How to guess a starting point for weight?

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

dmentia

Guest
Messages
65
Reaction score
0
Location
Winthrop Harbor, Illinois
Hello all,
As a newbie, I am wondering if there is a "rule" for weights as a starting point. I am going to do some warm water diving (lycra suit only) in 3 weeks, and then most my diving will be in a 6 or 7mm wetsuit in Illinois/Wisconsin. I have all my gear except a wetsuit and weights. My BC is weight intergrated, so changing weight will be easy, but I don't want to go out and buy a ton of weights I won't need...
Thanks!
dmentia
 
Dmentia, welcome to the boards, we're glad to have you here. When diving with a Lycra, depending on what type of body composition you have and what type of cylinder you will be using, you shouldn't need any more than a few pounds of weight. Just remember to do you buoyancy checks with an near empty cylinder or compensate for it so that you can do a comfortable safety stop towards the end of your dive.

As for the 6.5-7mm range, we always start with a starting point of 10% of your body weight plus 4-6 pounds. Again, there are always exceptions to the rule, just use it as a starting point.
 
that 10% rule does work I put on 32 pounds of weight I weigh 280, factored in wetsuit ect.. got in the pool and thought myself still light.. during the class there was this buoyency check where you try to float at eye level with an empty BC and full lungs.. after adjustingsinking way fast several times I now carry 14 pounds plus two around my ankles, legs float too much. The PADI offers a bouyency class that I'm getting ready to take which my instructors say will help even more..
 
It mostly depends on your tanks.. Using 1 aluminum 80 will be different weight needs than using double steel 95's..
 
The 10%+ rule generally seems to work when wearing thicker wetsuits, although for larger folks, sometimes the "+" tends to be more like 5-10 pounds.

As already mentioned above, there are many variables that affect your weight in addition to wetsuit and body type. Tank buoyancy plays a role here as well -- in general, steel tanks are negatively buoyant when full (and neutral or slight negative when empty), Aluminum tanks are neutral to slight positive when full (and more positive when empty).

Salt Water vs. Fresh Water -- Salt water is more buoyant = more weight.

Finally, "newbieness" also affects buoyancy. I am still a newbie (25 dives) -- as I've become more relaxed while I dive, I've been able to shed some weight.

Bottom line, it takes some experimentation to master buoyancy and weighting. Good luck and safe diving!
 
:bounce:

Welcome to the boards. The 10% rule is ok, but I find the best way to weight yourself is to get into your kit and take a weight belt with 2 and 4 pounders on it (all done in a pool) and keep removing weight until you are just right. Make sure you do it w. 500 psi in the tanks. That way you know for sure that with more gas you will be fine.

Hope this helps,

Eric
 
I just think it bears repeating to make sure you do a bouyancy check with ALL the exposure protection that you are planning to use for that particular dive. Eg: hood & gloves & full 1/4" suit is a lot different than 1/8" or less tropical suit.

And again, the type of cylinder is also a factor. Aluminum tanks tend to get more bouyant as they empty, while steel tanks are always negative, even with litte air in them.

BTW, welcome to diving... awesome, ain't it?! :)

~SubMariner~
 
I too agree with Submariner in that there are plenty of great answers here. Body composition and cylinder choice also effects the amount of lead you will need along with beleive it or not... experience in the water as well.

When diving here in SoCal, I use a 7mm Oneill full suit with 3mm gloves and 6.5 mm booties. At 197 pounds of body weight I should need more weight than I dive with... When diving with my LP steel 95 cylinder I use 6 pounds of weight. When diving with an Al80 I use 12 pounds of weight.

The point I'm trying to make is to do a proper buoyancy check with all of your gear on. You should have all exposure protection gear donned, a cylinder with 300-500 psi of air in it and do your buoyancy check from there. Everyone's weighting needs are going to be different. Often times an instructor can help you dial in your requirement more efficiently than you could on your own. Ask your instructor, or an instructor for help. Any number of us would be happy to give you a hand.
 

Back
Top Bottom