New to cold water - overweight?

[tursiops]

I always put around 10 kg (33 pounds right?) on my students

22 lbs, not 33.

 

[Jiminy]

My understanding is that if you do a surface weight check that should get you within 3 lbs, Then you can fine tune with the end of dive buoyancy check

 

[BRT]

My understanding is that if you do a surface weight check that should get you within 3 lbs, Then you can fine tune with the end of dive buoyancy check

5 lb of air in an AL80. If you surface weight check with it full you are light.

 

[Jiminy]

5 lb of air in an AL80. If you surface weight check with it full you are light.

Its just a rule of thumb, my point was its probably preferable to whatever method the instructor is using. Its just a starting point. I think its better than starting 10-14 lbs overweight just because.

Manufacturer Buoyancy Empty, lbs (w/valve)
Luxfer 80 +4.4
Luxfer S80 +2.26
Catalina S80 +4
Catalina C80 - 0.2

 

[rvojr]

Is it salt or fresh water?

 

[BRT]

Its just a rule of thumb, my point was its probably preferable to whatever method the instructor is using. Its just a starting point. I think its better than starting 10-14 lbs overweight just because.

Manufacturer Buoyancy Empty, lbs (w/valve)
Luxfer 80 +4.4
Luxfer S80 +2.26
Catalina S80 +4
Catalina C80 - 0.2

Sure. But you understand that it doesn't matter if the tank is 5 lb negative empty or 5 lb positive empty? Either way an 80 is about 5 lb more negative when filled with air.

 

[Jiminy]

Sure. But you understand that it doesn't matter if the tank is 5 lb negative empty or 5 lb positive empty? Either way an 80 is about 5 lb more negative when filled with air.

I agree with you that the air weighs 5lbs, and i also agree that there will be a swing of 5lbs in total buoyancy when the air is emptied.

 

[Esprise Me]

I just did my first cold water dives yesterday with an instructor. 40ish degree water in a 7mm wetsuit, overalls with jacket. Aluminum 80. I am 5’4” and 140 lbs, very dense, I use 4 lbs in the tropics.

My instructor put 32 pounds of lead on me and insisted I wasn’t overweight, even though I kept crashing to the bottom. He said to use the air in the bcd to stay off the bottom.

This seems wrong to me, but I’m wondering if maybe I’m wrong. I’m also a really experienced diver and he treated me like a brand new student. But I am a brand new cold diver. I just really hate being overweight. I wonder if I can trust someone who intentionally overweighted me? Or maybe I really needed it?

I had a somewhat similar experience recently with a dive guide (also an instructor, but I wasn't taking a course with him) going so far as to literally add weight behind my back. I'm a noob, but I learned to dive in a 7mm and have never needed more than 20 lbs. of lead. Maybe some people need 35 lbs., but it seems like a lot to me, and your experiences seem to confirm it's too much for you. I think you need to at least tell this instructor you're overweighted and insist on figuring out the right amount, and if he's not receptive, don't dive with him. You can try an app or online calculator to ballpark your weight requirements and then fine-tune in the water. I like this one, though I recommend selecting "expert" even if you don't feel like one: DiveBuddy

 

[TMHeimer]

I wear a 7 mil farmer john with AL80 tank and use 42 pounds. Have been told by many that I'm overweight. Also by several instructors that I am fine, and that they use that weight diving wet (heck, they rarely do...).
Do a weight check. There is the simple way that has been mentioned and more sophisticated ways such as weighing all your stuff, etc. It's not rocket science.
Did the instructor you were with not do a proper weight check to confirm what you need? I had to do this for my other two wetsuits for warmer water. Do it for each suit once and write it down. It won't change unless you put 10 years of diving on a thick wetsuit, change equipment (tank, etc.), go from salt to fresh water, or gain/lose a ton of weight. My body weight has varied from 175 to 215 over 14 years and I haven't change my weighting because of that.

 

[grf88]

Wearing a 2 piece Farmer John can be an interesting experience the first time. Most don't realise just how much buoyancy change there can be as you descend and fail to keep up with it to the point they quickly accelerate crashing into the bottom. 14 mm on your core provides a lot of neoprene to compress. You may be a little over weighted but I doubt that it is that large an amount and would suggest to try removing only a little at a time.