Question Sidemounts on a Liveaboard

[LFMarm]

if you really want to stick to sm-like set up, then consider doing monkey diving (sm with just 1 left cylinder)

you put long and shot hoses on the same reg, long hose remains fully stowed away

in fresh water you don't need any weight changes

in salt water, i would definitely put a 1.5-2kg weight on the right side to counterbalance the tank

Why? Even if doing 1h dives with rest of group I would not give away redundancy in case of need and balance/trim of having both tanks.

 

[Dan]

I've only been on 10 liveaboards, have not seen anybody use sidemount. I wonder whether they want you to use one tank or two, The dive time is generally set +/- an hour. You've got to be kidding regarding changing valves. Let us know how it works out for you.

I have seen 2 guys diving with sidemount, one in Red Sea and one in Sangalaki on White Manta. You can see in 5:04 minutes of my video, below:

 

[gmerick]

I've done liveaboard sidemount. I've never encountered mirrored valves. Best case is when they have AL63's with DIN valves. Most common is a pair of standard AL80s short posts, and INT (yoke) valves. Sidemount is not impossible with yoke adapters on standard valves, merely inconvenient. Under pressure it is very difficult to turn the yoke screw, being careful, the bungee can be secured around it. To avoid being the "slow" diver, get your kit-up routine down before the trip. Practice coping with bungees on those "standard" tanks, and how to re-board the boat without assistance. To keep the dive crew happy, discuss dive logistics. Four daily dives and a night dive means be climbing the ladder at one hour with over half your air left unless the crew has explicitly said differently. Ask the dive crew to pick a station for your gear, they know the on-deck traffic patterns, and where there is enough room to walk with your tanks slung. Think about your entry. AquaCat is very SM friendly, but the dive deck is 8 feet over the water. Juliet is even taller. Can you descend a ladder to a dive stage while wearing everything, and carrying camera and scooter? Can you do a giant stride from 8 feet up? Consider what you'll do if the dive site requires a live drop or dynamic entry. Getting 12 divers in the water in half a minute or so gets exciting.

 

[scubayinzer412]

i always go sidemount on liveaboards, never had troubles. and SM diver are stress for the crew isnt true. i am always the most autonom diver, clear my tanks in the safty stop.

 

[Underwater Tourist]

Why? Even if doing 1h dives with rest of group I would not give away redundancy in case of need and balance/trim of having both tanks.

My understanding is that OP will be doing recreational dives, in that case do you really need redundancy? As for balance, a little body tension with 2kg weight on the right side solves everything and you really can’t tell that you are diving with 1 tank only (if OP dives with a dry suit, then it’s even easier)

Anyhow, I just mentioned that option for the OP to consider, how much he values redundancy and other pros/cons of sm will ultimately be up to him

 

[O-ring]

The sidemount divers I have been on LOBs with were all diving singles. I don't know if they asked for 2 and were refused or if they preferred one for shallow rec diving. With 2 I think it might have been more challenging for them boarding the pangas in Socorro off the back of the boat, but it also might have been easier getting back on the pangas post dive since they could just hand up their tank and climb in vs. doffing a BM rig in the water and handing that up.

 

[O-ring]

I dug up a couple pics of the Socorro SM divers in case those are helpful.

 

[wKkaY]

A friend of mine went on a liveaboard with me and dove single tank sm. He had a cave diving trip to Tulum right after and didn't want to bring an extra BPW.

It turned out to be fine. Boarding the zodiac needed a bit of assistance from the crew to pass the tank to him. But after that he's self-sufficient on the zodiac kitting up and backrolling.

Getting back on the zodiac and on to the ship it was in fact easier on the crew as they only needed to lift his tank up as opposed to complete sets of BPW gear.

 

[billgraham]

Most often, you're going to get tanks with the yoke valves. If you have adapters for your DIN sidemount regs, it there's an additional handwheel to put the bungee over. I always say, "I get two tanks, right? I'm just taking both of them in the water at the same time."

 

[O-ring]

Most often, you're going to get tanks with the yoke valves. If you have adapters for your DIN sidemount regs, it there's an additional handwheel to put the bungee over. I always say, "I get two tanks, right? I'm just taking both of them in the water at the same time."

That might work as long as the number of sidemount folks is pretty low. Using the Belle Amie as an example, she carries something like 32 divers and her SOP is "hook BC up to tank when you arrive and then they refill your tank while attached to your BC between dives". That's the same with the Aggressors I have been on. So at any given moment 32 divers in the water means 32 tanks in the water. I know they carry spares, but if 32 people showed up and expected to use 64 tanks I don't know that they have enough on board to accommodate everyone.