Wing Lift - Cold water, 8/7 semi-dry suit

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mtoyama

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TL;DR:
  • Cold water diver, mostly (Monterey, CA). I wear a 8/7mm semi-dry wetsuit (size Medium Large Tall, I am 6'2 185).
  • I typically dive a single Steel HP 100
  • Plan on using weight belt
  • Still learning what kind of diving I like, but not really diving past 60' right now. Plan on doing Advanced and Rescue this year.
  • Optimal Buoyancy Calculator data for me
  • Will 30 lbs DGX singles wing be enough?

Hello folks,

Posting after doing a lot of research on this. Buying my first BCD. After lots of reading and getting advice from experienced folks, I've decided to go BP/W. Seems economical and the modularity will allow the system to grow as I learn what I want as a diver. I just bought a DGX 30 lbs single tank wing, but I'm slightly worried it may not be enough lift for me. See stats above. The OptimalBuoyancy puts me at 30-36 lbs of lift. If I play with some of the variables it can go down to 26-36, or up to 30-40+, etc. Like if the wetsuit is "Standard" or "Soft" (not sure which is mine), or if I add a 3mm vest.

If I understand correctly (after reading A LOT), there are two goals in figuring lift:
  • Wing has enough lift to float your rig without you attached to it
  • Wing has enough lift to compensate for the loss of wetsuit buoyancy at depth
I plan on wearing a weight belt, so perhaps the first bullet is not a big deal. The second one I'm not sure about. It kind of feels like 30 lbs hits a minimum looking at the buoyancy calculator, giving me little room to mess with my kit (e.g. I'm thinking about adding a 3mm vest as I'm still cold in the water).

Also, I'm wondering if there are other situations where I'd want more lift, ie sometimes I do conservation dives where we're doing work rather than just touring, or in a rescue situation.

I jumped on this 30# wing as my other option, the VDH 35#, has been out of stock for some time with no ETA.

Anything else I'm missing here?

Thanks,
Mike T.
 

tbone1004

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I think 30lbs is going to be marginal for you. I'd look at the Dive Rite Voyager which has a bit of a taper at the bottom to give you some more lift at your hips to help with the weight belt.
 

runsongas

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use some cam band pockets or a weighted sta if a heavy weight belt causes trim issues. the dgx 30 is a bit marginal if you are diving to 100ft or deeper often at north monastery, pt lobos, or off one of the local boats at the pinnacles, but switching to a drysuit becomes a good idea at that point.
 

-JD-

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And I'll throw out there ... What is your backup buoyancy plan if there is a wing failure?

With a weight belt only, ballast ditching is all or nothing.
 

mtoyama

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And I'll throw out there ... What is your backup buoyancy plan if there is a wing failure?

With a weight belt only, ballast ditching is all or nothing.

Hmm, can you explain the weight belt only situation?

I didn't plan for all of it to be weight belt. Just noted I intended on using one. For example, I bought an S/S plate.
 

Brett Hatch

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Hi @mtoyama, I'm 5'11", 180. I dive in Monterey often, with similar gear: a size medium large long SolAfx 8/7mm semi-dry wetsuit, and usually HP100 tanks. With the steel backplate, I need around 14lbs of lead to dive wet. I use the 32lb OMS single wing, which is plenty of lift for me. I also dive a trilam drysuit here, and the same setup works fine, just need a little bit more lead. I have never been in a situation where I needed to completely fill my 32lb wing, so I doubt I would notice any difference between that and a 30lb wing. You should be fine.

I personally prefer to put most of the lead on my weight belt as well. I like to use a stretchy rubber weight belt like freedivers often use, instead of the non-stretchy plastic ones. MAKO Spearguns makes a good belt for cheap, and it pairs well with their "pinch" weights.

By the way, if you really want to be sure it will be enough, you might want to test your wetsuit to see just how buoyant it is. Stuff the suit into a mesh bag with, say, 10 lbs of lead. Keep adding little bits of lead until the suit begins to sink. Add up the weight of all the lead, and that's the amount of lift your wing needs to provide to compensate for suit compression. Add to that the amount of gas you're diving (100 cubic feet of air weighs 8 pounds), and you will find the absolute minimum amount of lift you need to bring along. Maybe throw in a couple extra pounds for a margin of error.

Edit to add: if you are still cold in an 8/7mm semi-dry, then you might want to start looking at drysuits. I did maybe 50 dives or so in Monterey in my SolAfx, and then the cold started to be the limiting factor. I'm really happy with my drysuit, it's from SeaSkin, cost me about $1400 including some expensive options (pockets, P-valve, dryglove system), and is made to measure so the fit is good. If I'm doing shallow dives on a warm day I still use the wetsuit sometimes, but go for the drysuit probably 8 days out of 10.
 

mtoyama

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Hi @mtoyama, I'm 5'11", 180. I dive in Monterey often, with similar gear: a size medium large long SolAfx 8/7mm semi-dry wetsuit, and usually HP100 tanks. With the steel backplate, I need around 14lbs of lead to dive wet. I use the 32lb OMS single wing, which is plenty of lift for me. I also dive a trilam drysuit here, and the same setup works fine, just need a little bit more lead. I have never been in a situation where I needed to completely fill my 32lb wing, so I doubt I would notice any difference between that and a 30lb wing. You should be fine.

I personally prefer to put most of the lead on my weight belt as well. I like to use a stretchy rubber weight belt like freedivers often use, instead of the non-stretchy plastic ones. MAKO Spearguns makes a good belt for cheap, and it pairs well with their "pinch" weights.

By the way, if you really want to be sure it will be enough, you might want to test your wetsuit to see just how buoyant it is. Stuff the suit into a mesh bag with, say, 10 lbs of lead. Keep adding little bits of lead until the suit begins to sink. Add up the weight of all the lead, and that's the amount of lift your wing needs to provide to compensate for suit compression. Add to that the amount of gas you're diving (100 cubic feet of air weighs 8 pounds), and you will find the absolute minimum amount of lift you need to bring along. Maybe throw in a couple extra pounds for a margin of error.

Edit to add: if you are still cold in an 8/7mm semi-dry, then you might want to start looking at drysuits. I did maybe 50 dives or so in Monterey in my SolAfx, and then the cold started to be the limiting factor. I'm really happy with my drysuit, it's from SeaSkin, cost me about $1400 including some expensive options (pockets, P-valve, dryglove system), and is made to measure so the fit is good. If I'm doing shallow dives on a warm day I still use the wetsuit sometimes, but go for the drysuit probably 8 days out of 10.

We're nearly the same! Yeah, I just got my 8/7 semi-dry (bare velocity evolution) and I'm still cold. I will do the weight test -- it is something I have been meaning to do. Throw my gloves and boots too yes?

I did pick up a rubber belt belt but haven't been able to find my weights yet! How do you like pinch weights vs regular ones?
 

Brett Hatch

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We're nearly the same! Yeah, I just got my 8/7 semi-dry (bare velocity evolution) and I'm still cold.
How is the fit of the suit? If it's loose near the seals, then it will allow water to flush in and out. If it's loose near your body, it will allow large amounts of water can accumulate there. Both of which will undermine your body's ability to retain heat inside the suit. When you wear it, the suit should have no wrinkles or baggy parts.

Also, my wetsuit only makes good ankle/wrist seals if I wear my booties and gloves on the outside of the suit. For awhile I was putting my gloves on the inside, and swapping it to the outside helped a lot. If you're doing this, you might try to reverse the ordering and see if it helps. But if the suit fits well and is worn correctly, honestly, I have doubts that a 3mm vest will help much. It's cheaper than a drysuit though, so might be worth trying.

I will do the weight test -- it is something I have been meaning to do. Throw my gloves and boots too yes?
Sure, might as well throw them in if you like, although I think you'll find that they contribute a very small amount of buoyancy. Maybe 1 lb between all of it.

I did pick up a rubber belt belt but haven't been able to find my weights yet! How do you like pinch weights vs regular ones?

I like the pinch weights a lot. As I add or remove weight, the belt never changes sizes, so I can always use the same hole. And the weights never feel like they're going to fall off the belt, yet are easy to slide around when you do want to move them. The stretchiness of the rubber belt keeps it in place as I descend (whereas a nylon belt will loosen as your wetsuit compresses with depth, and need to be adjusted on the bottom). The combination works well, I recommend it. The ones @runsongas linked look just like my MAKO ones, but run a bit cheaper. Nice find!
 

mtoyama

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How is the fit of the suit? If it's loose near the seals, then it will allow water to flush in and out. If it's loose near your body, it will allow large amounts of water can accumulate there. Both of which will undermine your body's ability to retain heat inside the suit. When you wear it, the suit should have no wrinkles or baggy parts.

Also, my wetsuit only makes good ankle/wrist seals if I wear my booties and gloves on the outside of the suit. For awhile I was putting my gloves on the inside, and swapping it to the outside helped a lot. If you're doing this, you might try to reverse the ordering and see if it helps. But if the suit fits well and is worn correctly, honestly, I have doubts that a 3mm vest will help much. It's cheaper than a drysuit though, so might be worth trying.

Dan at Diver Dan's was confused about my problem (I didn't buy it from them, but I did discuss it with him while helping my gf with wetsuits). The suit seems to fit well when dry. Seals are good and tight. Not much extra room. There's a little bit of bulging at the zipper when I move my arms, and a little room in the neck.

I did a surface swim out to Tanker's (urchin culling). Comfy during swim. Pretty sure there was 0 water in the core of my suit when I dropped down through the thermocline to 30', temp 53F. Then, it felt COLD. Like I was in a very cold room. Not like there was water exchange, just everything felt cold immediately.

Maybe I should have waited a little bit for the space in the suit to heat up but I ended up intentionally flooding the suit to get water next to my body to warm up. When I flooded it, it felt like there was no water inside as I could feel it running down my back.

I am diving on Friday so I am going to try a couple things. Just try diving it again without flooding, see if it warms up. I also have a 3mm vest I picked up, perhaps there's too much room in the core even though it seems to fit OK.

It will be sad if the suit doesn't work, because it was expensive as suits are. MLL in SolaFx seems to be a great size for me based on the numbers and we're approaching Diver Dan's sale window, so that's my fallback. Not ready for dry suit yet

pinch weights worth it if you were already planning to buy new lead. there is a local seller that has them at a reasonable price. Spearfishing Diving Lead Neptonics Weight - sporting goods - by...

i just use old lead i picked up for 1/lb or less.

Great tip, I will buy these as I can pick up locally. Shipping lead weight seems silly.
 
https://www.shearwater.com/products/perdix-ai/

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