Weighting help!!!

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enchantmentdivi
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Weighting help!!!

Post by enchantmentdivi »

I moved to Florida, and I’m heading to one of the springs to dive soon. Help me with my weighting!! In my dry suit (DUI FLX50/50), I used 28lbs in salt water. Now, I’ll be using a 3mm wetsuit in fresh water. Same MP Faber steel tank in both scenarios. If it helps, using a 3mm in salt water with an AL80, I need about 14lbs. My best guess is somewhere between 4-6lbs for 3mm with my 72. Or am I way off?? Help! TIA!
Jenn
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60south
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Re: Weighting help!!!

Post by 60south »

Yay! Warm, freshwater diving.

The only way to know for sure is to do a buoyancy check with a mostly-empty tank. But perhaps we can put you 'in the ballpark', yes?

First off, I doubt there is any conversion that will help when going from a drysuit to a 3mm wetsuit, there's just too many factors. So let's figure out the weighting based on your previous experience with a 3mm wetsuit...

Your Faber steel 72 is about 4 pounds negative when empty. The typical Luxfer AL 80 is positive about 4 lbs when empty. So by switching to a steel 72, you'll be 8 pounds heavier at the end of a dive. Start by taking 8 pounds off your previous weight of 14 lbs.

14 - 8 = 6 lbs, when using a steel 72.

Now, how much more can we take off because you'll be less buoyant in fresh water? Hard to say, since it depends on your physiology. Were it me, I'd stick with 6 pounds and just assume I'd be a bit over-weighted. If I were doing several dives I'd do more buoyancy checks and might end up taking off another couple of pounds, but I'd rather be a bit over-weighted than under-weighted to start.

Your original guess of 4-6 pounds is probably very good!

(Somebody please check my math!)
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H20doctor
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Re: Weighting help!!!

Post by H20doctor »

I'm going from saltwater to freshwater I usually drop about 10 lb..
I'm 5'10 165 I normally wear 20Lbs on my belt and 12 lbs on the back of my tank.. best way to check is find a lake
gear up and walk in... Get out of the water take off weight get back in... Fully loaded you want to do a complete exhale and be able to put your head underwater slowly sink..
This is with a full tank, as if you're ready to go for a dive.. it's funny because I remember doing this being a new diver and being in the water that cold day at Mukilteo with eight other students the objective goal was to exhale, and sink.. and if you didn't drop more weight..
For me and all these years I would rather be a little heavy, underwater because when you are too light and your tank has 1500 PSI, it's time to grab rocks or something because you're too light now and there's a safety stop
Last edited by H20doctor on Thu Jan 26, 2023 10:09 pm, edited 1 time in total.
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enchantmentdivi
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Re: Weighting help!!!

Post by enchantmentdivi »

60south wrote: Tue Jan 17, 2023 9:48 pm Yay! Warm, freshwater diving.

The only way to know for sure is to do a buoyancy check with a mostly-empty tank. But perhaps we can put you 'in the ballpark', yes?

First off, I doubt there is any conversion that will help when going from a drysuit to a 3mm wetsuit, there's just too many factors. So let's figure out the weighting based on your previous experience with a 3mm wetsuit...

Your Faber steel 72 is about 4 pounds negative when empty. The typical Luxfer AL 80 is positive about 4 lbs when empty. So by switching to a steel 72, you'll be 8 pounds heavier at the end of a dive. Start by taking 8 pounds off your previous weight of 14 lbs.

14 - 8 = 6 lbs, when using a steel 72.

Now, how much more can we take off because you'll be less buoyant in fresh water? Hard to say, since it depends on your physiology. Were it me, I'd stick with 6 pounds and just assume I'd be a bit over-weighted. If I were doing several dives I'd do more buoyancy checks and might end up taking off another couple of pounds, but I'd rather be a bit over-weighted than under-weighted to start.

Your original guess of 4-6 pounds is probably very good!

(Somebody please check my math!)
Thanks for processing through this with me! The magic number ended up being TWO pounds! It was freaking awesome. 150+’ visibility was amazing too. :)
Jenn
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enchantmentdivi
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Re: Weighting help!!!

Post by enchantmentdivi »

H20doctor wrote: Thu Jan 19, 2023 8:59 pm I'm going from saltwater to freshwater I usually drop about 10 lb..
I'm 5'10 165 I normally wear 20Lbs on my belt and 12 lbs on the back of my tank.. best way to check is find a lake
gear up and walk in... Get out of the water take off weight get back in... Fully loaded you want to do a complete exhale and be able to put your head underwater slowly sink..
This is where the full tank as if you're ready to go for a dive
Thanks! 2 lbs was perfect, but it felt so weird needing so dang little.
Jenn
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60south
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Re: Weighting help!!!

Post by 60south »

enchantmentdivi wrote: Sun Jan 22, 2023 5:35 pmThe magic number ended up being TWO pounds! It was freaking awesome. 150+’ visibility was amazing too. :)
Yay! Log it! Next time you'll be dialed-in.
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H20doctor
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Re: Weighting help!!!

Post by H20doctor »

I'm glad Northwest Dive club is still here to help and a resource for diving in the Pacific Northwest
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