No BCD diving...

[Nemrod]

It is rare that I put more than a puff of air in my wing. It does come in handy when I have my camera so I don't have to leave a weight on the bottom.

I like my Oxy 18 but I would not mind an Oxy 9. A micro wing. Make it so it rolls up like a sausage for transport.

Minimalism is the new wave, greener, meaner, leaner.

N

 

[Eric Sedletzky]

I'll bet I am at the upper spectrum of buoyancy swing issues around here with no BC diving.
I dive in cold water mid 40's to low 50's.
I use a 7mm custom wetsuit.

Yes there are many more variables when you have to wear thicker suits. But it's not impossible to overcome and to manage.

Here are some of the things I found:
Off the rack suits from dive shops in the 7 -8mm range are too spongy to work well without buoyancy compensation. I've felt some suits in shops that seemed way spongy. Those suits compress in the first 30 feet something horrible so IMO aren't suitable for minimalism, at least not around here.
I found out that there is a whole range of materials available outside of what they use for off-the-rack LDS suits.
I had a custom suit made out of some super dense material, beaver tail cut, attached hood.
The swing is minimal and so buoyancy is manageable in the 33 foot "critical" zone.

I have to weight myself lighter (relative to the thickness of the suit) to make up for the heaviness at depth.
So when descending I fight my way down for the first 15 to 20 feet or so before I begin to break neutral. I probably have a shallower manageable bottom depth than someone using a thinner suit, but I can do dives down to about 60-70 feet before the heaviness becomes unmanagable. Most of my backpack dives are in the 30 to 50 foot range.

The safety feature of course is to dump the weightbelt and make your way to the top. I purposely keep my NDL's low so I can make a direct ascent if needed. Using an appropriate nitrox mixture is a bonus. With no BC diving there isn't really much danger of a rocket ascent because there is no air cell to expand (if you dump your belt in an emergency). Wetsuits don't expand enough to form an out of control missile ascent.

Another thing I found was that the longer I am in the water and depending on depth and suit crush, as the air is used up in my tank, the suit has cooled off and the air cells have been compressed, both of which reduce the buoyancy of the suit, which counters the lightening of the tank.
So, actually I don't get a huge weight swing from the start of the dive to the end of the dive. With this in mind I have removed quite a bit of weight off my belt that I would normally have had on to deal with the end of the dive and a light tank.

Lounging around on the surface and having enough buoyancy to surface swim and such is a breeze in a thicker suit. I can go out without any float.
With thinner suits the buoyancy suspension vs. the weight of the tank/plate at the surface is not as great so therefore a float of some sort to rest on is beneficial.

 

[Eric Sedletzky]

See: monkey-diving.com - Home

Monkey diving is diving without a BC, sidemount and with a scooter. Most of this seems to occur in warm water, but there is some in dry suit based monkey diving in the Pacific Northwest.

There's a guy in CA doing this, He dives in lake Tahoe all the time.
Diving without a BC completely removes the option to elevator dive.


Edit: I just remebered who it is, FDog.

 

[syntaxerrorsix]

I have no experience here whatsoever; are steel tanks ever used?

 

[Wookie]

I have no experience here whatsoever; are steel tanks ever used?

You need to know that back in the day, all that was available (pretty much) was steel 72's. I still have a few old-timer crew members that dive without a BC or horsecollar. I certainly don't make them. I require some means to check the pressure in your tank besides a j-valve, and a depth and timing device. We dive in warm enough water that a rash guard is plenty of exposure protection.

With that said, if you jump in the water without a bouyancy device and we have to rescue you because you don't really know how to dive without one, we'll probably have you put one on.

 

[syntaxerrorsix]

You need to know that back in the day, all that was available (pretty much) was steel 72's. I still have a few old-timer crew members that dive without a BC or horsecollar. I certainly don't make them. I require some means to check the pressure in your tank besides a j-valve, and a depth and timing device. We dive in warm enough water that a rash guard is plenty of exposure protection.

With that said, if you jump in the water without a bouyancy device and we have to rescue you because you don't really know how to dive without one, we'll probably have you put one on.

It will be safe to assume that me and my double 95's aren't really headed in that sort of direction but thanks for the info

 

[LeadTurn_SD]

I have no experience here whatsoever; are steel tanks ever used?

My intial years diving sans-BC was with a steel 72. I still have that tank (original hydro 1976, bought it new that year ). I wore a two-piece beaver tail USD wetsuit; I'm remembering it was equivalent to a current 5mm in thickness. Because it was a beaver tail design, there was only slight overlap between top and bottom of the suit, so it was not excessively buoyant. I wore a weightbelt and either an aluminum Hawaiian back pack, or plastic cam-pack.

With a steel tank you will be more negative than an aluminum tank and will need to consider your weighting carefully.

As others have mentioned, you'll generally dive significantly "lighter" than you'd normally weight yourself with a BC. I used to weight myself for "neutral" at the surface with a full tank, so that it was only necessary to gently tread water to stay afloat at the start of the dive, and I was a bit positive on the surface at the end. But this was with thinner wetsuits that did not have excessive buoyancy to lose.

For colder water and thicker wetsuits, refer to what ZKY posted regarding correct weighting.

Best wishes.

 

[Thalassamania]

FWIW, a number of cave divers enjoy the no-bcd lifestyle. Steve Bogaerts ether dives without a BCD or uses a modified water bladder as a minimalist BCD in the small of his back. This seems to give some of the benefits of buoyancy compensation while offering the streamlining and freedom of movement of diving without a BCD.

gosidemount.com

I was thinking about modifying a camel pac for diving, I'm glad to see someone's already ahead of me in that concept that I can learn from.

 

[syntaxerrorsix]

I was thinking about modifying a camel pac for diving, I'm glad to see someone's already ahead of me in that concept that I can learn from.

Check out thermoplastic welding techniques. We use a PVC in the single ply industry anywhere from 48 mil to 120 mil which uses plasticizers that render it extremely flexible and can be welded together in any size or shape you like. Not nearly as refined as RF welding thin plastics and nylons but If I chose to I could create a monolithic bladder in short order and you could as well with a little instruction.

 

[FredT]

T-shirt and shorts with a 72 no air bag is usually needed. Even if dragging one it shouldn't hold any air until you surface after the dive. This is a if you don't need it, you may not want to take it thing.

OTOH on the (hopefully) very rare occasions where you find yourself with an unexpected looooonnnnggg surface swim to the beach a back inflate you can rest on while swimming in is a very nice thing to have. I've done 2 of those where the time to swim in was over 6 hours. This is the "plan B" option of getting out of the water without involving the boat you went out on, or the worst possible current on a beach dive. Personally if I don't like the Plan B prospects I'll stay on the boat/beach.