An age-old question: ways to 60m.

[Centrals]

For reference:
The RB80 Semi-closed Rebreather: A Successful Exploration Tool

https://www.mares.com/en_US/horizon

The item is no longer manufactured.
And so are these: Biomarine Mk 15.5, Cis-Lunar Mk5 and Oroboros. There are plenty more discontinued CCR.

 

[rx7diver]

... A routine that works for me is to start the dive in the water with no mask breathing slowly and deeply till it’s about 6 BPM. I clear my mask and drop quickly, 2 to 3 minutes to 60m, I squint my eyes to kick in my night vision and get used to the loss of light. As the wreck appears I slow my descent and take a moment to relax and check time, depth and gas. ...

For deep Great Lakes wreck diving, we would descend on the mooring line to 10 ffw or so, just below the surface waves, and hang there for 3 minutes or so, slowing our breathing and pulse rates. And then drop slowly, without kicking, to depth, no faster than 60 fpm. (So, ~3.5 min to get to 200 ffw.) And then, once at depth, pause a moment to affix strobes, relax, and orient ourselves before continuing the working part of the dive.

The most narc I've ever felt is when I deliberately descended very quickly to depth, kicking a tiny bit to assist. Extreme, dark narc! I vowed to never, ever again do that! SS Kamloops off Isle Royale MI (Lake Superior).

rx7diver

 

[SelfDiver]

Okay I might throw another stone in this pond and summon next 30 pages of fighting but is not now a good time for revival something like of Draeger Dolphin which are still available as second hand and provide some sort of compromise between helium cost for OC and complexity of CCR? I approximately know what kind of portal to hell I am opening now, adding to war between air OC and CCR and Trimix OC adepts some sCCR guys (probably some of them still exist in this universe) but .....

In this context, there is no significant difference between SCR and CCR in terms of training, proficiency and currency.
The difference in unit cost is significant so it reduces the break-even point. However, SCR comes with other issues.
I really hope this summons 30 pages of fighting...I will make a new batch of popcorn. I was coaching in the pool all weekend and this topic came up.

 

[Celt]

For deep Great Lakes wreck diving, we would descend on the mooring line to 10 ffw or so, just below the surface waves, and hang there for 3 minutes or so, slowing our breathing and pulse rates. And then drop slowly, without kicking, to depth, no faster than 60 fpm. (So, ~3.5 min to get to 200 ffw.) And then, once at depth, pause a moment to affix strobes, relax, and orient ourselves before continuing the working part of the dive.

The most narc I've ever felt is when I deliberately descended very quickly to depth, kicking a tiny bit to assist. Extreme, dark narc! I vowed to never, ever again do that! SS Kamloops off Isle Royale MI (Lake Superior).

rx7diver

Dive buddies have said they experience the same thing, Ive had something similar on the SS Zeta. When I dropped onto the upturned hull it felt soft like cotton wool but it passed after a few minutes, I just busied myself with gear checks. A fast drop can be very disorienting in cold and poor visibility. People have different experiences with narcosis.

 

[Boarderguy]

For deep Great Lakes wreck diving, we would descend on the mooring line to 10 ffw or so, just below the surface waves, and hang there for 3 minutes or so, slowing our breathing and pulse rates. And then drop slowly, without kicking, to depth, no faster than 60 fpm. (So, ~3.5 min to get to 200 ffw.) And then, once at depth, pause a moment to affix strobes, relax, and orient ourselves before continuing the working part of the dive.

The most narc I've ever felt is when I deliberately descended very quickly to depth, kicking a tiny bit to assist. Extreme, dark narc! I vowed to never, ever again do that! SS Kamloops off Isle Royale MI (Lake Superior).

rx7diver

Dive buddies have said they experience the same thing, Ive had something similar on the SS Zeta. When I dropped onto the upturned hull it felt soft like cotton wool but it passed after a few minutes, I just busied myself with gear checks. A fast drop can be very disorienting in cold and poor visibility. People have different experiences with narcosis.

This is why when I do one of my favorite drops into 170fsw it takes nearly 5 min. Breathing good at the buoy before going under. Nice and easy down the line into the abyss. Trigger the scoot to adjust for current if needed or just a few kicks. Hit the brakes at 100, 130, 150, and 165. OK with buddy to move down or when solo verify time, depth, and air.

 

[rx7diver]

Dive buddies have said they experience the same thing, Ive had something similar on the SS Zeta. When I dropped onto the upturned hull it felt soft like cotton wool but it passed after a few minutes, I just busied myself with gear checks. A fast drop can be very disorienting in cold and poor visibility. People have different experiences with narcosis.

@Celt,

Do you have any good links to SS Zeta content? My google fu seems to be failing me. All I found so far is this: WRECK WRAK EPAVE WRACK PECIO Search a wreck.

TIA,
rx7diver

 

[Celt]

@Celt,

Do you have any good links to SS Zeta content? My google fu seems to be failing me. All I found so far is this: WRECK WRAK EPAVE WRACK PECIO Search a wreck.

TIA,
rx7diver

Check out a friend’s content Timmy Carey, on YouTube he could have a video of the Zeta.

 

[PfcAJ]

All these tricks to not feel narcosis are the same as the boil a frog analogy.

Not feeling it doesn’t mean it isn’t there.

Y’all goofy.

 

[SelfDiver]

So yall saying we should do OC Air to 70 meters? Then CCR for deeper?
Just need some clarity in my tiny ooga booga brain.