NEED ADVICE: In-water ditch/don & weighting in freshwater

[Ready4Launch]

OK. The setup. I'm somewhere just around 200lbs. My setup for diving the coastal California and Channel Islands is with an LP95 while I wear a 7mm suit with a 5/3 hooded vest for 52-58F+ water temps. With the LP95, I'm putting 17lbs of weight into my BC. I have no issues diving this.

Now, that's my regular rec diving setup. Now, I have an organized challenge coming where I must demonstrate certain skills. This is being done in a local high school pool. I have been practicing (trying) to get ready, but I'm having trouble. I'm not sure if it's weighting or technique or just the difference in depth.

I need to do the in-water, full gear removal. It'll be at the bottom of the deep end of the school's pool, which is 20'. I've been practicing (trying to) in my local community pool, where the deep end is 8'.

So, to start this all off, I dropped 5lbs from my regular setup, hopped in the pool, deflated the BC, and exhaled. I dropped below the surface slightly, but bobbed at the surface. OK - 5lbs was too much still. I added 1lb to my BC pocket, repeat, and I slowly sank to the bottom.

"OK - 13lbs seems to be right for my freshwater (pool) setup."

Now, as I sink to the deep end of my 8' community pool, I find that I just can't stay on the bottom. My tank will hit the bottom, but my feet will start to float up!! If I kick up a little to drive my feet down, then I also start to move around as I begin to unbuckle. It starts out all wrong. I mean, I can get to a point where the BC and tank are off my back, but I'm not sitting on the bottom like I need to be and pulling the BC up and over my head, down into my lap, wrapping my legs around with the tank upside down. Instead, I'm floundering through the water, clasping my BC and tank at my chest while face down to the bottom of the pool, and then I pop to the surface of the pool! Once I hit the surface, it seems that I just can't get underwater again.

So ... ! Is this just a matter that the 8' isn't deep enough to keep me down? Should I got to 14 or 15lbs?? (I do not use a weight belt on my body - weight pockets in my Zeagle BC. I don't want to and won't change my setup.) Or, is there some sort of tip/trick that I can or should try to get this done properly? A requirement of the challenge is having to do this at the bottom of the pool. You can't start, pop to the surface, continue breathing through the regulator, and complete the ditch/don. It has to be underwater as I think most will understand is typical for the skill.

I mean, is 13lbs sounding right? I don't see going to 14 or 15lbs helping me much since the problem seems to be how floaty my feet and body get while in the 7/5/3 setup, which also cannot be changed.

Hoping for some insight. Thanks.

 

[Vitesse2l]

If you don't have a weight belt this isn't going to happen how you want. You'll never easily overcome the wetsuit buoyancy.

Why not change your setup just for this challenge? Neutral in your wetsuit with a belt. Or hide a few weight pouches inside your suit...

 

[tbone1004]

@Ready4Launch you are fighting a losing battle. Is it possible? Probably, but trying to do that skill while sitting is going to be incredibly difficult for you.
Here's why.
The easiest way to do this skill is while hovering in a bathing suit. When doing this, your body is essentially neutral, and the rig is neutral. You can undo the waistbelt/crotch strap, go slightly head down and flip it over your head. Very easy to accomplish because everything is neutral.
Slightly harder is sitting while performing the skill, mainly because you have to throw the thing over your head and it's just awkward.

The key with both of those is that the body is neutral and the rig is neutral.
This is going to be harsh, but it is what it is.
What you are trying to do is perform this skill with your body being close to 20lbs positive, and the rig being close to 20lbs negative. If you can't/won't move the weight to a belt, then you are not going to have more success. You mention not being able to sit on the bottom with the tank off, well no sh!t sherlock, you're 20+lbs positive in that suit with nothing holding you down. You then are trying to pull a ~30lb negative brick that is behind you up and over your head. Since you are floating, as you pull on the shoulder straps, it's just going to pick you up.
You are simply setting yourself up for failure by performing this skill. I'm not going to say it can't be done while sitting, but it can't be done gracefully while sitting. The only way to attempt this gracefully IMO is to do it while flat and neutral.

 

[johndiver999]

Hiding lead inside your garments does not sound like an option I would select. If you take weight off the scuba rig and place it on a belt around you body, you will be much more stable. Depending on your exposure protection and inherent bouyancy, the required amount will vary. I would start with 10 lbs on a belt and take 10 lbs off the rig as a first shot

 

[Doby45]

Why are you wearing a wetsuit at all in a pool? Exposure dictates exposure protection. Is this being done in the middle of winter in a frigid pool that you will be in for an extended period of time? Ditch the wetsuit and do the skill in boardshorts and a rash. I do it all the time, easily.

 

[rjack321]

As others have said....
Your suit is all positive
Your BC & tank is all negative
You are going to be a flounding mess if you take the tank off. Take those 13lbs and put them on a belt. Now you are closer to neutral and the BC & tank is closer to neutral (but if the tank is full its still negative.)

Btw since you are at the DM level you should already know you need to be doing weight check with an empty tank not a full one.

 

[Jcp2]

Agree. Since it is demo in pool, maybe a much thinner wetsuit, dive skin, or shorts and t shirt will make things easier.

 

[TMHeimer]

We wore shorties and either 12 or 8 pound soft pellet weightbelts in our 68F (or so) pool. Students doing ditch & don on the bottom was never a problem (I know, the courses should've been taught neutral).

 

[rx7diver]

@Ready4Launch,

My suggestions:

1. Wear only either your wetsuit upper (preferably) or lower, but not both--if you absolutely cannot do the skill without wearing some exposure gear (e.g., if the water is too chilly, as it might be if it is set for a college swim meet). In particular, don't wear your hood, vest, nor gloves/mitts. You'll need your wetsuit booties, too, probably.

2. Get a weight belt and some weights. And weight yourself so that, wearing only skindiving gear (mask & snorkel, booties & fins, and weight belt & weights--and wetsuit upper/lower if necessary), you will be approximately neutrally buoyant at 20 ffw. Do a competent surface dive to get down to depth. Practice descending and then finning around at depth in this skindiving configuration.

3. Get a smaller and more appropriate tank (e.g., an old-school steel 72 or an Al 80, etc.) for this demonstration, rather than your heavy, steel LP95. The tank you use doesn't need to be filled to capacity for this demonstration. Don't use a heavy, steel backplate for this. Don't use integrated weights for this. When you add your fully-assembled scuba rig to your skindiving gear, you might need to adjust the weight on your weight belt slightly.

Okay. That's it. Go practice. You'll be surprised how effortlessly you'll be able to doff and don your scuba at depth--when you're "properly" configured.

One other thing: Make sure the pool lifeguards and safety divers know beforehand what you will be doing. Make sure you inform all of them and get their permission. Otherwise, they might think an emergency is taking place and proceed to "rescue" you.

Safe Diving,

rx7diver

 

[MoistNeoprene]

tbone and others have given you some good advice.

One other factor that I don't think has been mentioned is your breathing. Often times when performing in a stressful situation people have a tendency to breathe less frequently, which results in additional positive buoyancy. So, don't forget to give good full exhalations in addition to the other advice.