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Vercingetorix
09-07-2007, 13:24
Perhaps this thread belongs in the Training forum.

I know that some folks have trouble with their feet rising. I have the opposite problem, they sink. I cannot maintain a horizontal hover without constantly finning. Of course, that propels me forward. This is not good when trying to photograph or hovering along a wall.

The particulars: I'm 5'11", 180 pounds. I dive with a BP/W (BP is SS). My tank is a neutral buoyancy aluminum 80 cf. When diving fresh water, I wear NO weights with a 3mm wetsuit and 16 pounds of lead in 7mm fj suit. My fins are Aeris Velocity hybrid. My booties are 5mm full boot (not shorties)

I have the problem regardless of whether I'm diving with no wetsuit, a 3mm or 7mm fj. My tank is a far forward as I can make it without smacking the back of my head against the first stage.

I've tried various things I learned in PPB. I cannot move weights because, to repeat, I'm not wearing a weight belt nor do I have integrated weighting in my BP/W.

I know there are ankle weights for floaty feet; is there something similar for sinking feet? I really like my Velocity fins, but I may need to give-up on those for a lighter fin, if there is such a thing. That is a last resort, though.

Suggestions?

Osprey
09-07-2007, 13:28
I sure as hell thought that said "My feet STINK"!!!

No suggestions except I need to learn to read

No Misses
09-07-2007, 13:35
When you are diving the 7m suit, you mentioned carrying 16lbs. Try moving some of these to the uper half of the backlate. You can use a cable tie to hold a solid weight to the "tank side" of the backplate, between the plate and the wing. I would try 2 or 4 lbs out of the 16 that you are carrying. when you dive with no weights (fresh water) you may need to add a couple of weights to the BP. These are the cheap options. Next up in cost would be an AL BP. That way you can add weights to the plate where you need them. The last option (most costly) is switch to steel 100 tanks. They are shorter than AL 80. You can put more wieght forward (up). Let us know how it goes. good luck.

No Misses
09-07-2007, 13:36
I sure as hell thought that said "My feet STINK"!!!

No suggestions except I need to learn to read

Osprey I also read "My Feet Stink" I was going to post a wise crack about if your feet smell and your nose runs, you're upside down.

Disneymom
09-07-2007, 13:37
Osprey - that's what I read too.....

sorry, Rick.


How buoyant are your fins? Aren't some more buoyant than others? Can you get 7 mil booties?

Vercingetorix
09-07-2007, 13:46
I sure as hell thought that said "My feet STINK"!!!

No suggestions except I need to learn to readI purposely chose the phrase to see if I could catch anybody. GOTCHA!!!!

No_Misses: I do have an aluminum plate that I've not used. I'll try that. I also like your idea of zip-tying a couple pounds to the top of the BP. I may even try 2 pounds regardless of my wetsuit. Yeah, I'll be a bit overweighted (when wearing 3mm), but then my wing has 35# of lift (GolemGear). My wife told me specifically: Do Not Buy A Tank!! Like a good boy, I bought one anyway. If I bought a second, well...I might have to take up permanent residence at the ScubaToys location.

ReefHound
09-07-2007, 13:50
I'm in the same boat and I think most people in a wetsuit will have heavy feet. Bone and muscle are denser than water, and there are no air pockets in the feet.

It all comes down to balance, your center of gravity is somewhere near your lower back and the buoyancy north of that must be equal to the buoyancy south of that. Since you have these big air pockets called "lungs" north of that you need lots of weight north of that to offset.

There's another thread here, hate to say go search but I don't recall the title and it had comprehensive info (pasted from GUE, I believe).

A few notes, the N80 tanks are heavier at the bottom, try a standard 80 and see if that helps. If you use a SS plate, try a AL plate and add bolt-on weights to the top of the plate. Keep your face down, your back arched, and your knees bent.

I haven't seen them but I wonder if someone makes neoprene wraps for the lower legs? Similar to drysuit gaiters but designed to add a pound or so.

If all else fails, learn to fin backwards. You can alternate foreward and backward strokes to stay in place.

Osprey
09-07-2007, 13:55
No_Misses- LOL!!

And Rick, I owe you an angry fist shake for snagging me in that trap!

*angry fist shake*

Vercingetorix
09-07-2007, 14:48
ReefHound, thanks for the heads-up about the article. I found it. Good info, there. I tried a standard AL80 with the same results. That said, due to the additional buoyancy of AL80, I might be able to move that additional 6 pounds of required lead to the top of the BP.

cummings66
09-07-2007, 19:02
wear NO weights with a 3mm wetsuit and 16 pounds of lead in 7mm fj suit. My fins are Aeris Velocity hybrid. My booties are 5mm full boot (not shorties)

I have the problem regardless of whether I'm diving with no wetsuit, a 3mm or 7mm fj. My tank is a far forward as I can make it without smacking the back of my head against the first stage.


I'd also say don't worry about smacking your head. My valves are such that I can touch them to the back of my head if I arch it backwards, it doesn't affect my diving however and it's enough to make me neutral in trim.

I'm guessing you're placing the weight in the V channel since you say you don't have a weight belt? If not then try that.

When I used to dive with a traditional jacket bc I made a custom weight that wrapped the top of my tank up by the valve, sand casting method. It worked and got the trim right.

The solution is simple, you know in a 7mm FJ you need 16 lbs of lead to stay neutral. Next dive have your buddy place the weights on top of you at different spots and see where they are to trim you out. IMO bend your knee's upwards like you're doing a frog kick when you trim out. Also stick your hands out in front of you if need be.

scuba Widow
09-07-2007, 19:11
I sure as hell thought that said "My feet STINK"!!!

No suggestions except I need to learn to read

Don't feel bad I did too:smilie39:

Black-Gorrilla
09-07-2007, 19:18
tie some foam around your ankles.... level u right off!

divechaplain-sara
09-07-2007, 19:39
I misread that title and thought you said that your feet stink. I was going to have to say mine too. I haven't had a problem with the feet sinking thing. Some extra neoprene might make a difference for you. I did my openwater check out dives in a 7 mil suit and couldn't do a fin pivot because my feet floated. I had to do the pivot on my knees like doing a girls push up.

mm_dm
09-07-2007, 19:39
I was going to say try letting some of the air out of your head, but you're cool and I don't want to peeve you. If you go to the aluminum plate, try putting some of those ankle weights around the k-valve on the tank. You can snap them right around the valve neck and the reg helps keep them in place. They're the kind that many drysuit divers use.

cummings66
09-07-2007, 22:05
The key is to have the tank as high as you can, then have your weights as high as they can be. I've found for myself that a steel BP really helps place the weight over the lungs. The lungs are the key and the weight needs to be centered there or you will end up with sinking feet.

My feet are very bad about that, I've never needed ankle weights in a drysuit, not even when I first started diving them because my feet were so heavy that it was very tough to dive in trim with a normal BC. I couldn't use a weight belt, or even the trim pockets. I made up things to get the weight up high and that helped.

ertechsg
09-07-2007, 22:31
Why dive a 7 ml? Might as well dive dry theres nothing in CS worth dive that cold

WV Diver
09-08-2007, 06:57
It sounds as though you really just need to get trim. Move your weights around to find that good horizontal position. I picture you moving through the water in a heads up posture and plowing through the water. This is hard on you and your air supply.

You obviously need more of your weight to be placed a little higher than you have it now. A little experimenting will do you proud I'm sure.

You will likely need to change things around more as time goes by and you gain experience and get your buoyancy down really well. Eventually this problem will melt away.

awap
09-08-2007, 07:19
I made a few adjustments to deal with the same problem. I keep my knees bent moving my legs up as close to my body as l comfortably can. I also keep my arms in front of me, hands clasped, where it is easier to see my guages anyway. I also added a couple pounds of weight up high on my BP. I leaves me a bit negative for FW but not too much. Plus my wing (DR travel wing) is fatter on the bottom which puts the lift down arounbd my waist when I am properly trimmed. If I use my SP Mk7 1st stage which weighs a couple pounds, I don't even notice the heavy legs.

I only have the problem when diving little or no neoprene. No problem if I am using my 5mm which puts uncompensated bouyancy at my legs and about 6 lb in a belt.

Zyxistal
09-08-2007, 14:13
If all else fails you invent your very own line of products for people with this problem, patent it, and then sell have ScubaToys sell it. Its a win/win/win deal.

Charles R
09-08-2007, 14:48
I think this thread will win because everyone thought you feet stink that is what I still read everytime I see it pop up and Ive read the whole thread.

awap
09-08-2007, 15:25
One solution that will help regardless of how the tittle is read: fill your nose with lead weights.

Vercingetorix
09-08-2007, 16:50
Thanks for all the suggestions so far. They've given me some ideas to try.

Somebody suggested a SS BP and move the tank as high as possible; I already use that (see orig post). I've also tried bending my knees to move center of gravity as forward as possible.

I'm going to see if I can find the weights that attach to the first stage that somebody else mentioned. Meanwhile, I'll definately strap a couple pounds to the top of the BP.

WV Diver is right in that I'm like ths / struggling to get __. This is the problem when hovering, not really when swimming forward. When going forward, I am horizontal.

Somebody else suggested more neoprene: as I mentioned, I'm already wearing 7mil FJ and 5mil full booties. That's about as positive a buoyancy as you can get.

And, for those of you still being caught by the "Feet STINK" versus "Feet SINK"...GOTCHA....

ScubaToys Larry
09-09-2007, 19:26
The fastest and easiest... and I've seen this done a lot is get a set of ankle weights.

I know... you're saying... that's not the problem... me feet sink - not float... Yea, take the ankle weight, tighten it up, and clip it around the tank valve. If one is not enough... go for 2. I had a friend in Cayman that was an awesome diver, and always dove with a tank weight clipped around the tank valve for the very reason you describe.

Vercingetorix
09-09-2007, 19:42
Larry, thank you. I guess I've another trip to ScubaToys in the offing before next Sunday (I'm helping Mac with the Rescue class).

Vercingetorix
09-17-2007, 11:51
Just finished at CSSP this past weekend. I tried a couple things.

1) Moved my tank (AL neutral buoyancy) higher about the distance of the width of a tank-strap to put more weight forward.

2) Tried Larry's suggestion about getting more horizontal. In another thread, he mentioned, to paraphrase, "What do you see when you put your chin to your chest?" If you see the bottom, then you are not horizontal. If you see water behind you, then you're good to go.

Both these helped. My feet didn't drop as much while remaining still and I didn't have to fin as much to stay horizontal.. I may move the tank up a bit more. Now, I can REALLY CONCENTRATE on buoyancy control.

Thanks guys

dallasdivergirl
09-17-2007, 13:11
I actually moved my weights around this last weekend & it really helped. Before I had them all in my weight pockets on my hip & I moved half to the back weight pockets. Made a huge difference.

loudgonzo
09-22-2007, 17:18
I moved the trim pockets on my Stiletto from the bottom tank strap to the top strap, will try it out tomorrow at cssp.