into 2 integrated pockets! It could be tough to get 3 x 5 lb weights in each weight pouch. I've been able to get 22-24 lbs in (which is what I needed) when in a 7mm suit - I use the AquaLung Zuma travel BC. To get an extra few pounds in, you could use a weight pocket such as the following - just attach it to your tank strap.

 
That's a lot of weight to cram into 2 integrated pockets! It could be tough to get 3 x 5 lb weights in each weight pouch. I've been able to get 22-24 lbs in (which is what I needed) when in a 7mm suit - I use the AquaLung Zuma travel BC. To get an extra few pounds in, you could use a weight pocket such as the following - just attach it to your tank strap.

Good info! Most of those Aqualung BCs come with trim pockets on the tank strap that will accommodate 5lb weights. Mine came with two. If not, Aqualung makes nice trim pockets you can buy and install on the strap as suggested!
 
Good info! Most of those Aqualung BCs come with trim pockets on the tank strap that will accommodate 5lb weights. Mine came with two. If not, Aqualung makes nice trim pockets you can buy and install on the strap as suggested!

Yes!! My Zuma, although new, is one of the BC's that doesn't have those extra trim pockets. I think they're a great feature - unfortunately I have to go with option B!!

To address the weight belt option, I have no rear end so really have to tighten the belt to keep it from sliding down. Hope I can keep getting the weight I need in the integrated pockets. :)
 
My understanding is that the guidance is based on the lift capability of the bladder and ability of the locking pockets to secure the amount of weight you'll be loading without the clip failing.
Thanks this makes a lot of sense! Given that I have trouble going down, the lift capacity wouldn't be a concern but you are right the clip needs to be strong enough to hold the pocket from slipping out.
I use the trim pockets to load about 10 of the pounds and place the rest of the weight in the pockets.
The BC does come with two trim pockets in the back and I put 5 lbs in each. Therefore I'll need to put 11 lbs in each of the releasable pocket to make the total 32 lbs.
 
That's a lot of weight to cram into 2 integrated pockets! It could be tough to get 3 x 5 lb weights in each weight pouch. I've been able to get 22-24 lbs in (which is what I needed) when in a 7mm suit - I use the AquaLung Zuma travel BC. To get an extra few pounds in, you could use a weight pocket such as the following - just attach it to your tank strap.

Thank you. Yes the BC does come with two trim pockets in the back and I put 5 lbs in each. So I only need to put 11 lbs in each integrated pocket.

I knew there must be a good reason for the weight limit in the size chart but didn't know what it was. I hope the design margin of the BCD would allow 1 extra pound in each pocket.
 
I have an Aqua Lung Axiom BCD and the loadable weight is listed in the size chart attached, which is 30 lbs for the size I'm wearing.

In case I need 32 lbs to get down, what's the consequence of just loading extra 1 lbs into each releasable pocket? Or I need a weight belt for the 2 lbs.

Thanks!
this response is going to sound very harsh but it is not personal and in your best interest from a safety perspective, so please roll with it and answer the questions below so we can help you.

You shouldn't need 32lbs to get down. Requiring that much lead means that you are either severely obese and shouldn't be diving, or are diving an unsafe configuration with regards to thermal protection *something like a 7mm farmer john in size 4XL*.
If you do not fit in that category, then you don't need that much lead and there is an underlying issue with regards to why you THINK you need that much lead to get down.

Are you diving in salt or fresh?
What tanks are you diving?
What are you wearing for exposure protection?

A good rule of thumb is 2lbs/mm for a full wetsuits, i.e. 10lbs for a 5mm, 14lbs for a 7mm, plus about 4lbs for an AL80 for fresh water and an extra 4-6lbs if diving salt.
If you need more than that and aren't seriously obese, then it is typically because you don't have control of your body. That comes in the form of bad breathing *exhale all the way*, little Nemo fins *put your left hand on inflator and right hand holding onto something else*, and very frequently some wild foot action *cross your ankles*. Most instructors are lazy/ignorant and they solve this problem by overweighting a diver, but that just creates a dangerous situation in the event of a failed BCD causing people to think they need to ditch weights. No bueno.
 
Hi! I use an Aqualung BC as well, with similar guidance on weight, etc. My understanding is that the guidance is based on the lift capability of the bladder and ability of the locking pockets to secure the amount of weight you'll be loading without the clip failing. I'm right at capacity (30lbs) for mine if I'm diving in a 7mm. I tend to bring a few extra pounds when I dive with students and often load up the BC with 34 pounds in that scenario. I use the trim pockets to load about 10 of the pounds and place the rest of the weight in the pockets. Am I exceeding the lift capacity of the BC? Possibly. But I'm also wearing a 7mm suit, 5mm gloves and boots in that set up as well. So, if I need to dump weight in an emergency, it wouldn't be a problem drop the pockets and have plenty of buoyancy in the BC, suit and accessories. So far the pocket clips have held up fine. Also, there seems to be no trim issues or anything. The BC dives the same in that scenario as it does when I'm loaded with 8 lbs on a reef in the Caribbean! :)
Actually one more question. When you put in the extra weight, did you put them in the zipper pocket or the releasable pocket?
I suppose if the former, then there's no risk of the clip failing but of course the extra weight cannot quick release. But quick release 20 lbs might already be enough?
 

Attachments

  • Screen Shot 2021-12-22 at 13.44.57.png
    Screen Shot 2021-12-22 at 13.44.57.png
    251.5 KB · Views: 86
this response is going to sound very harsh but it is not personal and in your best interest from a safety perspective, so please roll with it and answer the questions below so we can help you.

You shouldn't need 32lbs to get down. Requiring that much lead means that you are either severely obese and shouldn't be diving, or are diving an unsafe configuration with regards to thermal protection *something like a 7mm farmer john in size 4XL*.
If you do not fit in that category, then you don't need that much lead and there is an underlying issue with regards to why you THINK you need that much lead to get down.

Are you diving in salt or fresh?
What tanks are you diving?
What are you wearing for exposure protection?

A good rule of thumb is 2lbs/mm for a full wetsuits, i.e. 10lbs for a 5mm, 14lbs for a 7mm, plus about 4lbs for an AL80 for fresh water and an extra 4-6lbs if diving salt.
If you need more than that and aren't seriously obese, then it is typically because you don't have control of your body. That comes in the form of bad breathing *exhale all the way*, little Nemo fins *put your left hand on inflator and right hand holding onto something else*, and very frequently some wild foot action *cross your ankles*. Most instructors are lazy/ignorant and they solve this problem by overweighting a diver, but that just creates a dangerous situation in the event of a failed BCD causing people to think they need to ditch weights. No bueno.
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!
 

Back
Top Bottom