Fusion Drysuit and BCD weight capacity?

[jdevic]

I only started diving last year and have about 40 dives so far. Two months ago, I invested in my first set of regulator and bcd (mares abyss navy + aqualung zuma bcd) for mostly warm water diving while traveling. A weeks ago, I placed order for a fusion one drysuit + thermal undergarments (on back order) in hope of diving more in Ontario Lakes and possibly British Columbia.

I noticed that my Zuma BC can carry maximum 30lbs of weight (2x10lb + additional 10b trim pocket) and has a rated lift capacity of 34lbs.

My questions are:
1) Can I just carry the weight using weight belt if it exceeds the weight pocket capacity?
2) Does it matter if the weight I carry exceeds the bcd lift capacity? I assume I can use the dry suit for additional buoyancy, right?
3) I am 210 lbs. How much weight approximately I will need with the Fusion One and Thermal in fresh and salt water? My reference points are:
skin / shorty - salt 14 lbs.
5.5mm full/new - salt, 24 lbs.
5mm full - fresh, 15 lbs
7mm full + 7mm core warmer with hood, fresh 22 lbs.

Thank you very much!

 

[tbone1004]

1. sort of
2. yes because if the drysuit fails you have to drop lead. Your drysuit is not for buoyancy, it is for thermal protection, contrary to anything that any agency or instructor tells you
3. literally no idea because drysuit buoyancy is largely dependent on the individual diving it. Fresh and salt water doesn't matter as it is a function of displacement. BCD's actually change their lift capacity in fresh and salt water, so they pick up a few pounds of lift due to the density change in salt water.

the biggest issue with #1 is that you will have to have your bc very tight to prevent it from riding up since it won't accept a crotch strap. huge reason why in drysuits especially I don't think standard bcd's are a good idea.

 

[runsongas]

start at what you would use with the farmer john in salt water and dial it in from there.

 

[Patoux01]

I noticed that my Zuma BC can carry maximum 30lbs of weight (2x10lb + additional 10b trim pocket) and has a rated lift capacity of 34lbs.

My questions are:
1) Can I just carry the weight using weight belt if it exceeds the weight pocket capacity?
2) Does it matter if the weight I carry exceeds the bcd lift capacity? I assume I can use the dry suit for additional buoyancy, right?
3) I am 210 lbs. How much weight approximately I will need with the Fusion One and Thermal in fresh and salt water?

1) Yes, and I personally advocate for having "both parts" of a diver to be roughly neutral, ie the diver should carry some weight and some in the BC.
2) Yes and no. Yes it matters if you're heavily overweighted, no it doesn't if you're properly weighted. No the drysuit should not be used for buoyancy. What I mean with "it doesn't matter" is that if you (your body) requires 50 pounds of weight to get neutral (that's an imaginary figure), you do not need a BCD with > 50#. A BCD is there to compensate for the change of buoyancy in the suit and the weight of gas you carry. It should also be able to float "by itself" (without you in it) on the surface with the tank and weights in it. Therefore you should not be putting 30# of weight in a BC that has 34# of lift, because it's gonna sink with some tanks, so if you throw it out of the boat to gear up in the water, you'd see it go down without you .
3) Impossible to say. A starting point would be around 20#, but you need to do a weight check.

 

[jdevic]

Thank you very much for the replies. So, it seems I do not necessarily need a new standard bcd?

 

[g1138]

I noticed that my Zuma BC can carry maximum 30lbs of weight (2x10lb + additional 10b trim pocket) and has a rated lift capacity of 34lbs.

Answers below in blue, but essentially try it out before looking for a new BC. I think you'll be able to fit under the lift capacity.

My questions are:
1) Can I just carry the weight using weight belt if it exceeds the weight pocket capacity?
Yes if you're still under the total BC lift capacity.

2) Does it matter if the weight I carry exceeds the bcd lift capacity? I assume I can use the dry suit for additional buoyancy, right?
Yes; Yes/No (technically No according to protocol).

With a drysuit, your buoyancy for exposure protection changes with how much air you put into it on the surface.
So it's highly variable and for emergencies, a suit flood could render this essentially neutral depending on undergarments.
There is a risk with exceeding BC lift capacity and relying on the drysuit to compensate. Regardless of where you put the weight.
On the surface the BC is primarily for staying positive. Drysuit is inflated for comfort.
Over-inflate the drysuit for buoyancy and you'll can have trouble swimming. This is exacerbated by drysuits maybe approaching a size too big.

Underwater you first prioritize Drysuit for buoyancy until you have enough fluff. Once you have enough fluff, additional buoyancy is then relied upon via the BC. You'll kinda notice this is the same concept as your surface procedure.

For recreational diving, single tank, proper weighting, above 40ft: you'll probably only use your drysuit to get neutral. In my experience it'll be rare to put enough air for comfort and still be negative; unless you're overweighted.

3) I am 210 lbs. How much weight approximately I will need with the Fusion One and Thermal in fresh and salt water? My reference points are:
skin / shorty - salt 14 lbs.
5.5mm full/new - salt, 24 lbs.
5mm full - fresh, 15 lbs
7mm full + 7mm core warmer with hood, fresh 22 lbs.

Depends. My intuition would be to start you with 22lbs and do a buoyancy check.
Basically a person's 7mm 2piece weighting.
Starting out you'll probably over-inflate your drysuit and carry more weight until you get more dives in with it.
It is ok to feel snug UW in a drysuit, as long as you don't come home with any hickeys. ;P

 

[jdevic]

Answers below in blue, but essentially try it out before looking for a new BC. I think you'll be able to fit under the lift capacity.

My questions are:
1) Can I just carry the weight using weight belt if it exceeds the weight pocket capacity?
Yes if you're still under the total BC lift capacity.

2) Does it matter if the weight I carry exceeds the bcd lift capacity? I assume I can use the dry suit for additional buoyancy, right?
Yes; Yes/No (technically No according to protocol).

...

Thank you! Very helpful!
I noticed that you are from CHS. Thinking about a long weekend in CHS in November...would you recommend I bringing the scuba gear along?

 

[tbone1004]

Thank you! Very helpful!
I noticed that you are from CHS. Thinking about a long weekend in CHS in November...would you recommend I bringing the scuba gear along?

not unless you plan on driving north to the nice diving....

 

[g1138]

Thank you! Very helpful!
I noticed that you are from CHS. Thinking about a long weekend in CHS in November...would you recommend I bringing the scuba gear along?

Nope, not a good dive destination. Plus no one dives after September, "too cold". Summertime it's either fossil diving the river or boat diving ocean at one of a short number of sites. Mostly weather cancels trips.
Most of us go to Florida or North Carolina.
Entirety of my recreational experience was when I was in Monterey, CA. I dive here for work now.