Weight placement? Makes me roll face up!

[Ladyvalea]

Ok last weekend I tried to go diving in a 5mm wetsuit with a 3mm vest under it and played around with addin an additional 2 pounds of soft weight in the shoulder weight pouch on my Atoms lx BC .. "so now I have 4lbs in each shoulder pocket.so 8lbs total in my should pouches with 5lbs each in the intergrated waist ..so 18lbs But I notice that I felt like when I hover ...My body wanted to roll around and float face up and tank down. Is this due to excess weight in the pouches next to the tanks? Or maybe it was just me? I didn't do a weight check because I got to cold! the water was 48 degrees.. and stayed in only for 20mins..I didn't want to add or minus weights .to cold ... I'm still learning about "Trim"

Oh, plus Why is it that I always have a ton of water in my BC bladder? hubby says I hold down the wrong button on the inflator? any ideas? Thanks again

 

[gcbryan]

Whether it's holding down the wrong button (vent) when you want to inflate or just holding down the vent botton for too long after all the air is vented would cause this.

Regarding the trim problem...when you say hover this is when you are in the horizontal position right? I'm sure you just need to do a weight check to make sure that you don't have too much weight and then play around with trim weights and get more dives in so that you have a little more control over your body underwater.

 

[redrover]

You say shoulder weight. I looked up the Atmos (not Atoms right?) and it says Rear "Trim" Weight Pockets Located on the back of the harness
I can only tolerate the rolly polly level with 1# each trim pocket (on the cam bands.) Trim was good, great actually with 2# each pocket however stability was nonexistent. J
I also have a steel tank (heavy) but not rolling with out weight in the trim pockets.

I have found weight placement a tedious trial and error exercise. But do recommend doing a weight check when adding more neoprene, particularly 3ml in one location (your trunk) that will throw weight placement out of whack. Or it would have for me, I am short and can tell a 3ml bootie from a 5 ml.

I do not release air via inflator button however am prone to pull the butt or shoulder dump without rolling to tilt the release end up and get water in vs the last bit of air out. When certain there is air in there, by repeating the same mistake over and over it is impressive how much water I can get in.

 

[TSandM]

I think diving is a lot like learning to ride a bicycle, except the bicycle is on your back. There is a learning curve to balancing the gear, and nobody really talks about it. When I started diving, I went over on my back at the slightest provocation, but as I kept at it, I learned how to balance my gear.

Your tank is a big weight on top of you, and it isn't really counterbalanced with any kind of "keel" (weight placed centrally on your belly, to resist the turning motion), so if the tank gets a little to one side, it's going to want to head for the bottom. It just takes time to learn how to keep that tank in the center above you, so it doesn't do that. Eventually, you can nicely control the weight so that you can roll a little to one side, or over on your back, and control it.

Edited to add that, if you are overweighted, the shifting of the excess gas in your BC bladder when you begin to turn will accelerate your roll. The fact that you have a bunch of water in the BC at the end of the dive suggests that you are doing a whole bunch of venting, which goes along with overweighting and excessive air in the BC. Have you done a formal weight check?

 

[don Francisco]

When most folks think of managing weights for better trim they tend to focus on pitch- heads up or down trim. You've encountered the second aspect of trim, roll - sideways, back up or down trim.

If you think about a boat for a moment, you probably know that putting too large a load high in the boat creates a risk of capsizing. Likewise, if the center of gravity is too high (towards the back in horizontal trim) there'll be a tendancy for a diver to roll over. Without outside forces any bouyant body will assume a trim with the center of gravity directly below the center of bouyancy.

You basicly have two choices, practice balancing the load up there and counter-reacting when you start to roll, or re-arranging the placement of your ballast so as to bring your center of gravity down towards the mid-line of your body while bringing the center of bouyancy higher (towards the back).

With steel tanks especially, back inflate BCs are nice because the inflated wings tend to flex up to bring the center of lift closer to the line of the tank. Otherwise manage rolling issues by shifting ballast towards your belly until you acheive roll neutrality or as close to it as possible. Unless there's a reason not to, you might also consider using an aluminum tank.

In many cases you may never achieve totally neutral trim for either pitch or roll and have to use skill to compensate, but getting as close as possible is preferable to fighting nature.

 

[Teamcasa]

Good advice so far.
Excess water does speak to excess venting or venting by using the inflator button. DonÃÕ get too worried about being overweight yet, with more dives you will gain the experience and practice necessary to determine the right amount of weight you need. At 18 lbs and the wetsuit you are using, I doubt you are too far overweighed.

As for rolling over, this too will work itself out as you dive more. Try to keep your heavy weights in the front part of the weight pockets to start with. Reduce the weight in your trim pockets as they are out by your shoulders they will tend to promote rolling, move the trim closer to your bodyÃÔ center. (Tank strap weights vs trim pockets.)

All in all, you will learn what works best for you, your diving configuration and diving style. It also helps to have a good mentor to air you in making some of these decisions.

Have fun, keep diving!

 

[oly5050user]

Ok last weekend I tried to go diving in a 5mm wetsuit with a 3mm vest under it and played around with addin an additional 2 pounds of soft weight in the shoulder weight pouch on my Atoms lx BC .. "so now I have 4lbs in each shoulder pocket.so 8lbs total in my should pouches with 5lbs each in the intergrated waist ..so 18lbs But I notice that I felt like when I hover ...My body wanted to roll around and float face up and tank down. Is this due to excess weight in the pouches next to the tanks? Or maybe it was just me? I didn't do a weight check because I got to cold! the water was 48 degrees.. and stayed in only for 20mins..I didn't want to add or minus weights .to cold ... I'm still learning about "Trim"

Oh, plus Why is it that I always have a ton of water in my BC bladder? hubby says I hold down the wrong button on the inflator? any ideas? Thanks again

You did not state what your weight is for us to estimate how much weight you need,but using 18 lbs with a 5mm suit and a 3mm vest sounds like too much weight.
The reason you have water in the bcd is that you are most likely holding the button down to deflate while trying to descend.If you are properly weighed you can let the air out of the bcd on the surface and still float(barely) while slowly breathing and start descent by exhaling completely.Drop a few feet and pressure comes into play by decreasing the volume of your suit making you more negative. The BCD inf/deflate control is never underwater while attempting to first descend this way.So next time let out all of the air in bcd,try hold a deep breath on surface and see if you float,if not you have way too much weight.
To give you an idea I use 10lb of weight in salt water with a 5mm suit and 3mm vest/hood attached when I use my nikonos/ike 150m strobe system to photograph with.I use 12lb with the same setup when I go digital system(much lighter strobe).That is with an alum 63 cu tank,I can go with a bit less with a alum 80.I am 6' tall and weigh in at 170-175 lbs.
As to 48 degree water in a 5 mm suit,you handle cold better than I do,I would never attempt that.I go dry at 68 degree water.