Single Tank Sidemount

[MScorpa]

I haven't been in my singles SM rig in a few months and this thread had me jonesing to get it back out. What a joy! I thought why can't all my diving be this easy! I would be a happy to dive like this forever. Well, maybe not forever, since I get bored easily, but it is pretty perfect. And I could add the 2nd cylinder in a jiff , it would be just as easy, to satisfy the redundancy naysayers. It's a tool. Not for deep or deco stuff. But warm blue water, it's the right tool for me.

What kind of rig are you diving? I would piece together a more minimalistic rig with a trim pillow for easier travel like Andy but I'm taking the xDeep Stealth 2.0 since I will be in cold water. I'm going to need a bit of weight and the Stealth accomodates that nicely.

 

[a878bob]

I have two. My lightweight rig is a modified utd z-trim. My own plates, low profile d rings, and xs scuba weight pouches attached, etc. The bladder is tiny, it weighs nothing, and travels small.

Cold water deco is heavily modified Manta. I couldn't travel with it. Sidemount Deco Rig - YouTube

Two different tools for two diffent jobs.

 

[SangP]

Hi Guys,

I've been outta the game for ages and only recently do I have some spare time, albeit short time lol.

Anyway, I do mostly open water boat dives around South East Asia in mild to swift currents.

I'm using skeleton harness of my own design (similar to the razor harness), an Oxycheq Mach V Extreme 30 wing and have it setup with advice from Edd Sorenson. Cos most of my dives involves travel by air or boat I'm using fairly light gear like 0.5mm wetsuit, quattros etc. We use 12L Alu tanks here and I usually weight the butt by 2-3lbs as we mostly use Yoke around the region. I also add 4-6 lbs on the harness in the shoulder weight pouches.

The SS Harness plates are strong enough to attach a 2 piece STA and is strong enough to use as back mount for singles diving. In it's simplest form without the multiple SM D rings and a light Mach V 30 wing, it weights under 2kg, great for travel!!

The main issues I've faced so far and I'm not an experienced SM diver by any stretch.

1. Trim, cos my fins aren't that heavy I find it difficult to use them to counteract the weight of a full tank at the beginning of the dive and at the end of the dive the tanks become floaty.

2. Currents and tank banging. In places like Thailand and Indonesia, I find it difficult to deal with the currents and end up hugging the tank to prevent them moving around and bumping me constantly.

3. Boat entry/exit, things get a bit cumbersome with boat entry/exit especially in choppy conditions.

I would like to find a SM instructor around Singapore or Thailand to help me with the details or get the Stealth 2.0 wing if necessary.

My secondary goal is figure out the best method of using SM for single tank tropical boat/shore diving in fairly rough conditions.

My primary goal is design a light travel rig that allows singles tank BM, SM single/multiple tanks to be attached as securely as possible instead of having to deal with floppy tanks yet retains all the benefits of a true SM setup.

I'm a bit of a tinkerer and will reinvent the wheel if possible lol.

 

[Kazeone]

It takes a couple dives to get used to single-tank sidemount, but soon enough you figure out how to compensate with one fin to get back to well trimmed out. I put the single on my left side, and then my left foot has to kick a little harder, but nothing exhausting by any means. Other people say it's about how you position your hips, but whatever works is the right way - it all depends on the shape of your body (like exactly where you need those last couple weights to trim out head-to-feet too). If you shift your weights to compensate for the full tank at the beginning of the dive, you might have to compensate for being heavier on the extra-weight-side by the end of the dive depending on the buoyancy characteristics of your tank.

That being said, double 40's is nice too if you don't need all the gas of double 80s and can find some.

That’s correct. You will either be balanced in the beginning with AL80 on one side and a kilo on the other. Or balanced towards the end with no weight on the opposite side. If I ever do it fun diving with my girlfriend I put one kilo in opposite side of tank hip pocket then move it tank side when I go to the lower d-ring. Then she uses my bp/wing. But otherwise it’s much nicer with 2 tanks. Multiple stages are much nicer in SM than twinset.

 

[АлександрД]

Sorry for necroposting... over 5 years had gone from this topic start...

For me single side sidemount is not a problem. I prefer to use steel cylinders, (10L 200bar aka HP70) - that have average negative buoyancy aroung 2 kg (4.5lbs).
So - when I need to use one tank instead of two - I just move one lead weight (1kg) from left to the right. And balance is stay the same.


My tanks has standard regulators with octopus hoses (all of them) - around 0.8-1m length (3 ft approx). But!
Left tank has two 2nd stages, one I use, another on the tank, under rubber bands. And inflator hose.
Right tank (if I use it) has only one second stage, and nothing else. Under rubber bands on tank.


Also I prefer to have Nx32 in the right tank, and from 6m (10ft) change gas to the right tank.
Using gas just from one tank (in the beggining), till 50 bar (725psi), allow to be comfortable as with one tank, as with two.
And I have all dive on the air, stops in the Nx32, computer I use only as air. Always (till 35m) I have enough safety for PPO2, in case of use Nx32 on the depth - I just start to ascending till 20m. It takes 1-2 min, and safe enough.

When we planning dive till 20m (65ft) - I use just one tank. Deeper - two.

I always can share my gas with buddy. does not matter, as from the left tank, as from the right tank. or I can share my own reg.
Later, in calm, we can separate our tanks, and most simple for me - Just gave him my right tank. e.g.


And I can use 12L "piglet" tanks (short and heavy), but it is not so comfortable, as 10L slim tanks.

 

[Kazeone]

Sorry for necroposting... over 5 years had gone from this topic start...

For me single side sidemount is not a problem. I prefer to use steel cylinders, (10L 200bar aka HP70) - that have average negative buoyancy aroung 2 kg (4.5lbs).
So - when I need to use one tank instead of two - I just move one lead weight (1kg) from left to the right. And balance is stay the same.
View attachment 508385 View attachment 508387 View attachment 508388

My tanks has standard regulators with octopus hoses (all of them) - around 0.8-1m length (3 ft approx). But!
Left tank has two 2nd stages, one I use, another on the tank, under rubber bands. And inflator hose.
Right tank (if I use it) has only one second stage, and nothing else. Under rubber bands on tank.
View attachment 508389 View attachment 508391

Also I prefer to have Nx32 in the right tank, and from 6m (10ft) change gas to the right tank.
Using gas just from one tank (in the beggining), till 50 bar (725psi), allow to be comfortable as with one tank, as with two.
And I have all dive on the air, stops in the Nx32, computer I use only as air. Always (till 35m) I have enough safety for PPO2, in case of use Nx32 on the depth - I just start to ascending till 20m. It takes 1-2 min, and safe enough.
View attachment 508390
When we planning dive till 20m (65ft) - I use just one tank. Deeper - two.

I always can share my gas with buddy. does not matter, as from the left tank, as from the right tank. or I can share my own reg.
Later, in calm, we can separate our tanks, and most simple for me - Just gave him my right tank. e.g.
View attachment 508384

And I can use 12L "piglet" tanks (short and heavy), but it is not so comfortable, as 10L slim tanks.
View attachment 508386

Sorry for necroposting... over 5 years had gone from this topic start...

For me single side sidemount is not a problem. I prefer to use steel cylinders, (10L 200bar aka HP70) - that have average negative buoyancy aroung 2 kg (4.5lbs).
So - when I need to use one tank instead of two - I just move one lead weight (1kg) from left to the right. And balance is stay the same.
View attachment 508385 View attachment 508387 View attachment 508388

My tanks has standard regulators with octopus hoses (all of them) - around 0.8-1m length (3 ft approx). But!
Left tank has two 2nd stages, one I use, another on the tank, under rubber bands. And inflator hose.
Right tank (if I use it) has only one second stage, and nothing else. Under rubber bands on tank.
View attachment 508389 View attachment 508391

Also I prefer to have Nx32 in the right tank, and from 6m (10ft) change gas to the right tank.
Using gas just from one tank (in the beggining), till 50 bar (725psi), allow to be comfortable as with one tank, as with two.
And I have all dive on the air, stops in the Nx32, computer I use only as air. Always (till 35m) I have enough safety for PPO2, in case of use Nx32 on the depth - I just start to ascending till 20m. It takes 1-2 min, and safe enough.
View attachment 508390
When we planning dive till 20m (65ft) - I use just one tank. Deeper - two.

I always can share my gas with buddy. does not matter, as from the left tank, as from the right tank. or I can share my own reg.
Later, in calm, we can separate our tanks, and most simple for me - Just gave him my right tank. e.g.
View attachment 508384

And I can use 12L "piglet" tanks (short and heavy), but it is not so comfortable, as 10L slim tanks.
View attachment 508386

How come your tank is only trimmed out in one pic?

 

[Kazeone]

How come your tank is only trimmed out in one pic?

Maybe 2

 

[АлександрД]

I use just one attachment point at the bottom side, and in the movement tank can shaking. It is not disturb me In static it is like on the first picture.
For fatty tanks it is not so easy to set it in good popsition.

 

[happy-diver]

How come your tank is only trimmed out in one pic?

Maybe 2

It's called diving mate, have you tried it


You have a great passion Alexander