Buoyant Fins??

[TimAZ]

I have a friend, (relatively new diver) complaining of his legs being significantly negative buoyant and the resulting back pain trying to hold them up. I've discussed with him how much weight he's using and how his BC is trimmed and I don't see any issues there. I'm skeptical, but he wants to try fins with significant positive buoyancy. I told him as far as I knew, just about everything out there was between very slightly buoyant to relatively negative, but I'd ask here. After all if any one would know, s/hes on the board. Thanks in advance.

 

[gregorio]

What about putting tank a bit higher?

 

[TheRedHead]

I think it is a trim and/or technique issue.

 

[SteveFass]

sounds like addressing the symptom and not the problem, but how about thick neoprene boots or socks?

 

[PerroneFord]

How much weight on the weight belt?

 

[divingjd]

Because you already said you had checked weighting and trim, the two most obvious sources of the problem, I will address the specific question you raised. I believe that you are correct that the great majority, if not all, of the fins that are positively buoyant are only slightly positive. I have Scubapro TwinJets in yellow and blue, both are slightly positive. If you put them underwater, they take a little time to surface - they don't pop up like a cork. As Steve Fass suggested, I think boots would have a lot more effect on buoyancy.

 

[Splitlip]

Scuba lab used to include bouyancy characteristics of fins when they tested. Maybe you can check their website for past tests.

 

[ChrisA]

Yes there are buoyant fins. They are great if you loose them in the surf because you have a chance of finding them. But they are not that buoyant. Maybe 1/4 pound or so. Why not take one of the weights off his belt or bc and tread it through a tank cam band. That might move five pounds up higher. Yes you said yu checked his trim. But hs trim is wrong. If you don't believe me have him find a big rock and hold it in front of his head while he swimms. I bet you a beer that his feet don't sink when he holds a 15 pound rock out past his head. He needs to move some lead forward. Not the tank, some lead.

 

[PerroneFord]

Yes you said yu checked his trim. But hs trim is wrong. If you don't believe me have him find a big rock and hold it in front of his head while he swimms. I bet you a beer that his feet don't sink when he holds a 15 pound rock out past his head. He needs to move some lead forward. Not the tank, some lead.

:lol:

Man, quit fooling around. Bet him a case. Hell bet $100. It's a sure bet. (Assuming he's not diving vertically)

 

[TimAZ]

How much weight on the weight belt?

He claims 6 pounds ditchable and four pounds non-ditchable using a 7 mil in fresh water.