Buoyancy

[tursiops]

I thought I fixed that. https://drive.google.com/open?id=1WPspW1jpgXJFwBcoQi9yR7OmgzSR4VrN

In pages 17-19 of your linked article you are incorrectly using the tables for a multilevel dive. they are not designed for that, and cannot validly be used for that. I know one instructor who was fired from the shop he was working for for teaching exactly that.

 

[Jeffr13]

I'm around your age 5'11" 165# and dive with 6# in the Caribbean wearing a 1.5 ,mil heater top. I did finish a dive with 3# once bc my wife needed more at the end of a dive, but 4-6# for you I have a hard time believing when I needed 8# when I was 198#.

At 218, I would think you needed a minimum 10# for any dive.

All my open water dives have been in colder water with 7mm wetsuites. I use 20 or 22 lbs added. Its the trim I can see is different in the travel BCD. I have used a rental jacket BCD and it was so much easier. I'm sure a seasoned vet. be just fine in the travel BCD but I've been having a hard time with trim.
Thank you for any help.

 

[Jeffr13]

This is backwards, unless it is meant to be MORE head down....F1s are heavier than Eddys.

You think add the 1-2bs to tank valve adds some forward weight and slightly heavier Hollis fins would lower my feet slight. This might trim me and easier diving. My fins do float and my calves were over worked last dive.

 

[saxman242]

You think add the 1-2bs to tank valve adds some forward weight and slightly heavier Hollis fins would lower my feet slight. This might trim me and easier diving. My fins do float and my calves were over worked last dive.

Adding tank valve weight and heavier fins will just counteract each other.

 

[Jeffr13]

Adding tank valve weight and heavier fins will just counteract each other.

Adding tank valve weight and heavier fins will just counteract each other.

I did notice in the pool that 1lb ankle weights did help keep my feet down better on time trying. The instructor had me use them to keep my feet from flipping me too much while doing test. He stated because of the back inflated BCD was doing that. My fins are positive buoyant(float). I don't think that just adding the heavier fins will fix the upper body/tank buoyancy. I can make myself trim line with my head/upper body movement downward and bringing my hands and arm down and under me. Its how I move around with just breaths in/out to go up/down. I just want to make it easier to trim line dive and relax better when I can. If I can make myself more trim line with less effort then maybe the fins and kicking will be a none issue.

 

[johndiver999]

Diving with a full 7 mm suit with hood and boots etc. is far different than the feel in a pool. The suit compression is significant and if you are diving relatively shallow, you will need to make frequent adjustments to the BC. It is difficult to attain perfect trim if you are going from a bathing suit in a pool to a 7 mm suit in open water and if you are using steel versus aluminum tanks, this adds another significant variable.

I would definitely be using a weight belt with a 7 mm suit and probably have a minimum of 10-12 lbs, in the ocean maybe 16 or so.

 

[saxman242]

I did notice in the pool that 1lb ankle weights did help keep my feet down better on time trying. The instructor had me use them to keep my feet from flipping me too much while doing test. He stated because of the back inflated BCD was doing that. My fins are positive buoyant(float). I don't think that just adding the heavier fins will fix the upper body/tank buoyancy. I can make myself trim line with my head/upper body movement downward and bringing my hands and arm down and under me. Its how I move around with just breaths in/out to go up/down. I just want to make it easier to trim line dive and relax better when I can. If I can make myself more trim line with less effort then maybe the fins and kicking will be a none issue.

Two questions:

When you're underwater doing your best skydiver impression and try to move your hands/arms "down and under you", where do you put them?

If you're horizontal underwater and completely relax without trying to hold your position, do you stay horizontal, end up vertical with your head up, or end up vertical upside down with your feet above you?

 

[Jeffr13]

Two questions:

When you're underwater doing your best skydiver impression and try to move your hands/arms "down and under you", where do you put them?

If you're horizontal underwater and completely relax without trying to hold your position, do you stay horizontal, end up vertical with your head up, or end up vertical upside down with your feet above you?

Both feet and head/upper body goes up, like in the skydiver position. I have to fit both positions. This has been pretty constant for at least 6 dives. I can say they only time less of problem is toward in of dives with less air and/or close to surface.

 

[tursiops]

Both feet and head/upper body goes up, like in the skydiver position. I have to fit both positions. This has been pretty constant for at least 6 dives. I can say they only time less of problem is toward in of dives with less air and/or close to surface.

If you could spend a moment to edit your post it will be easier to understand what you are saying.

 

[saxman242]

Both feet and head/upper body goes up, like in the skydiver position. I have to fit both positions. This has been pretty constant for at least 6 dives. I can say they only time less of problem is toward in of dives with less air and/or close to surface.

Can you describe the position you're trying to get in/how what you're in differs from that?