Problems with buoyancy and weighting

[chris3536]

Dear Friends,

I come to you seeking advice/help. I am a newly certified diver. (July 02) I prior to my ceritification, I purchased a new Sea-Quest Pro QD+ BC from my local dive shop. During my 4 certification dives I dove like a champ! I really had no buoyancy problems. I had no problems decending, acending, or maintaining my buoyancy during the dive.

Once certified, I made once dive in a local quarry and 2 recent dives in Riviera Maya, Mexico. All 3 dives I had serious weighting issues. I needed a substantial amount of additional weight to get down. I think there might be a problem with my BC. Here are the facts and maybe some of you can give me some insight.

During all 4 certification dives in a local quarry, I wore a 3/2 wetsuit and needed 22lbs to decend. (keep in mind that I am a 330lb man)

My first dive as a certified diver 3 months later in another local quarry wearing a 6.5mm John & Jacket I needed 43lbs to decend.

My first dive in Riviera Maya, Mexico (and the ocean for that matter) required 30lbs to get down. (wearing the same 3/2 I got certified with)

My second dive in Riviera Maya, wearing a 3mm sleeveless shorty required 32 lbs to get down.

I can't figure out why the increase in weight was so great! Once I got down, my buoyancy was fine. I had no problem maintaining buoyancy and performed 2 really good safety stops in Mexico.

The problem of constantly having to add and keep adding weight to get me down was a pain! It made me feel uncomfortable and self conscience. The whole experience really made me skip the last 2 days of diving I had plan.

My first thought is there is something wrong with my BC.....Any thoughts would be appreciated.

 

[ckharlan66]

I can't say for sure what is causing the difference but I would suspect it is the combination of sea water being more dense than fresh (you will always need more weight in the ocean.) and as a newly certified diver out on your first ocean dive you where a little nervous. Being nervous would cause you not to exhale totally and make you more buoyant.

I am sure that others will weigh in soon with more thoughts.

Good luck and remember you will start to shed the weights as you gain experience and comfort.

Chad

 

[nk5]

Base on what you described, I don't think there is any problem with your BC. You must add additional weight (in your case significant amounts) when you dive with a thick Wetsuit. You probably wear a XXL, and you need weight to offset all that amount of neoprene.

There are other factors that you should consider. I have found that the type, size, and pressure of tanks can effect your bouyency significantly. Some BC's are more bouyent than others. Wetsuits lose a little of their bouyency as they wear out and get old.

I suggest you go back to the same place you did your OW and do a dive wearing the same exact gear and tank. Let us know how you do. :drown:

 

[mddolson]

Chris3536 bubbled: ". (keep in mind that I am a 330lb man)
My first dive as a certified diver 3 months later in another local quarry wearing a 6.5mm John & Jacket I needed 43lbs to decend.

Chris,
as a general rull of thumb (for a 6.5/7mm wet suit) I use 10% of your weight + 6 - 10 lbs. for fresh water.

At 330 lbs ( 33 + 6 to 10) = 39 to 43 lbs.
The range is due to differences in body density. The 43 lbs puts you right in the range I'd expect for a new diver.

I do not see any prblem with your BC based on this info.

Most Newly certified divers have a little anxiety.
This tends to make their air consumption higher than more experienced divers. Breathing tends to be at the higer end of your lung capacity, and this require more weight.
As divers become more experienced and relaxed, tey typically reduce their lead by 3 to 5 pounds after a few years.

You can check your weighting yourself:
Empty your BC by dunking yourself chin deep and pressing deflate button , while holding it about your head.
(most newbies forget to dunk their shoulders and trap air in their BC)
In water too deep to stand, remain motionless in the water, breathing (through your regulator) you should float just about at the top of your mask or eye brow level. (neutral)
Exhale all the air in your lungs and you should start to sink.
If you don't sink your too light, add a few pounds of lead.

Some times divers will do this exercise ok , but they complain they pop back up as soon as they start swiming.
The problem here is lungs too full, try to trelax and breath normally.

regards

MikeD

 

[herman]

The above check is correct IF you are using an almost empty tank- 400-500 psi. If you are using a full tank, you must add 4 lbs to the total weight, otherwise you will be about 4 lbs under weighted at the end of the dive. A PITA for an experienced diver, a minor emergency for some newbie divers. The 4 lb additional is assuming a 80cf tank, other tanks will require adding more or less weight depending on the capacity of the tank.

 

[Welshman]

I can't see that there is any problem with your BC. If there was, such as a leak in the bladder you would soon know about it.

Herman and Mike are right. Just get your weighting right with a 500 psi full tank as per the PADI and I expect evry other manual.

Enjoy your diving. You will find as you become more experienced and relaxed in the water that your air consumption will improve and you will need less weight. Recommend you take a Peak Performance Buoyancy course. I found this far and away the most valuable thing I did after I had passed my OW.

Regards

 

[Ari]

1. You're a big guy, hence you need big weight.

2. Salt water call for more weight than fresh water.

3. Thick wetsuits are also big weight consumers.

4. It will get better with time.

Imediatelly coming out of AOW class i used about 24 # to go down. These days I am using 18 # for the same conditions, a 25% weight reduction. When using a steel tank I can even go down to 11#.

It might be that I have more equipment, but I think that the major issue is that I am more relaxed in the water, more experienced in using my BCD, and have better control allaround.

Take your time, get better used to you equipment, harpen your skills and you will find that your weighting also gets better.

Ari

 

[MgicTwnger]

Take a bouyancy class, like PADI's Peak Performance Bouyancy. It really helped me: less lead, better trim, and a higher comfort level. Working one-on-one with the instructor made all the difference.