BCD Advice

[jon0881]

Hi,

Ive just got through my open water :rolleyes: and have started to collect some kit. (as in my post below)
http://www.bsacforum.co.uk/forums/showthread.php?t=18726

Monday was the first day i used the regs and the BCD. The regs had a hole in the HP SPG hose but luckily i asked my instructor to bring another set of regs. The BCD felt very comfortable on the surface. I used a Med/Large in the school and had the waist adjusters to the max limit :D . The Mares Vector Chrome i have is a Large. I was surprised when i put it on that i used all of the adjustment on the shoulder straps (short, not long).

Im obviously still learning but i felt my buoyancy and position in the water was pretty spot-on with the school BCD on my last dive . I didnt have to work hard at all. This time with the Mares i felt more comfortable but my positioning was much more vertical despite rolling forward to adjust the air in my jacket. As a result i was wasting lots of energy finning up and forward, i was knackered. Apart from the BCD i was wearing the same kit. I did however take 6kg of weight instead of 9kg on my last 'good' dive. i would have thought the lower weight would have had an opposite effect if it was going to cause a problem.

Since ive already got the kit i would appreciate some pointers, im booking some pool dives for practice just in case its just a case of getting used to it.

Best wishes

Jon

[Maria CM]

Hi Jon,

What a pain about the hose:(

Ref BC: may well just be a case of getting used to it. I'm not an instructor so not much help I'm afraid, but might be worth asking your own instructor to have a look at you in the water when next in the pool to see what is happening. Maybe your tank was being held at a different level? New kit always takes a bit of settling into.

Are your weights integrated now, or were they before?

Hope someone better able to help posts for you shortly.

best wishes,

maria

[PeteM]

Go diving with it more and get someone else to look at you when you are in the natural position. It is different so it will feel different, sometimes a minuscule difference in trim can feel huge, someone else can more easily judge how far out of balance you are, if it is not much then it could be just a case of getting used to it. I've had this in the past when I have changed kit (most recently when I changed a stage cylinder), I seemed to spend the whole of the first couple of dives trying to get my trim right rather than enjoying myself. After a while I got used to it.

If it is not then, in no particular order:-

You can adjust your trim by moving the cylinder; up pushes you head down, down pushes you feet down.
Have you changed the position of the weight? Moving from weight belt to integrated can feel very weird. If that is the case switch back to the belt for a few dives, once you are happy move the weight a bit at a time. You may also be able to move some of the weight to trim pockets on the BC.
If you were diving on 9Kg but are now on 6Kg but other than the BC and regs on the same kit you were definitely over weighted. The move to more accurate weighting again feels odd, at depth breathing and adjusting gas in the BC will generally effect your buoyancy more slowly but shallow things will happen far faster. With weighting correct then things are far more linear. What ever you do, do not put the weight back on, if you don't need it then it will increase your gas consumption and bouyancy issues.
Have you changed any other kit, even minor stuff? Different fins can make a big difference to trim. An old wetsuit or under suit reacts differently to a new one of the same type.


HTH

Pete

[jon0881]

Jeez this forum is fantastic. Im a member of plenty of forums and this is by far the most friendly, un-cliquey (SP?) and informative.

Th BCD does not have integrated weights so i was still using the belt. Like i say, i will be in the pool a few times now so its a good chance to get used to the kit. Obviously i wont be wearing as much gear so i cannot double check my weight. I will also play with the height of the cylinder, i was using a 12L stubby i think but i do remember thinking it was a bit low. Sometimes i overcompensate because when i put my head back to look up at something i hate bashing my head on the regs.

Happy and safe diving everyone.

/Jon

[ChristianG]

Th BCD does not have integrated weights so i was still using the belt. Like i say, i will be in the pool a few times now so its a good chance to get used to the kit. Obviously i wont be wearing as much gear so i cannot double check my weight. I will also play with the height of the cylinder, i was using a 12L stubby i think but i do remember thinking it was a bit low. Sometimes i overcompensate because when i put my head back to look up at something i hate bashing my head on the regs.
Jon,

The pool is where you should use all your kit because otherwise, quite frankly, you are chasing your own tail. Yes, the pool is (slightly) different to salt water as a result of buoyancy considerations but largely it gives you a safe environment to test out your gear, and get others to check out that you are doing it right.

What am I saying here? The pool is not the time that you strip to what is comfortable.

[jon0881]

Wow it will be pretty warm in the 25c pool will 14mm of neoprene on. I will give it a bash though i guess.

[Nigel Hewitt]

What am I saying here? The pool is not the time that you strip to what is comfortable.
ROTFL.

I remember reworking the trim on the new rebreather in the full cold water gear - undersuit, gloves, hood and all - in a nice warm pool. I was moving weights about, clipping and unclipping stages, rebuilding weight belts and loading and unloading trim pockets for about an hour. I finally got it all set up so it was an effortless horizontal hang but when I stripped off the undersuit it looked like it had flooded.

Boil-in-the-bag diver anybody? :eek:

Actually my gloves and hood are 1.4Kgs of bouyancy so they have to be part of the equation.

[jon0881]

Its a good point, even with just my shortie on i am positively boyant. Makes snorkeling a little more difficult but at least im warm!