"Gold Standard" weight check

[inquis]

15 lbs for my one-piece 7mm. Two piece suits will likely be 20 ish.

 

[inquis]

so let me get this straight. Diver whips out their DSMB

No, it's during the stop that it's a potential issue. Most people don't use a heavy reel, so they have to hang on the line a bit to get it to stand up. If the "ideal" weight makes you neutral at the stop, its difficult to do that.

Carrying a bit extra to avoid corking a thicker suit should give enough to hang on the line at 15 ft. The warm water diver, however might need a little more than they consider ideal without a DSMB.

 

[PeterMc]

• The diver should have just enough weight to be neutrally buoyant with empty tanks and an empty wing.

Would anyone disagree?

My disagreement with this would be if you are diving in the open ocean and there are swells above, those swells will most likely start to bring you to the surface if you don't have additional weight holding you down during the swells.

 

[Eric Sedletzky]

My disagreement with this would be if you are diving in the open ocean and there are swells above, those swells will most likely start to bring you to the surface if you don't have additional weight holding you down during the swells.

Yes, but having any air in your wing also means it will expand and compress at just a few feet of depth difference making holding a stop difficult. If the wing is empty that is one less air space that can expand and contract right at the 15’ depth that is the most sensitive to pressure changes.

 

[johndiver999]

Yes, but having any air in your wing also means it will expand and compress at just a few feet of depth difference making holding a stop difficult. If the wing is empty that is one less air space that can expand and contract right at the 15’ depth that is the most sensitive to pressure changes.

Yeah and if you are heavy and hanging down from a string on the smb, you will remain negative regardless of small variations in depth, assuming you have enough lead. So there is little or no difficulty.

 

[wetb4igetinthewater]

Yes, but having any air in your wing also means it will expand and compress at just a few feet of depth difference making holding a stop difficult. If the wing is empty that is one less air space that can expand and contract right at the 15’ depth that is the most sensitive to pressure changes.

Yeah and if you are heavy and hanging down from a string on the smb, you will remain negative regardless of small variations in depth, assuming you have enough lead. So there is little or no difficulty.

For ocean diving (well Puget Sound, Strait of Juan de Fuca), I just take a 2-lb'er for my DSMB. That's enough to let it hang while keeping a 6' long Halcyon DSMB pointing out of the water to some degree.

For that diving with swells (I check the wind forecast), I'm not draining my cylinders down to 500 psi either.

 

[PeterMc]

Yes, but having any air in your wing also means it will expand and compress at just a few feet of depth difference making holding a stop difficult. If the wing is empty that is one less air space that can expand and contract right at the 15’ depth that is the most sensitive to pressure changes.

That is true, but I'd use my lungs to negate that effect. If I need to descend, being a little heavy I could exhale and go down (note, I said I little heavy, not overweight). Vs if perfectly neutrally buoyant, it would be a little tougher to get down during the swell up. But then again, I like being a little heavy, you can neutralize extra weight with buoyancy in the water, but you cannot negate extra buoyancy in the water without assistance.

Or maybe that's another question - neutrally buoyant at 15' (or 20') empty bladder and empty tank - with lungs full? or lungs empty?

 

[wetb4igetinthewater]

neutrally buoyant at 15' (or 20') empty bladder and empty tank - with lungs full? or lungs empty?

Breathing normally, rising and falling with your breath.

 

[rx7diver]

I've been writing some blog posts about diving, and just wrote this one about correct weighting. I'd love to hear everyone's thoughts, either about the concept or the writing.

https://firstprinciplesdiving.com/the-gold-standard-weight-check/

(If self promoting blog posts isn't allowed here, please delete.)

How one might determine his/her "correct" weight differs depending on the gear he/she is wearing, among other things, I think. That's what makes these prescriptions/recipes a bit difficult.

rx7diver

 

[inquis]

I target weight checks at the end of a normal exhale. It's repeatable and leaves room to reduce or increase buoyancy if necessary.