Over vs underweighted

[LarryHinDC]

Quote:
"Fresh water is 1.00kg/m3." ----> might be gassy water. Shouldnt it be 1.00 kg/Liter ?

SI unit for density is kg per cubic metre (density is mass/volume).

You're right in that the SI unit for density is kg/m3, but the correct answer is 1000kg/m3, not 1kg/m3. And water does have a mass of 1kg/litre.

Just keepin' it honest!

 

[TMHeimer]

Of course, I agree slightly overweighted is better. And who among us has never had to pick up that rock. I forgot once that I was using my buddy's aluminum 80 and not my steel 120--of course, I had my usual weights. Rock time (very shallow dive). Also, I have been slightly buoyant on 2-3 safety stops. Enough of that. As we know, the tank is always getting lighter as you use up gas (so you add 5 pounds at the start to compensate-so you are now overweight)--so I figure that except for an exact split second during the dive, you are never weighted exactly right. But after a few dives, one finds the right amount and sticks to it, having no problems (unless equipment change, salt to fresh water, gained 20 pounds over Xmas, etc.). Then you say good bye to the days of "Oh, ****, I guess I gotta go back to the car for more weight".

 

[Pullmyfinger]

One I've nailed down exactly how much weight I need I usually round up 2 lbs. I figure, much like the OP that it is better to be overweighted.....
...I define overweight as being no more than 2 lbs over what I've determined to be the exact amount needed.
Buoyancy check with 500psi in the tank is how I determine it for me, although I have read here that there are other methods for establishing how much weight you need.


-Mitch

 

[cowdog77]

"Weighting for neutral on the surface with a near empty tank eliminates that problem."
_____________________________________________
And if novice divers didn't suck their tanks down to 200
they'd have a lot less problems.