Looking for 'Balanced' BP/W weight distribution advice

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Thunter96

Registered
Messages
9
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Location
SoCal
# of dives
25 - 49
So my wife wants to know what dive gear I'd like for Xmas, and the biggest gripe I have with my current setup is my weight belt. I wear 20#s on a simple webbing belt over my harness crotch strap. I loosens and slides down my hips, and is hard to properly position when putting it on in the water. Long story short its unwieldy and uncomfortable. Also god forbid I ever had to ditch it below the surface, its all or nothing and I would rocket up. I was thinking of slapping two ditchable weight pockets on my webbing harness, but while shopping around I've decided that may not really be ideal.

I dive recreationally(~120ft max depth) in SoCal(saltwater only) with a 7mm FJ wetsuit, 6# SS BP/W, 35# wing, single AL-80 and 20#'s of lead on a weight belt.

In addition to what I stated above, I assumed:
-Rental AL-80's are +4# empty, -1# full.
-Buoyancy of reg(-?#) and empty wing/harness(+?#) assumed close to 0#s.
-I'm probably around +4#s buoyant(based on snorkeling)
-That would mean my wetsuit is about 18#s buoyant on the surface.
-At depth my wetsuit would lose about 80% of its buoyancy(-14.5#s)

In my mind, a good balanced rig would have the following:
-Neutral at end of dive(duh)
-Rig comfortably floats itself
-W/o rig, I float with minimum 10#s of buoyancy to keep my head up
-Weight is worn comfortably.
-I don't need to remove weight belt to take off rig.
-At depth, with weights ditched buoyancy is around -8#s(not impossible to swim up with a total wing failure, but won't rocket up the entire way)

Given the 19.5# buoyancy swing(air consumption+wetsuit compression) over the course of the dive, that would indicate I should keep a minimum of 11#s of weight easily ditch-able.

Adding all 20#s of lead to the BP/W harness would make it very heavy/unwieldy, and it wouldn't have a very large floatation margin at surface.

So I'm considering the following options:
A weight belt with 12#s in ditchable weight pouches, worn under the crotch strap(possibly with suspenders), and 6#s on my rig(likely trim pockets on cam bands).
Pros:
+Trim weights can be moved around easily
+More comfortable (suspenders on weight belt could be used, rig is not super heavy)
Cons:
- Only #10 buoyancy without rig at surface(seems a little sketchy)

OR: A weight belt under the crotch strap with 6-8#s(not easily ditchable) and 12-14#s in ditchable pouches on my rig.
Pros:
+14-16#s buoyancy without rig at surface
Cons:
-Doesn't sound more comfortable(all weight still worn around hips, heavy rig).
-No movable trim weights.

I already have 2x 7# and 3# weights, so leaning towards something that utilizes them, but also not looking to spend a ton of money. Will likely always be diving wet and with rental AL80's.

The question buried in here is am I on the right track here of just nuts? Do my assumptions/goals seem appropriate? How should I try to make my weighting system more balanced without making it complicated? How have you weighted yourself when using a really buoyant wetsuit?
 
For context, I dive a 20/10 FJ or a 15/5. When I was diving single tank, it was AL80, SS plate, 30lb wing, crotch strap, long hose. So this ground is familiar to me, though I have not traced through your numbers exactly.

You do not need all your weight dichable. Definitely put some weight on the rig. To me, put it high up, as that usually helps trim. I'd focus on the belt being your quick ditchable. With the belt holding 10 lbs or so you are out of the missile territory.

Belt under and weight quickly ditchable on rig usually means both sets of weights are very close together, that means trim likely sucks and they get in each other's way for height real-estate on the body. Some do the suspenders and ditchable, it seems bulky to me. Another option is some of the smaller ditch pockets added to a standard belt worn under, but I'm not sure how well that fits. Basically a smaller capacity and bulk version of the suspenders. I think the cleanest for rec diving is a modest belt over the crotch and the remaining weight higher up on the rig.

You can easily remove the rig from under the weight belt if you remove the front and possibly rear D from the crotch. You just pull the crotch free in front then back. I have Ds on the hip belt at the plate for the gear that would be on the rear D. Rethreading the crotch under the belt at depth is more of a pain, but simple with those Ds gone. If you actually needed them, it is all harder.

I'm not sure you need to be super buoyant on the surface. If you need to you can always ditch the weight belt.

Trim weights are great. SubGravity makes nice trim weight pockets. One on each shoulder strap gives you one to three pounds per side higher for trim, more than that is uncomfortable. On the shoulders, they are also slowly ditchable if you are horizontal or inverted.

Reg plus harness hardware is likely two pounds.

A skin diver's rubber weight belt should solve the belt slipping problem and be more comfortable. They have been on my list to try. Though trimming that down to the 10-pound range should solve that.

I find 3# and 1# flat weights most useful. I do not really use the slots but they are fine. With an interest in trim, 7# is way too much in one place to be helpful. But my weight belt has two pockets on each side, so I can build up whatever I need easily.

For weight on the rig, you can also zip tie and gorilla tape two one pound solid ingot weights up by the shoulders to the side of the tank. You can also put two to three 1lb solid ingots of lead in the plate channel. Lead Mini Ingot Pure 99.9% ~ 1 Pound-Mix sizes I would coat them first.
 
Bolt some lead on

full.jpg


man
 
Getting 20# off your waist is not to hard. Put four trim pockets, two on each cam band, as close to the wing as possible. I would take two 4# and two 3# off your belt and put them in your pockets. You can move them around until you find your trim. The remaining 6# can stay on a belt if you want ditchable weights, two #3s or three 2#s. But six lbs is much more comfortable than twenty lbs on the waist. As you get more comfortable you might even consider moving additional weigh off the belt into the trim pockets.
 
Thanks all, especially Michael, that was pretty helpful.

I think I'll get a freediver rubber weight belt, and put either 8 or 10#s on it. The rest I'll mount to by BP somehow.

I have a used DSS plate, so I would love to find some of those plate weight kits or a compatible P weight(with say 4#s left over as easily adjustable trim), but for now will look at smaller weights to either bolt to the plate or put on the cam bands. My wing has a built in STA, so adding a weighted STA is a nogo.

8-10#s will probably be fairly comfortable and manageable on a weight belt, and 10#-2#s added to the BP rig won't make it crazy heavy. Some of the diving I do is from a small inflatable boat, and being able don everything in the water easily makes a big difference, hence the reason why I would like to be plenty buoyant at the surface without the rig but possibly wearing the weight belt, obviously keeping the weight belt over the harness means it'll have to go in the water after the BP/W, unless I add ditchable pockets to the belt and wear it under.

Michael(oldbear),
Pretty cool to see someone from Kwaj comment, my dad lived out there for several years and has lots of stories and fond memories from there, both diving related and not. It sounds like a really unique place only a few will get to experience.
 
I think you are on the right track with trying a freedive belt with a modest amount of lead on it. 10 or 12 lbs should be comfortable and manageable.

I used to feel the same way about having the weightbelt over the harness and crotch strap. However, you can get used to opening the waist strap of the harness, freeing the crotch strap and then removing the weightbelt before existing the water, It is always nice to remove the weightbelt first, then hand up or clip off the scuba unit, before hopping out of the water.

Also, it will be sooo much easier if you are diving from an inflatable and doning your scuba gear in the water IF you have put your weightbelt on before going in the water. If your weightbelt is modest, then there should be no issue with floating with a weightbelt and wetsuit and no scuba unit.
 
In addition to what others have said. I found a harness better than any weight belt even the rubber ones. I have no hips so no matter any belt slid down and was hanging off my crotch strap at 15 feet.
 
I was wondering if you could explain how your wetsuit would lose 80% of its bouyancy at 120 feet?
120 feet divided by 33 equals roughly 4 Ata of pressure. Add other ata from the surface means that total pressure is 5 Ata. 1/5 =20% of start thickness which is an 80% loss of buoyancy. All this is from Boyles law
 
https://www.shearwater.com/products/swift/

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