Bcd Question

[TheHuth]

Last night I finished up my 9th total dive, and 5th on my Scubapro Seahawk BCD. I've noticed a few consistent issues, and am hoping for some seasoned pro advice. Off the bat I acknowledge that I'm still very new to diving, so it could just be me.

1) I tend to roll no matter what position I am in. Laying on my back, I want to roll to the side. Horizontal dive position, I want to roll. No matter what I want to roll.

2) If I'm laying on my back, my tank is always flopping to one side or another, further aggravating the above.

3) It is very hard to vent off air. If I need to dump air from the BCD, I have found that by rolling while holding the vent, air will bleed off. The problem is, it may be hard to get in to the right position to get the air out, and I have had several runaway ascents. Luckily all from shallow depths.

I'm starting to think that this back inflate style BCD really sucks. But again, I dont have a ton of experience, so it might just be that I need to gain more experience.

 

[cool_hardware52]

One of the primary benefits of a genuine Back Plate and Wing vs fabric BC's how secure the cylinder is. The wide rigid plate takes the roll out of the cylinder. That's hard to duplicate without a plate.

Rolling is something that can be greatly reduced by fin position. If a diver is in horizontal trim, in the classic "skydiver" position, i.e. horizontal thighs and bent knees simply spreading your legs apart so your fin blades are separated by several feet will have a huge impact on rolling. It's much easier to spin a "cylinder" i,e, a diver with their leg straight and fins together, than it is when the fins are 3 ft apart.

Mostly however what you need is more time in the water. I clearly remember my first few dives with a slung al 40. Off balance, rotating to one side, all sorts of problems if I had to pass off this bottle to others or take on a second one etc.

After 1/2 dozen dives it became far easier, and now I don't really notice a couple bottles on one side. You learn to compensate, and eventually it becomes second nature.

With 9 dives *everything* is challenging. Hang in there, it gets better.

Tobin

 

[redacted]

Most of your problems should go away with practice. BCDs don't cause multiple uncontrolled ascents.

Back inflate is not the issue. But it is hard to beat a back plate for tank stability.

 

[TheHuth]

Gotcha. So my takeaway here is that I just need to spend more time in the water, and things will improve over time.

 

[Montana Diver]

I had a rolling issue on my first drysuit dive. Overweighted and drysuit too large. I corrected both of those issues and love my BPW. Dive it all the time. Have you done a weight check with a 500 PSI tank. That will help you with how much to add. I dive a DUI weight harness and like how it places my weight on the edges of my hips rather than in back.
Do you have buddies that can lend you items. My LDS will allow me to try out items with the understanding that I will give them the business, I can experiment with equipment without having to buy and then resell what doesn't work well for me.

Good Luck.

Dennis

 

[rx7diver]

1) I tend to roll no matter what position I am in. Laying on my back, I want to roll to the side.

2) If I'm laying on my back, my tank is always flopping to one side or another, further aggravating the above.

TheHuth,

If you tend to roll when you are lying on your back (i.e., prone, but facing upward) with your back-mounted, full tank beneath you, then you might have your weights distributed unevenly either on your weight belt or in your weight-integrated BC (if your BC is of the weight-integrated type). Can you check this?

Safe Diving,

rx7diver

 

[Diver0001]

Last night I finished up my 9th total dive, and 5th on my Scubapro Seahawk BCD. I've noticed a few consistent issues, and am hoping for some seasoned pro advice. Off the bat I acknowledge that I'm still very new to diving, so it could just be me.

1) I tend to roll no matter what position I am in. Laying on my back, I want to roll to the side. Horizontal dive position, I want to roll. No matter what I want to roll.

2) If I'm laying on my back, my tank is always flopping to one side or another, further aggravating the above.

3) It is very hard to vent off air. If I need to dump air from the BCD, I have found that by rolling while holding the vent, air will bleed off. The problem is, it may be hard to get in to the right position to get the air out, and I have had several runaway ascents. Luckily all from shallow depths.

I'm starting to think that this back inflate style BCD really sucks. But again, I dont have a ton of experience, so it might just be that I need to gain more experience.

Your BCD is too big.

Everything you are saying is EXACTLY what I see when someone is using a BCD 1 or even 2 sizes larger than they need. If you are renting then just try a smaller size next time. If you bought that BCD then take it back and try to exchange it for a smaller one. I'm 99.55% convinced even without seeing you that I'm right about this.

As for venting, that could be aggravated by the issues with the BCD being too big or it could be a matter of technique. I'd have to see you in the water to be sure.

R..

 

[lerpy]

As has been said by a few already. First I would check the sizing of the BC, might be a bit lose allowing some "flop" in the whole system. Next make sure your weights are well distributed, and then it may just be a matter of diving and getting the hang of your buoyancy and used to how to trim yourself so you are stable. As well as was said a true BP/W may feel more stable, if renting give it a try. You only have 5 dives on the rig, and 9 dives total, could just need more practice. I now have over 300 dives, and probably upwards of 100 on my drysuit and doubles, and I am still playing with things to get nice and trim. When I first went to drysuit and doubles I was all over the place, and if I have been out of the water for several months, my first few dives are often just trying to get my trim and buoyancy back in check. Not unusual to have issues when going to new equipment until you get used to it in the water.

 

[TheHuth]

There is absolutely no chance the BCD is too big. Straight from the manufacturer, for my weight, it is the right size. However, with it on, its pretty tight. Its potentially one size too small. But I am using a 7mil wetsuit with a 5 mil hooded vest.

 

[Diver0001]

Ok that's weird. What kind of BCD is it and what size tank are you using?

R..