Adjusting BCD position for trim control?

[Sirto]

I just got back from a dive trip in which I found that my feet dropped whenever I stopped finning. I have raised the tank as high as I can and move 4# onto the tank strap. I put 6# in the rear trim pockets which are located low on the BCD.

I was just reading other posts about this problem and they mostly dealt with moving the weights and the tank as I already did and the thought occured to me that I could lengthen the shoulder straps on the BCD and wear it a little lower so the the bouyant force would move down. Does this make sense?

I am wearing a 3mm shorty with an AL80 and using 24#. I could probably drop a couple of pounds but could not get down when using only 20# during my initial weighting tests on this last trip (I'm quite bouyant unfortunately ).

 

[jbisjim]

Try Using a weight harness and/or trim weights on your tank band. Those can move more of your weights up a bit. And do more than moving the tank.

I have seen this work for several people.

 

[jbd]

I just got back from a dive trip in which I found that my feet dropped whenever I stopped finning. I have raised the tank as high as I can and move 4# onto the tank strap. I put 6# in the rear trim pockets which are located low on the BCD.

I was just reading other posts about this problem and they mostly dealt with moving the weights and the tank as I already did and the thought occured to me that I could lengthen the shoulder straps on the BCD and wear it a little lower so the the bouyant force would move down. Does this make sense?

I am wearing a 3mm shorty with an AL80 and using 24#. I could probably drop a couple of pounds but could not get down when using only 20# during my initial weighting tests on this last trip (I'm quite bouyant unfortunately ).

Are you using a weight intergrated BC? If not try moving the weight belt up on your body once you descend. You can also bend you legs at the knees and use either a modified flutter of a frog kick.

Not sure how often you dive but the more frequently you dive the more relaxed you will become and you should be able to get under 20 lbs.

 

[ShakaZulu]

No wonder, with that amount of weight I'm surprized you don't just sink to the bottom...........I use 24lbs (with an AL80) and I have a 7mm suit, with hooded vest, gloves and boots. Drop at least six pounds and try again (let all the air out of your BC, exhale and stop kicking on descend, you'll be fine).

 

[jbd]

No wonder, with that amount of weight I'm surprized you don't just sink to the bottom...........I use 24lbs (with an AL80) and I have a 7mm suit, with hooded vest, gloves and boots. Drop at least six pounds and try again (let all the air out of your BC, exhale and stop kicking on descend, you'll be fine).

Shaka.....recheck the last part that Sirto put in parenthesis.

I worked with a person who floated like a cork with 14 lbs on a weight belt just wearing a swim suit.

 

[ShakaZulu]

Shaka.....recheck the last part that Sirto put in parenthesis.

I worked with a person who floated like a cork with 14 lbs on a weight belt just wearing a swim suit.

Wow, hard to believe, Sirto, redo your boyency tests. Empty 500psi tank, figure out how much weight you need. Will make a huge difference in your diving experience. We have no info on your physical attributes.......

 

[neil]

I was just reading other posts about this problem and they mostly dealt with moving the weights and the tank as I already did and the thought occured to me that I could lengthen the shoulder straps on the BCD and wear it a little lower so the the bouyant force would move down. Does this make sense?

Yes, it makes sense but you aren't going to get much result from that little bit of movement of the BC, IMO. Assuming your overall weighting is correct, put MORE weight up high on the tank or the trim pockets on your BC. Remember to keep the tank weights tucked in close to the BC. I have more than half my lead in the trim pockets or tank weights. If you think that's a lot, consider someone using a large steel backplate (which is something like 9 or 10 lbs. negative) and then adding trim weights.

 

[Sirto]

Yes, it makes sense but you aren't going to get much result from that little bit of movement of the BC, IMO. Assuming your overall weighting is correct, put MORE weight up high on the tank or the trim pockets on your BC. Remember to keep the tank weights tucked in close to the BC. I have more than half my lead in the trim pockets or tank weights. If you think that's a lot, consider someone using a large steel backplate (which is something like 9 or 10 lbs. negative) and then adding trim weights.

I had a 4# weight on my tank strap. I can change that to a 5# weight but to add any more would require a second weight and might interfere with the function of the strap. Would it be ok to add two weights on the strap? Alternately, can I use a weight belt to strap a weight on the tank. (Sorry if that's a stupid question).

The trim pockets are low on the back of the BCD, not much higher than the integrated weight pockets so moving more weight from the weight pockets to the trim pockets probably won't have too much of an effect. I will however transfer a couple of more pounds to the trim pockets. Every little bit helps.

On my next trip I'll try hard to drop some of the lead as well.

 

[MyDiveLog]

Shaka.....recheck the last part that Sirto put in parenthesis.

I worked with a person who floated like a cork with 14 lbs on a weight belt just wearing a swim suit.

Sounds to me like Sirto is over-weighted. I'm 6'3 and 205# and dive with 12 lbs when I use my 3 mil in warm water. I use 20# when diving with my 7 mil here in CA (used to use 23 when I weighted 235) and I'm no special physical specimen. I've worked with some .... very large ... students, and NONE have required more than 4 lbs to sink in a swim suit. Most students don't require any weight to do so. I'll bet that the student requiring 14 lbs as 2) abnormally large and b)holding a LOT of air in their lungs.

 

[Michael Schlink]

I would like to suggest the following
1st. Determine the PROPER amounrt of weight you need.
2nd. Distribute your total weight load in the best places for balance and trim
IE. Move some weight higher up towards your head but if you try to load too much weight on the tank strap you may find it will try to roll you over like a sailboat keel. Try to place the weight as close to your back as possible.
Be sure that you can "ditch" enough weight so that in an emergency you can float on the surface, you do not need to ditch enough weight that you are "rocketing" to the surface.
3rd. Try bending your legs at the knees to utilize a frog kick that a lot of us use all the time
4th. PRACTICE- if your only problem is your feet are dropping you're doing great Practice and experience will give you the ability to position yourself as needed, head up, head down, feet up, feet down, whatever