The Jet Fin Buoyancy Conundrum With Neoprene Suits

[Underwatermonk]

Hi everyone I‘ve been reading this forum for a long time and I‘ve just recently decided to start my first thread.

I just bought a pair of Jet Fins since I read everywhere that they where the best for cave7tech diving diving, which is mostly what I do since I live in cave diving paradise. Also I love this fins because they where my first pair of fins when I started diving 25 years ago but somewhere along the way they got lost.

I dove with this fins in the ocean and they where great but yesterday I did my first cave (an "easy" one) with them and I suffered all the way because of the negative buoyancy this fins have. It was imposible to keep a good trim. I only use neoprene suits for cave diving, mostly 3mm since I get to hot with the 5mm (which I have‘t tried with this fins yet).

I‘m thinking of getting into side mount but now I‘m worried that this fins might be too heavy. I found on this forum that putting some sort of weight on the neck of the tank or tanks (not adding weight but redistributing it) can help with getting a more neutral trim. I haven‘t tried this but it makes sense.

My concern is that without a dry suit this fins might just not work which makes me very sad since I love the propulsion and the control I get from them particularly for underwater video. I love everything about this fins except for the buoyancy so I would like to find a solution.

Before I bail on this fins I wanted to ask if anybody has experience with this fins using neoprene suits with regular or side-mount setups.

Sorry for my weird english but any help would be most appreciated.

 

[L13]

Hi everyone I‘ve been reading this forum for a long time and I‘ve just recently decided to start my first thread.

I just bought a pair of Jet Fins since I read everywhere that they where the best for cave7tech diving diving, which is mostly what I do since I live in cave diving paradise. Also I love this fins because they where my first pair of fins when I started diving 25 years ago but somewhere along the way they got lost.

I dove with this fins in the ocean and they where great but yesterday I did my first cave (an "easy" one) with them and I suffered all the way because of the negative buoyancy this fins have. It was imposible to keep a good trim. I only use neoprene suits for cave diving, mostly 3mm since I get to hot with the 5mm (which I have‘t tried with this fins yet).

I‘m thinking of getting into side mount but now I‘m worried that this fins might be too heavy. I found on this forum that putting some sort of weight on the neck of the tank or tanks (not adding weight but redistributing it) can help with getting a more neutral trim. I haven‘t tried this but it makes sense.

My concern is that without a dry suit this fins might just not work which makes me very sad since I love the propulsion and the control I get from them particularly for underwater video. I love everything about this fins except for the buoyancy so I would like to find a solution.

Before I bail on this fins I wanted to ask if anybody has experience with this fins using neoprene suits with regular or side-mount setups.

Sorry for my weird english but any help would be most appreciated.

I've use SP jet fins with a 3mm in side mount. I need very little weight. depending on the details, (fresh/salt, steel/AL) I put the weight either between my shoulder blades, or on my shoulder straps as high as possible to keep them out of the way. Works just fine.

At some point I'm going to get some neutral/positive tech fins and save the SP jet fins for when I dive dry (which is actually what I do most of the time right now).

 

[Norwegian Cave Diver]

Go see the people at Protec, they can certainly help you sort out the trim issues. All of them are great people.

 

[poolisopen]

I only use jet fin when in drysuit. There are good fins that are more neutrally buoyant like RK3 or Hollis F1 LT for wetsuit diving.

 

[MaxBottomtime]

I've been wearing Jet fins for a few decades with drysuits, 7mm and 3mm wetsuits, dive skin, and board shorts. I haven't noticed any buoyancy issues.

 

[lexvil]

This is likely more of a trim issue.

 

[Pressurehead]

I just bought a pair of Jet Fins since I read everywhere that they where the best for cave7tech diving diving, which is mostly what I do since I live in cave diving paradise.

What fins were you using before the jet fins for your cave diving?

 

[oya]

The butts of your sidemount tanks will get lighter as you breath them down.

The Jets will offset that.

Yea, you’ll be footheavy at the beginning of the dive. But at the end of the dove you’ll be happy they’re there.

 

[rongoodman]

Consider the Deep Six Eddy fins or OMS Slipstreams. You’ll have the propulsion and control, more comfortable foot pockets, and less weight.

 

[Underwater Tourist]

I second OMS Slipstreams

I was diving a brand new 5mm (although boots were very old) with those fins and felt wonderful from the very beginning to the very end of the dive (SM AL tanks)

Apeks RK3 are also popular now, but I havent tried them