How Negatively Buoyant Are ScubaPro Jet Fins?

[Scuba_Noob]

How negatively buoyant are ScubaPro Jet Fins? Specific numbers please.

I just ordered one and want to calculate how much weight I can remove from my ankles.

Yes, I have read the countless Jet Fin threads, but nobody knows the exact number. Please only answer if you know at least a general number.

(PS I know I've posted a lot in this section recently)

EDIT: Large size, without spring straps (give me the numbers for with spring straps too).

 

[Blue Sparkle]

I don't have a number (so I probably should not be posting), but from what I have seen the size M and size L are a fair bit smaller (blade) than the XL and XXL, so it might help to post which size you ordered.

For example, I imagine that a pair of XXL's might be quite a bit more negative than my M's (?)

 

[Scuba_Noob]

Oh, yeah, I ordered a Large size (thanks for the suggestion).

 

[Tortuga68]

With or without springstraps? What were your old fins? How much weight do you have on your ankles? Diving dry or wet?

 

[ajduplessis]

Compared to what?

IMO they are not that negative. I have a large pair with spring straps and dive dry& wet with them. They are very heavy compared to my Seawing Novas, but you don’t feel them in the water. If you don't have strong leg muscle they might feel heavy, but that because of the way the work (thrust & resistance). You body position in the water will also have an effect on how they feel.

 

[Scuba_Noob]

Sigh, this is why I asked for specific numbers. I don't care about the comparisons to other fins. I want to know, is it 2lbs negatively buoyant? Is it 1lb negatively buoyant? Without specific numbers, there really is no point to this thread; it's just like the dozen other threads talking about how the Jet Fins are negatively buoyant.

 

[Lobzilla]

One Scubapro Jet fin in XL (newer model without arrow in the SP logo) with large Halcyon spring strap weighs 3.3lbs dry and has a fresh water buoyancy of -0.6lbs.
My guess is that the size L is about 80-85% of that.

This is probably less than what you hoped for. Nevertheless, try to remove the ankle weights and fix the trim with posture and correct positioning of tank and ballast weights.

 

[Blue Sparkle]

One Scubapro Jet fin in XL (newer model without arrow in the SP logo)...

Slight tangent, but that is interesting. By "arrow" do you mean the "lightning bolt" that pierces the logo (sounds like it). I have an old pair of Jet fins, and from research it was determined that they began putting the lightning bolt on in (I forget exactly now, but) around 1985. Mine are pre-then because they don't have the lightning bolt. I have "heard" that the rubber compound was changed slightly when they added the lightning bolt back then.

Sounds like maybe they have changed again and removed the lightning bolt? Interesting.

 

[Lobzilla]

Slight tangent, but that is interesting. By "arrow" do you mean the "lightning bolt" that pierces the logo (sounds like it). I have an old pair of Jet fins, and from research it was determined that they began putting the lightning bolt on in (I forget exactly now, but) around 1985. Mine are pre-then because they don't have the lightning bolt. I have "heard" that the rubber compound was changed slightly when they added the lightning bolt back then.

Sounds like maybe they have changed again and removed the lightning bolt? Interesting.

I may be wrong about my fins (without lightning bolt) being of newer vintage since I bought them used.

 

[ppo2_diver]

They probably around -1 lb. They are not much.