Ankle floats?

[UCFKnightDiver]

Have you tried saying/telling them "no" when they try to require you to wear the extra three pounds? It makes absolutely no sense to carry more weight than you need to sink/be neutral with an empty tank/500psi, as if you ditched the weight you'd still be negative.

The best way to think about trim is to think of your body in trim as a lever and fulcrum or a seesaw that kids play on. Now ask yourself how can I move weight or buoyancy around on my body closer or further away from my center pivot point/fulcrum to achieve a balance that would put you in horizontal trim. The further away from your center pivot point that weight and/or buoyancy is, the greater effect it will have on your trim. As others have said there's multiple things you can try if your feet are sinking and your head is floating, some of them are:

- Positively buoyant fins or fins that are less negative. This takes away some of the negative buoyancy from your feet and legs as they are already negatively buoyant and sinking.

- Position of the tank on your BCD - more forward/higher or backward/lower. I lean to try it higher, but the @The Chairman point about floaty rear's of aluminum tanks is an interesting one. This shifts the weight of the tank around to find better trim. Think lever and fulcrum/seesaw.

- Different BCD. Maybe an aluminum backplate and wing setup since you don't need more weight. This will get the buoyancy out of the shoulder straps that's making your head float AND put a pound or two of weight over your lungs/upper body which you said was floaty compared to your feet/legs.

- An ankle weight around the TANK NECK. This will add a weight similar to the way you're already doing with putting the 1.5 lb weight in your wetsuit/bra strap. This gets weight further forward to counteract your negative feet/legs. This will add weight that you said you didn't need, though I don't think a pound or two is a big deal. It will not be ditchable either.

- Body position. Get your feet closer to your body, knees bent at 90 degrees. Learn to frog kick from this position. Think of a lever and fulcrum or seesaw, this puts the weight of your feet closer to the fulcrum or pivot point of your body and reduces the effect your heavy legs and feet have on your trim. Also, arch your back and use your back muscles to bring your feet/legs up. Get used to the arched back position/feeling.

- Putting some trim weight up higher on your body, see @The Chairman post on weight on shoulder straps or use trim pockets. Heads up though, this will add more weight that you said you didn't need.

- Someone suggested making gaiters out of an old wetsuit that you would slide around your shins. Problem with this is the neoprene will compress at depth and you will lose some of the buoyancy, but it's an interesting idea.

I'm sure there are others, but I would try some of these ideas that people have given you. As you might have guessed, I'm not a big fan of the ankle floats idea as many materials will compress underwater and lose their buoyancy. If they're inflatable, then you have the same issue of the air compressing and losing buoyancy. Additionally, I don't think there are many options from various manufacturers out there.

Something else to think about regarding the weight is that if you're planning to dive salt water, then you may need to add weight as salt water is more dense and therefore things/people are more buoyant and need more weight to sink. I think you mentioned doing most of this work in a freshwater pool?

That was a bit long winded, but I hope all the information helps. Kudos to you for taking the time and energy to get your trim and buoyancy dialed in! Most people don't devote much time to it and they suffer for it in my opinion.

- Ryan

 

[BlueTrin]

I didn’t insist on this after someone pointed out that you use a small cylinder and also because you were already negative.

But if you have access to one you could try to use a dumpy steel 12 litres cylinder.

They are negative so it will make you even more negative, but you could see if that helps with the trim to have a negative small cylinder on the top of your torso.

You’d be more positive in salt water so you may end up being neutral ?

 

[drk5036]

What kind of water temps are you diving? Could you switch to a 5 mm wetsuit? I doubt you’ll be hot it in, and it’ll fix your overweighting problem!

 

[dmaziuk]

Uhh, about the same.
I used to wear ankle weights in HS training for basketball. Need something that looks like that for ankle floats. Simple thing. Styrophoam? Inflatable?

I've seen styrofoam version of those kids' floats, it's even less streamlined than those inflatable ones. You could just try bubble wrap or the stuff we use for hard disks etc.: Air Column Bag - Protective Airbag Packaging Manufacturer from Ahmedabad. They'll all lose buoyancy with depth, of course, so you're better off with more weight on your neck and an extra puff of air in your BCD.

 

[TMHeimer]

I've seen styrofoam version of those kids' floats, it's even less streamlined than those inflatable ones. You could just try bubble wrap or the stuff we use for hard disks etc.: Air Column Bag - Protective Airbag Packaging Manufacturer from Ahmedabad. They'll all lose buoyancy with depth, of course, so you're better off with more weight on your neck and an extra puff of air in your BCD.

Yes thanks. Must admit, I do keep forgetting about certain things compressing with depth (particularly air). Maybe other than less negative fins or ankle weight around the tank neck (and then removing the equivalent amount from say, the belt) are really the only solutions. Still, would be a challenge for someone to invent a float that wouldn't compress. Maybe air in a noncompressible container (like a boat buoy, but that wraps around your ankle)?

 

[JustWetRocks]

Yes thanks. Must admit, I do keep forgetting about certain things compressing with depth (particularly air). Maybe other than less negative fins or ankle weight around the tank neck (and then removing the equivalent amount from say, the belt) are really the only solutions. Still, would be a challenge for someone to invent a float that wouldn't compress. Maybe air in a noncompressible container (like a boat buoy, but that wraps around your ankle)?

Camera floats?

 

[JustWetRocks]

What kind of water temps are you diving? Could you switch to a 5 mm wetsuit? I doubt you’ll be hot it in, and it’ll fix your overweighting problem!

Typically the water temp is in the 80s unless dropping below the thermocline. Not much Deep to see in the same lake and quarry’s over and over. The more fun stuff is shallow.
If I plan to go deeper I do wear my 7.

This weekend I am planning on not diving with those 3 lbs. I may or may not carry 1.5 in my top to see how that goes. Still need to find some other fins. I will try my splits again and hope for no cramps.

 

[lowviz]

Still, would be a challenge for someone to invent a float that wouldn't compress.

That was job 1 in my long-ago wing constants investigation. Notice upper left. PVC schedule 80 pipes with sealed end caps. Purple primer, sealant, then end-caps. They neutralize a stainless steel frame and balance weights that weigh nearly 100 pounds.

The password is 'wings':


I really don't belong in this forum and shouldn't have posted. However, I couldn't help putting my foot in it due to this being one of my passionate issues with diving.

So, if I were the OP, I'd add two closed PVC cylinders to my BCD on either side of the tank of choice. Those sealed cylinders would be sized to move me into the center of the 'bell curve'. A pint of water is a pound and schedule 80 in the tiny size that the OP needs would be good to a crush depth of much greater than 500 feet. (3:1 safety ratio)

Apologies all.

 

[dmaziuk]

Maybe air in a noncompressible container (like a boat buoy, but that wraps around your ankle)?

Gasoline aka petrol or any other lighter-than-water liquid should work but most of them you wouldn't want to spill. Or take on a plane to your tropical vacation spot. And they tend to have densities in the 0.7 range meaning you'll need a lot to provide enough buoyancy.

Neck Weights For Freediving - DeeperBlue.com

 

[lowwall]

@ScubaCarrie

You don't have a trim problem, you have an instructor problem. There is no logic in requiring you to be overweighted. I would not accept this.

It's possible there is a misunderstanding on the part of the instructor. You do have to have some sort of ditchable weight when it's time to demonstrate that particular skill. Perhaps she is wrongly interpreting that to mean it's required at other times.

If the shop will not budge on their reasoning behind this requirement, I would ask them to verify this with the training office of their certifying agency. If they refuse, I'd do it myself.