Sidemount, seems cool but why give it a try ?

[Lorenzoid]

Hello all,

I start to have a lot of dive, more I dive more I meet Sidemount divers, they are all telling me that's the best way to dive.

I can understand the point in cave or wreck but not for fun dives. Can someone explain me why is that so great ?

Are you comparing sidemount to single-tank "fun dives" or twinset "fun dives"? If the former, and if you have no back pain issues, and if you have some other mechanism in mind to deal with gas supply failures--for example, you are of the philosophy that your buddy carries your extra gas--then I think sidemount just needlessly adds complexity. A single-tank fun dive with an Al 80 is a joy. If all you need is a single tank, and you think it feels light as a feather on your back, then why complicate things with having to manage two tanks? The more stuff, the less "fun."

"Single-tank sidemount" intrigues me, but I can't help thinking that there must be some drawback. If diving were as simple as keeping a tank by one's side, why was that configuration not invented first, and/or why did it not become the standard? Strapping a tank on my back is not the first way that would occur to me to take a tank with me underwater.

 

[stuartv]

If diving were as simple as keeping a tank by one's side, why was that configuration not invented first, and/or why did it not become the standard? Strapping a tank on my back is not the first way that would occur to me to take a tank with me underwater.

My suspicion? The original double hose style of regulator only works well if the reg is very close to your lungs (simplistically speaking). I think hydrostatic (?) breathing resistance would be unacceptable using that type of regulator on a side mounted tank.

 

[Luis H]

My suspicion? The original double hose style of regulator only works well if the reg is very close to your lungs (simplistically speaking). I think hydrostatic (?) breathing resistance would be unacceptable using that type of regulator on a side mounted tank.

That is a true statement. And IMHO, that is also probably the major reason we use tanks with the valve on the top, most of the early regulators were double hose.

Some of the very early single hose regulators used a first stage mounted on a bottom tank valve. The Scott Hydro Pack was one example with the bottom mounted valve. The SCBA like the Scott Air Pack (used by fire fighters) continue to have the valve on the bottom for better access, but in Scuba the top mounted valve was better for the double hose regulator.

 

[raftingtigger]

Probably like QWERTY the keyboard. The pattern was to SLOW down the typist to prevent jamming keys

 

[WarrenZ]

Early cave divers were diving sumps in the 60s with a single sidemount before it became a thing.

Think about it this way everyone can picture a backpack holding heavy items If you are trying to sell people on a new sport like scuba wouldnt they feel better with a familiar backpack rather than "Tie this tank to your armpit with bungie cord and swim around dont worry it will be fine".

To me the draw of sidemount is all of the older tech divers I would talk to were talking about bad knees backs hips etc that were bothered by the weight of doubles. I see sidemont as a way to take care of myself for the future. Besides I can dive with any tanks I can strap on now.

 

[Lorenzoid]

I'd like to learn more about single-tank sidemount for easy rec dives (or what the OP calls "fun dives"). Why does single-tank SM seem to get so little attention? Simply moving a tank from one's back to one's side seems like it couldn't be easier. Essentially nothing new to learn--no need to equalize two tanks, etc. I would think safety procedures would be essentially the same as backmount.

Would it make changing tanks on a boat more cumbersome?--removing from the harness, etc.? Is that why double-tank SM remains more common even for easy rec dives?--so you can do two dives without changing out tanks?

 

[kafkaland]

I'd like to learn more about single-tank sidemount for easy rec dives (or what the OP calls "fun dives"). Why does single-tank SM seem to get so little attention? Simply moving a tank from one's back to one's side seems like it couldn't be easier. Essentially nothing new to learn--no need to equalize two tanks, etc. I would think safety procedures would be essentially the same as backmount.

Would it make changing tanks on a boat more cumbersome?--removing from the harness, etc.? Is that why double-tank SM remains more common even for easy rec dives?--so you can do two dives without changing out tanks?

Single-tank backmount seems unbalanced to me. I feel like I'm rolling to one side. Two tanks - that's where sidemount excels. Perfectly balanced, it just feels very easy to dive once trim is dialed in. More bottles, and I'm not so sure any more. One deco or stage bottle makes me slightly unbalanced, but it's ok. I can see taking a second stage / deco bottle in that configuration with similar drawbacks, but that's it. I suspect although I haven't tried it, that once you need the fifth bottle for let's say advanced trimix dives, you'd want to use the real estate on your back for the back gas, or it will just get too crowded on your sides.

 

[DaveJo127]

Redundancy. It's reassuring to have two independent tanks under your arms where you can get to them easily. For this reason I prefer sidemount when diving solo. It also trims out nicely once you have your rig dialed in. And of course... you will look cool.

Honestly though for a fun recreational dive I'd rather just dive single backmount with a buddy or group. It's simpler and much easier to set up, especially on a crowded and rocky dive boat. If you have no aspirations of tech diving and no desire to try sidemount, then I wouldn't worry about it. (IMO)

 

[raftingtigger]

Redundancy. It's reassuring to have two independent tanks under your arms where you can get to them easily. For this reason I prefer sidemount when diving solo. It also trims out nicely once you have your rig dialed in. And of course... you will look cool.

Very balanced, free feeling, and redundant for solo dives. It also lets me dive longer for each shore entry. My recent Bonaire trip was done this way. I tried using my 13 cuft pony for my solo dives and found double SM to be better. Not an issue with the entries/exits. I actually feel more stable with entering and exiting SM than BM.

Honestly though for a fun recreational dive I'd rather just dive single backmount with a buddy or group. It's simpler and much easier to set up, especially on a crowded and rocky dive boat. If you have no aspirations of tech diving and no desire to try sidemount, then I wouldn't worry about it. (IMO)

BM easier to set up on a boat? Not in my limited experience. Did 6 boat dive on my recent trip and I took up less space, was ready sooner, and packed up quicker after the dive than any of the BM divers. I did rig my gear for single SM (the Divemaster wouldn't let me do doubles - thought I would stay down too long). Key is you can wear the harness going out and coming in - or at least put the harness on before arriving. Can't do that with BM as it tethers you to the tank.

FYI, my single SM diving with a group was with a short bungeed 2nd and a long hose donatable 2nd. Entry was giant stride, and exit was with tank still clipped. I didn't even need to hand up fins or camera rig.

Lastly, yes single SM can be a little unbalanced. Since I was using an Al 80 and they end up positive I just put all my weight (4#) on the same side as the tank. This balanced things nicely.

 

[Coztick]

My sentiments exactly!
For single tank, I clip 2 3lb. weights on 7" leashes to the lumbar plate.
Start the dive with weight on the opposite side and move them individually to the other side behind you without unclipping them. They just lay at your side below your hip.
Next time tell the DM you will take both tanks on both dives!