Balancing wetsuit and steel tank bouyancies

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!

FishDiver

Contributor
Messages
749
Reaction score
10
Location
Davis, CA
# of dives
1000 - 2499
I am putting together a matrix for balancing different size steel tanks with various wetsuit thickness for scuba travel. A common configuration for hundreds of my dives was a 5 mm suit, 8# plate, 2# lead and a steel 100 cf tank. I now have a 2# travel plate that I have used with a 3 mm suit and a 100 cf tank although it was a few pounds negative. I have also used my 8# plate with a 7 mm semi and a steel 120 cf with 8-10# of lead.

Aside from the "no steel with wetsuits dogma" are there any common configurations or rules of thumb for tank size vs suit thickness?
 

FishDiver

Contributor
Messages
749
Reaction score
10
Location
Davis, CA
# of dives
1000 - 2499
I have my buoyancy nailed in the DS. I am putting together sanity checks for travel gear configs.
 

TSandM

Missed and loved by many.
Rest in Peace
ScubaBoard Supporter
Messages
36,349
Reaction score
13,637
Location
Woodinville, WA
I travel with my dry suit . . . I don't know exactly what you are trying to do, but if you take three people in three different brands of 3 mil wetsuit, of different ages, and different sizes, their buoyancy could vary by several pounds.
 

50Fathom

Contributor
Messages
308
Reaction score
194
Location
Central Texas
# of dives
200 - 499
I know a diver who is so morbidly obese, they can dive double HP120s in a 3mm wetsuit in freshwater and not be "unbalanced". Physiology definitely plays a role.
 

FishDiver

Contributor
Messages
749
Reaction score
10
Location
Davis, CA
# of dives
1000 - 2499
Good points all. I should have asked a more specific question set. Anyone know the average buoyancies of say a size large wetsuit in 3, 5, and 7 mm thickness? I can look up tank characteristics separately and make my own calculations. I own a heavy compressed neoprene drysuit that is a major hassle to fly with. Typically, I travel to the tropics where the temps and dive lengths dictate a wetsuit.
 

rjack321

ScubaBoard Supporter
ScubaBoard Supporter
Messages
11,455
Reaction score
6,345
Location
Port Orchard, Washington State
# of dives
1000 - 2499
You have everything you need math-wise right here:

5 mm suit, 8# plate, 2# lead and a steel 100 cf tank.
steel 100 is -1 empty so your 5mm suit = +9

I now have a 2# travel plate that I have used with a 3 mm suit and a 100 cf tank although it was a few pounds negative.
-1 for empty 100cf tank again plus -2 for light plate and still negative? 3mm suit on you is neutral or +1

I have also used my 8# plate with a 7 mm semi and a steel 120 cf with 8-10# of lead.
steel 120 is -2 empty plus -8 for plate and (average) -9 for lead = your 7mm suit on you is +19


so your...
3mm suit = neutral (for you, it floats but you sink a little)
5mm suit = +9
7mm suit = +19

Other suits and other divers are likely to reach different numbers. But you should be able to figure out how much lead you need for an AL80 tank and 5mm suit for instance.
 

FishDiver

Contributor
Messages
749
Reaction score
10
Location
Davis, CA
# of dives
1000 - 2499
You have everything you need math-wise right here:

steel 100 is -1 empty so your 5mm suit = +9

-1 for empty 100cf tank again plus -2 for light plate and still negative? 3mm suit on you is neutral or +1

steel 120 is -2 empty plus -8 for plate and (average) -9 for lead = your 7mm suit on you is +19


so your...
3mm suit = neutral (for you, it floats but you sink a little)
5mm suit = +9
7mm suit = +19

Other suits and other divers are likely to reach different numbers. But you should be able to figure out how much lead you need for an AL80 tank and 5mm suit for instance.

Brilliant! Thanks for doing my homework.
 
https://www.shearwater.com/products/peregrine/
http://cavediveflorida.com/Rum_House.htm

Top Bottom