Weighting question

[fnfalman]

Thank you for this post. I think this was very helpful and much more realistic than trying to dive with the same amount of weight that I was using with an AL80, when I already felt I was overweighted then. I'm actually going to be diving off a dock, so I'll probably rent ~30 pounds and do a weight check from the dock, adding or taking off as need be.

Thanks,

Kristopher

My pleasure.

The thing about diving the same weight as before or guessing that because you have a steel tank now versus AL80 back then are that:

a. Your current BC is probably different from the other BC, which means different weight requirement.

b. You don't remember which AL80 you used, and as you know now that not all AL80 are the same, as not all steel tanks are the same.

The 10% of body weight plus a few pounds tend to work out pretty well. I have yet to see anybody underweighted with this configuration. And like others have said, you'd want to be overweighted so that you can subtract the weights until you get to a good dive weight.

Log everything in your log book. Log your equipment by manufacturers and models.

Then later on see if you can do a weight check on your BC by letting it soaked with water, empty out the air and throw weight on it until it sinks. You can do the same with your wetsuit as well. Make sure that it's soaked throughout (water logged) then throw weight on it to see how much it takes to sink it. Heck, do a weight check on yourself. Go into the water (obviously not the ocean since that it's cold as hell) of a swimming pool and strap on a weight belt, adjust the weight so that you would float at eye level with a lungful of air.

Remember that when you do weight check in freshwater, add 4-6lbs of lead to it for saltwater compensation.

 

[MauiScubaSteve]

HOWEVER, the data sheet does not include the tank valve, and tank valves are ususally around 2lbs (some are slightly more and some are slightly less, but close enough). That means your tank with valve in place and full with air/gas has the equivalence of wearing 11lbs of lead, and when it's empty has the equivalence of wearing 2lbs of lead.

I think if you look more closely at the asterick's, you will see that the buoyancy numbers do include the valves. If they didn't how would you check the tank full of air?

 

[fnfalman]

I think if you look more closely at the asterick's, you will see that the buoyancy numbers do include the valves. If they didn't how would you check the tank full of air?

Buoyancy numbers can be calculated without having air in place. A certain amount of cubic feet of air is going to weight so much. A tank of a certain material with certain internal dimensions versus external dimensions is going to have so much natural buoyancy.