Need infos for a new DSS setup

[Safety Stop]

I'm sure Tobin have all the answers I need

Let's start...

My self : 6.1, 215 #

Tank : Single steel 100 HP

Drysuit : Bare CD4 (4 mm compressed neo) with rockboot, dry gloves

Underware : Bare T100 POLARWEAR

My BC : Zeagle TEC

Weight needed with my BC in fresh water : 38 #

Weight needed with my BC in sea water : 44 #

So Tobin, what do you recommand me for a HOG DSS setup for a Double 119 HP (Worthington), Dive Rite Band and Genesis manifold?

Thanks

 

[SparticleBrane]

Holy God, almost 40lbs of weight, PLUS double 119s?! You sound insanely overweighted.

 

[Safety Stop]

Holy God, almost 40lbs of weight, PLUS double 119s?! You sound insanely overweighted.

Sorry, I forgot to mention the weight I have right now is for a steel single 100 HP. I'm asking the right SS equipment for a double 119 HP config.

 

[SparticleBrane]

I'm still amazed that one would need 38 or 44 lbs of weight with a steel 100.

 

[cool_hardware52]

I'm sure Tobin have all the answers I need

Let's start...

My self : 6.1, 215 #

Tank : Single steel 100 HP

Drysuit : Bare CD4 (4 mm compressed neo) with rockboot, dry gloves

Underware : Bare T100 POLARWEAR

My BC : Zeagle TEC

Weight needed with my BC in fresh water : 38 #

Weight needed with my BC in sea water : 44 #

So Tobin, what do you recommand me for a HOG DSS setup for a Double 119 HP (Worthington), Dive Rite Band and Genesis manifold?

Thanks

I need two inputs to start the process, the first is the initial buoyancy of your exposure suit, the second is the tanks you will be using.

The tanks you plan to double are the 119's, got that. I am a bit surprised at the weight required, i.e. 44 lbs of lead with a HP 100.

A HP 100 is about -2 when empty or close to it. Your reg is about -2. That means you'd have 44 + 2 + 2 = 48 lbs of total ballast. Maybe 4 lbs is require to offset your current bc. That still leaves 44 lbs of ballast to sink you and your exposure suit. That's a LOT of lead.

I'd suggest getting in the pool with just your undies and 4mm suit and a bag of lead. Find out exactly how much lead is required to get you and the suit neutral when you have minimum gas in the suit.

Stand in neck deep water and vent the suit as much as you can. Add lead until your head goes under when you pick up your feet.

Tobin

 

[Safety Stop]

Did I mentionned it a DRY SUIT 4mm compressed ;-)

The test I did so far was :

Without undies : - 8
Minimum to be neutral with all my gear into soft water : 36 and sea water : 42 ( I added +2 for comfort under water... more air... less cold)

I'll do the test as you recommand and let you know the result.

Dont forget, I'm in cold Canada so the suit and undies must be thick ;-)

 

[cool_hardware52]

Did I mentionned it a DRY SUIT 4mm compred ;-)

Yes I understand it's a dry suit.

If it was just a 4mm wetsuit, i.e. uncompressed neoprene, I would expect it to be about 10-14 lb positive at most. Most 3 mm wetsuits are 4-8 lbs and most 5mm wetsuits are 14-18 lbs.

Most folks diving in a shell Drysuit with fairly thick undies end up in the low to mid 20's, 22-24 lbs positive. All in salt water.

If your neo drysuit is +12 and your undies are worth another 24, thats still only 36 lbs in salt, not 44.

I might be missing something, but your ballast numbers seem unusually high.

Knowing how buoyant your suit is has value, if you change other pieces of gear it's just a math problem.

Tobin

 

[Safety Stop]

I might be missing something, but your ballast numbers seem usually high.

Knowing how buoyant your suit is has value, if you change other pieces of gear it's just a math problem.

Tobin

Like I said, I'll do the test very soon :scubadive

Thanks for your help Tobin

 

[Safety Stop]

I need two inputs to start the process, the first is the initial buoyancy of your exposure suit, the second is the tanks you will be using.

I'd suggest getting in the pool with just your undies and 4mm suit and a bag of lead. Find out exactly how much lead is required to get you and the suit neutral when you have minimum gas in the suit.

Stand in neck deep water and vent the suit as much as you can. Add lead until your head goes under when you pick up your feet.

Tobin

I went to a pool with my 4 mm compressed and my undies with a bag of lead and I end up with 26 lbs. And to answer you second question, I'll have a double 2 X 119 HP. So, what's your recommandation???

 

[cool_hardware52]

I went to a pool with my 4 mm compressed and my undies with a bag of lead and I end up with 26 lbs. And to answer you second question, I'll have a double 2 X 119 HP. So, what's your recommandation???

SS, you will have about 19 lbs of back gas in your doubled 119's (air or nitrox)

You need to start your dive negative by the weight of your back gas + ~2 lbs.

19 + 2 = 21 lbs. That means you will have used 21 lbs of your wings capacity just to stay at the surface at the beginning of the dive.

You need another ~26 lbs of wing capacity to deal with a total drysuit failure, i.e. open zipper, blown out neck seal etc. 21 + 26 = 47 lbs.

You should also note that you will need 47 lbs of total ballast, 26 to sink your suit neutral, and 21 more to be negative by 21 at the start of the dive.

Your rig will be, with empty tanks, about -23 lbs. (Plate and harness, -7, bands and manifold -5, regs -5, empty worthington 119 2 x -2 = -4 canlight -~2) That leaves you about 24 lbs short. 24 lbs in a weight belt is a lot. Let's assume you put 8 lbs in soft weight pouches between your wing and back plate. Now your rig is -31 with empty tanks, and -50 with full bottles. You will need about 16 lbs in a belt.

You need a wing larger than 50 lbs to reliably float your rig. In our system that would be a Torus 57. 57 is enough to deal with the unlikely event of a total drysuit failure.

The Torus 57 is also a bit wider at the hips, which is very likely a help with a 16-18 lbs weight belt.

Let me know if you have other questions.

Tobin