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robhrapczynski
08-26-2010, 22:16
I recently went on a dive at Dutch Springs in PA with a few friends and had a problem going under. A little information about me: I'm 6 foot 3 and 210 pounds. I was wearing 28lbs on a belt and 6lbs in my BC. I also had a XXL 7.5mm wetsuit on with a hood. I have 16 dives registered but almost exclusively in warm weather.

I thought this would be plenty of weight but it didn't seem even close. I had to kick vigorously to get under. The further I went down the easier it was and I had no problems with buoyancy under 35ft. (Holding at 15 feet was impossible)

My wetsuit/hood seemed to be holding air in them. This would clearly make it hard to go under. I tried sitting submerged in water for ten minutes to fully get "wet" and tried getting all the air bubbles out.

Can anyone suggest possible problems and solutions? Thanks. This is the second time this has happened to me at Dutch.

navyhmc
08-26-2010, 22:24
One piece or john and jacket? How much weight did you need in previous or no wetsuit-fresh or salt water? Was all the air out of your BCD as well?

robhrapczynski
08-26-2010, 22:35
It was a john and jacket. I don't have my book with me right now but I believe I wore 16-18lbs in Cozumel. Haha yes all the air was out of my BCD. I'm only a semi noob.

When we originally tried to descend, I was able to barely get my head underwater. When I continued to let the air out of my BCD and slowly breathed out, I got to approx 5ft before popping back up.

scubastud
08-26-2010, 22:49
A lot of previous threads about this subject. My first dive or two I thought I was underweight, even though I swore I wasn't someone told me I may be kicking my feet. I crossed my legs at the ankles and low and behold I sank!

navyhmc
08-26-2010, 23:07
It was a john and jacket. I don't have my book with me right now but I believe I wore 16-18lbs in Cozumel. Haha yes all the air was out of my BCD. I'm only a semi noob.

When we originally tried to descend, I was able to barely get my head underwater. When I continued to let the air out of my BCD and slowly breathed out, I got to approx 5ft before popping back up.

No insult intended...I did that a few times, thought I had all the air out, low and behold! Then I sunk. :smiley36:

With a 7.5 John and Jacket, you've got 15mm on your core-that's a lot of neophrene! If you bobbed at 5', I'd add another 4 lbs and go from there. Add a small hole to the top of your hood will help burp it too. A little unzip on your jacket at the start will help get rid of some of the air trapped in the suit as well. Also as hard as it can be in colder water, either make a slow entry into the water to force the air out the neck or prime the suit with a little warm water if the water is really cold.

I don't think you're doing anything wrong, you just have a lot of insulation there to sink. I'd expect you can drop a couple pounds after 15-20 dives in it too as it compresses some of the neophrene air pockets down with use.

tonka97
08-27-2010, 05:39
No insult intended...I did that a few times, thought I had all the air out, low and behold! Then I sunk. :smiley36:

With a 7.5 John and Jacket, you've got 15mm on your core-that's a lot of neophrene! If you bobbed at 5', I'd add another 4 lbs and go from there. Add a small hole to the top of your hood will help burp it too. A little unzip on your jacket at the start will help get rid of some of the air trapped in the suit as well. Also as hard as it can be in colder water, either make a slow entry into the water to force the air out the neck or prime the suit with a little warm water if the water is really cold.

I don't think you're doing anything wrong, you just have a lot of insulation there to sink. I'd expect you can drop a couple pounds after 15-20 dives in it too as it compresses some of the neophrene air pockets down with use.

Great informative and helpful post!

Noob
08-27-2010, 06:41
I'm with Navy. I dive 26-28lbs and I'm 30lbs lighter then you with a 5mm farmer john. You will probably be approx 32-35lbs of lead.

bassplayer
08-27-2010, 07:02
I dive a Henderson 7mm one piece XXL 5'10 240lbs I currently use 32lb in fresh water. Another tip, make sure you blow ALL the air out of your lungs to start your descent, I was guilty of that one.

Rileybri
08-27-2010, 07:33
ok so for perspective I am 5 10' and 205 lbs. I use a 5/7 mm one piece and 5 hood and gloves and use 14-16lbs on my belt, dive a steel 72 tank and a 5 lb back plate. Try venting your hood (a forum search will bring you to info on how to do this). Also try burping you wet suit after you put it on. As a new diver I was having smiler issues and found I was just breathing to hard on the deck and needed to slow down a bit and get more air out of my longs. Now I drop like a stone!

cam
08-27-2010, 09:17
The hood and wetsuit burping tricks helped me out in the beginning. And, after observing a number of students (myself included), I think many of us tend to have an reflexive instinct to take a deep breath before going under water. That in itself can be just enough bouyancy to keep you above that first 5' or so. So inhaling a lower volume near the surface might be enough to get you going on your decent. Having said that, you still need to deal with the ascent after the dive because your tank will be lighter and your bouyancy will be greater. You don't want to miss your safety stop or subject yourself to an uncontrolled ascent.

Herbdb
08-27-2010, 10:44
Like others have said, try a little more weight at first. My experience was about the same as yours my first dive at Dutch Springs. I was all over the place with my buoyancy control, especially when above 25'. I was the guy who had fins out of the water trying to get back down.

The biggest issue is the amount of exposure protection we have to wear. Once you learn to stay ahead of these changes by adding or dumping air as you transit the depths where the changes are the greatest, you will be able to get rid of some of the weight.

You got good advise to add weight now then as you get used to the changes you will be able to cut the weight. I weigh 270 and used 32 pounds with a similar suit and an aluminum 80 tank, so I suspect you will be able to do better once you get the techniques figured out.

scubadiver888
08-27-2010, 11:39
It was a john and jacket. I don't have my book with me right now but I believe I wore 16-18lbs in Cozumel. Haha yes all the air was out of my BCD. I'm only a semi noob.

When we originally tried to descend, I was able to barely get my head underwater. When I continued to let the air out of my BCD and slowly breathed out, I got to approx 5ft before popping back up.

As navy said, even experienced divers can occasionally leave a little air in their BCD. For my BCD, I found it impossible to get all the air to the exhaust hose. I found it easier to get it to a dump valve. I use the hose to dump most of it then I can get a few INCHES underwater I'll roll to get the air at the dump valve and pull no it. When I get down to 10 feet I'll try to dump a little more and sure enough a little moer comes out.

Additionally, the way to put a hole in your hood, as navy suggested, is to heat up a nail and stick it through the hood. I usually put my hood on, feel around the top for were the air might be getting stuck, mark it with a bar of soap, take the hood off then use the heated nail trick.

I'd also suggest working the suit before you get in the water. I will make sure the suit is VERY snug to my crotch and arm pits. Those are the two areas air tends to get trapped the most.

Finally, 34 lbs total is in the ball park for your size and what you are wearing but there is a strong change you need more. I dive with steel cylinders, similar exposure suit and 26 lbs. I think if I switched to AL80 I'd have to add another 8 lbs. This would put me and you on par. However, I wear 12 lbs in the Caribbean with a 3mm wetsuit. Lose the suit and I can dive with around 8 lbs. How much do you wear in warm water? If you are wearing more than me in warm water, you probably have to wear more in cold water as well.