Question Figuring out weight and trim

[JPaulH]

Hi all, this is my first post. I just recently passed my OW, excited, and want to get in the water as often as possible. I have a trip to Hawaii booked in November so want to nail down my buoyancy and trim.

At a pool session I had a lot of trouble trying to get buoyant, I could stay level with my fins on the pool floor, but off the floor I either sank flat or lifted up head first/ feet heavy. A little about me; Male, about 200lbs, 6ft and in the pool was wearing shorts, rash guard with Scuba Pro Go travel fins. BCD was from the shop, not mine. I had 16lbs of weight on a belt (which I think was too much), 2lbs in each dump-able pocket and a 1lb weight in non-dump-able pockets. I did dump the dump-able weights but still could not get level.

Is this too much weight? What should I try with weight distribution next time?

Thanks in advance, really appreciated. I am reading as much as I can before next pool session.

Paul

 

[grantctobin]

Hi all, this is my first post. I just recently passed my OW, excited, and want to get in the water as often as possible. I have a trip to Hawaii booked in November so want to nail down my buoyancy and trim.

At a pool session I had a lot of trouble trying to get buoyant, I could stay level with my fins on the pool floor, but off the floor I either sank flat or lifted up head first/ feet heavy. A little about me; Male, about 200lbs, 6ft and in the pool was wearing shorts, rash guard with Scuba Pro Go travel fins. BCD was from the shop, not mine. I had 16lbs of weight on a belt (which I think was too much), 2lbs in each dump-able pocket and a 1lb weight in non-dump-able pockets. I did dump the dump-able weights but still could not get level.

Is this too much weight? What should I try with weight distribution next time?

Thanks in advance, really appreciated. I am reading as much as I can before next pool session.

Paul

To confirm, you're wearing 16+2+2+1+1 = 22lb of weight with no exposure protection on? I'd bet 14-16lb overweighted, but BMI and other factors can change that.

Read this per Netdoc:

Pete Murray’s Weighting methods

Many of you will recognize the name, formerly known as NetDoc on ScubaBoard, known as The Chairman today. One of Pete’s strengths in teaching buoyancy and trim. While slightly different than my own…

divingwithkosta.wordpress.com

Then play with this:

Info - Optimal Buoyancy Computer

The Optimal Buoyancy Computer A tool to help nail buoyancy and improve safety, before you splash 1) How much lead should I carry with my new wetsuit? 2) How big a wing should I buy? 3) Will my BCD support my lead, both at the surface and when my wetsuit is compressed at depth? 4) Will my BCD...

scubaboard.com

Note, the exposure protection you'll wear in Hawaii may differ from what you're using in the pool.

 

[waterone]

Hi all, this is my first post. I just recently passed my OW, excited, and want to get in the water as often as possible. I have a trip to Hawaii booked in November so want to nail down my buoyancy and trim.

At a pool session I had a lot of trouble trying to get buoyant, I could stay level with my fins on the pool floor, but off the floor I either sank flat or lifted up head first/ feet heavy. A little about me; Male, about 200lbs, 6ft and in the pool was wearing shorts, rash guard with Scuba Pro Go travel fins. BCD was from the shop, not mine. I had 16lbs of weight on a belt (which I think was too much), 2lbs in each dump-able pocket and a 1lb weight in non-dump-able pockets. I did dump the dump-able weights but still could not get level.

Is this too much weight? What should I try with weight distribution next time?

Thanks in advance, really appreciated. I am reading as much as I can before next pool session.

Paul

I imagine you would have trouble with buoyancy with that much weight. Unless that BCD is insanely buoyant, I would try 6lb or so while carrying a few extra that i can drop individually and work from there. Normally you will need more weight as you get into diving and will drop it down as you continue, so it might seem you need more. Also make sure to test buoyancy as you get around 500 psi or so in the pool as well.

200lb @6 foot with 3mm wetsuit in Hawaii (temps currently around 78 to 80), if you needed over 12lb I'd be surprised.

 

[ibj40]

Another thing to consider is moving some of your weights away from your waist and up higher on your body.

You can get pockets designed to go on the tank strap.

I used them to help me with lower back issues, and improved my trim at the same time.

Tank Strap Trim Weight Pockets - Google Suche

 

[inquis]

19 lbs total?? Definitely too much weight in a pool (especially if that's without a wetsuit). Assuming you're using a full AL80 tank in the pool (you will have an AL80 in Hawaii), first adjust weight so you are about neutral at the end of a normal exhale WITHOUT any air in the BC. You should be able to descend by exhaling further or ascend by inhaling. Then add an additional 5 lbs of lead to compensate for the air you'll breath (from 3000 psi to 500 psi). This is your total fresh-water weighting. If you're planning to use a wetsuit in HI, wear it during your pool session.

When you get to Hawaii (salt water), you'll need to add about 6 lbs to your fresh-water weighting (this is based on your weight).

I would be surprised if you needed more than 14 lbs in Hawaii in a 3 mm wetsuit or 8 lbs in a swimsuit. (I'd recommend a 3mm suit there, though.) I'm assuming a "floaty" rental BC. Refine from there based on the amount of air in the BC at the safety stop after taking your tank down to near 500 psi. If you vent and sink quickly, drop a couple lbs for the next dive and evaluate again then.)

Without your own gear, it's a bit tough to work out trim, because usually you need distribute weight higher up (e.g., on the tank band or in built-in "trim" pockets), which is often not possible with rental gear. If you know your operator, ask them about trim pockets. It's then a matter of distributing the lead so you don't rotate when you are horizontal and stop kicking. I suggest 4-6 lbs up top for trim (won't be easily ditched, but that's OK), and the remainder on a belt or integrated pockets. It's also helpful for trim to have legs bent at the knee (straight legs will easily sink).

 

[rongoodman]

Another thing to keep in mind about trim is your posture. Moving weight around isn't going to do anything if you're limp in the water, letting your knees drop and legs dangle. It takes a little tension in your glutes to keep your body flat from shoulders to knees.

 

[TMHeimer]

I wore 12 pounds with my shorty wetsuit in the pool and 10 or 12 in my body suit in the tropics. Since I use 40 pounds with my 7 mil wetsuit (am definitely not overweighted), I am one who needs a LOT of weight and am similar in size/weight to you. SO, I would THINK you are overweighted if you were using more than me.
But everyone is different, even those with similar bodies. I'm sure you have read how to do a proper weight check. You would have to do this when you get to Hawaii.
About trim-- what Inquisit said. Trial & error. There are only so many places that you can shove weights unless you start with attaching them to the tank, etc. Buoyancy of your fins is important. Mine are big and negatively buoyant, so I put as much weight as I can in the trim shoulder BCD pockets.

 

[grantctobin]

I wore 12 pounds with my shorty wetsuit in the pool and 10 or 12 in my body suit in the tropics. Since I use 40 pounds with my 7 mil wetsuit (am definitely not overweighted), I am one who needs a LOT of weight and am similar in size/weight to you. SO, I would THINK you are overweighted if you were using more than me.
But everyone is different, even those with similar bodies. I'm sure you have read how to do a proper weight check. You would have to do this when you get to Hawaii.
About trim-- what Inquisit said. Trial & error. There are only so many places that you can shove weights unless you start with attaching them to the tank, etc. Buoyancy of your fins is important. Mine are big and negatively buoyant, so I put as much weight as I can in the trim shoulder BCD pockets.

I would estimate your weight use is a 2stdev outlier just for color

 

[mcohen1021]

Is this too much weight? What should I try with weight distribution next time?

I was at 198# a few years ago, I was using 8# for caribbean diving with log sleeve wetsuit top or shorty, and prob could have dropped to 6#.

I am now @ 168# and dove all week 2 weeks ago with 4#, with the long sleeve wetsuit top - prob could have dropped to 3. You have to be patient on the descent - many think its a race to the bottom - ITS NOT... And they're going to be the ones out of control and back on the surface 1st usually.

So, yes you are totally over-weighted. You need neutral to very slightly negative with zero air in your BC at the beginning of your dive .

Many carry an extra 2# to give away to another diver when needed. I used to, but wife has it down now.

 

[TMHeimer]

I would estimate your weight use is a 2stdev outlier just for color

No idea what that is.