buoyancy question

[Kenny918]

Hey SkyAce, I'm going to suggest moving your tank up. Personally, I position mine higher than most, I like to be able to reach my tank valve and turn it. I would also try to use less lead. I am a large man 6'3" 350 big one's, and in my ranger with 3 mil shorty, fresh water, I dive with 10 lbs of lead. I can get down with 8 lbs , but I am positive on an empty tank, so I use 10. Give it a try. You can also put your trim weight pouches on the top tank band if you like. I have never used them, but they are handy, for instance, in cold water with alot of lead, the back inflation of the Zeagle tends to pitch you forward while floating on the surface. This is one example of how they can be of value.
Safe diving, Kenny

 

[don Francisco]

SkyAce- Follow all the advice you've been given so far, but remember that weight & it's location is only half the picture. Trim is affected by BOTH gravity & bouyancy. You can only do so much by moving your center of gravity.

Imagine you were a seesaw. You could push down harder on one end, or you could go around & lift the other end.

You don't say, but are you by any chance using a shorty. If so give it up and wear a full suit to get some floatation on your legs, consider fins that float, reduce total weight so you keep less air in the BC, wear your BC lower on your body, & relax so there's less air in your lungs.

You're trim problem is not unique & your biology is a factor. Generally, men have lower centers of gravity then women & atheletes more than sedentary folks, because of differences in the distribution of fat and muscle on their body. The legs of athletic men, especially cyclists & iceskaters, can be far denser than the average person, torquing them down in the water. That's why you'll see some women buying ankle weights, but don't see men doing so, they need ankle floats.

Be patient & it'll come together for you. One bright side is that it seems that you're doing all this in a pool. In salt water the additional bouyance will work in your favor.

 

[SkyAce2004]

The point of the rear weight pouches I would guess to be to not have all your weight in the ditchable pouches?

even the back trim weights have red pull handles to ditch them. *shrug*

 

[SkyAce2004]

SkyAce- Follow all the advice you've been given so far, but remember that weight & it's location is only half the picture. Trim is affected by BOTH gravity & bouyancy. You can only do so much by moving your center of gravity.

Imagine you were a seesaw. You could push down harder on one end, or you could go around & lift the other end.

You don't say, but are you by any chance using a shorty. If so give it up and wear a full suit to get some floatation on your legs, consider fins that float, reduce total weight so you keep less air in the BC, wear your BC lower on your body, & relax so there's less air in your lungs.

You're trim problem is not unique & your biology is a factor. Generally, men have lower centers of gravity then women & atheletes more than sedentary folks, because of differences in the distribution of fat and muscle on their body. The legs of athletic men, especially cyclists & iceskaters, can be far denser than the average person, torquing them down in the water. That's why you'll see some women buying ankle weights, but rarely see men doing so, they need ankle floats.

Be patient & it'll come together for you. One bright side is that it seems that you're doing all this in a pool. In salt water the additional bouyance will work in your favor.

yeah, my see-saw is more weighted on my legs. My legs are toned like you wouldnt believe. I was a cyclist for around 8 years. My upper body however, leaves much to be desired. Ill try moving the tank on my next dive, and if that doesnt help, ill buy a strap to put a a weight on the neck of my tank. I live in FL where I dont even really need a wetsuit. But I wear one for exposure protection. I had a hard enough time finding a shorty that fit. I dont know if I have the patience to find another full bodied suit.

Ill try moving the tank up on the bands some first, and if that doesnt work, ill go from there.

Thanks for all the help.

 

[Colliam7]

First and foremost make sure you're not using too much weight--experiment with a tank at pressure you normally finish a dive as per the instructions of open water courses. The next step is to put your tank a little higher up on your back. If that doesn't fix it, you can try putting some ankle weights around you tank valve. ... Unfortunately I'm realizing that this whole process could've been avoided by getting bp/w setup.

All excellent points! I had a similar isssue with my Ranger. In fact, I have some great photos of me, perfectly neutral and completely vertical. Part of the challenge is the inherent positive bouyancy characteristics of the Ranger coupled with the location of the weight. Agree with Thal's suggestion to move weight to a belt (and a proper belt). While I have put ankle weight around the tank valve, I prefer using the trim weight pouches placed on the upper cam bands. You might see what kind of trim you have with a full 3mm instead of a shorty. And, yes, it is possible to address this with a bp/w. When I was turned by the subversive BP element (I think it was a shabby looking guy in a long coat standing on a street corner who enticed me to try a bp), I quickly went horizontal with a SS BP, and half the weight I was using before, and I am now addicted. I even turned my two diving children into (bp) users. Oh, the shame of it all.

 

[don Francisco]

SkyAce, You have absolutely the worst combination possible - a fit cyclist in a shorty. Your legs are negatively bouyant, so it's like you have lead strapped to your knees.

I had a similar problem for 2 years until I gave up my shorty. One day I was sitting on a boat & noticed a woman strapping on a pair of ankle weights, I commented to my buddy that I had the opposite problem & needed to make some neoprene ankle floats. He looked at me as if I'd just landed and said "why don't you just wear a full suit?" Duh!

You might be able to correct your trim by moving weights & such, but that means that you'll be supporting the weight of your legs using your lower back muscles. Eventually that'll get to you. If fit is a problem, & you don't need the insulation consider a john.

What do you mean "I WAS a cyclist", aren't you still one?

 

[scblade27]

Keep in mind you are using a back inflate BC. If you get yourself into a slightly head down position, the air in the bladder will shift toward your legs and it should help you stay that way. If i get into a slightly head up position, the air will go towards your head and make your legs sink.

If you havn't already, try playing in different positions to see if that helps. A lot of divers are most comfortable slightly head up because thats how they were trained to dive. Breaking that habit to ensure you are perfectly horizontal or slightly head down may also help to solve a lot of your problems. Another idea is to place an ankle weight around your tank valve to help shift some weight up to see if that is the problem.

 

[SkyAce2004]

I went to move the rear trim pockets to the upper cam band yesterday, but didnt see anywhere to attach it. It attaches to the cam band itself, and then velcro's to a loop above it. There is no nylon loop to mount it to.

I REALLY dont want to wear a full wetsuit in these tropic climates. And no, I dont cycle anymore. Though I do see my bike hanging up and think to myself I should go out and ride.

I can stay horizontal if im kicking. I dont need to kick fast, the when I stop, i slowly start to creep upwards until im vertical. Im not a tech diver by any means, but it would be nice to get my trim down.

 

[LiteHedded]

you can move those pockets up to the top like i did

 

[scarefaceDM]

Here is an observation and some advice.

There are three solutions to your problem. One is not enough dive experience, which will evolve so dive alot. Two is the placement of your weight and your position in the water. Three is...you may not like this...That Zeagle may not be the right rig for you. It is a great back inflate BC but it is not right for everyone. It happens. So before I tackle the last point. Lets look at what can or may be done.

1- As everyone mentioned..move, shift, redistribute your weight. Move tank up higher.
2- Get trim weights. Attach them to your cam bands.
3- Use steel tanks instead of aluminum. You will shed a few pound off your weight belt, pockets etc. The weight of a steel tank sits nice on your back and not on your hips. Thus you become alittle more balanced.
5- There are longer trim weights that may work well. You can use ankle weights by attaching them lengthwise with tie wraps along both cam bands . Make sure they are close to the body and run along the tank.

See if this works. It is a matter of trial and error. But hit the pool with someone that has way more experience. Get an instructor to help out or a Divemaster from your local shop.

Now the RIG. what works and it truly does is a back plate and wing. Not all BC's fit everyone right. Many whom have ventured to the dark side have not regretted it. It is a way better system for balancing a RIG and making you horizontal. With a little adjustment the Backplate will be balanced and fit you like a glove. Your sinking legs will gradually disappear as you gain experience with the Plate.

Changing a few things in your dive techniques..like doing the frog kick will greatly improve your position in the water. By bending your knees and frog kicking as opposed to the traditional fin kick. You will force your body horizontal and this is truly the BEST method of finning...

But before you throw in the towel try a few things as mentioned from everyone. Get more dive experience and see if it has worked for you or not. Then consider trying a backplate and wing.

Safe dives