Gas Management With Sidemount

[lermontov]

So this may sound like a dumb question but...what are y'all's thoughts on side mounting 104s and the practicality of it. I currently side mount AL80s or LP 85s, but my buddy dives back mount 95s and my other buddy dives back mount 104s. I'm wanting to carry larger tanks as with NAUI cave 1 I cannot carry stage bottles. Thanks in advance for the advice/recommendations!

youll also need to understand gas matching mathematics

 

[lermontov]

Still not. It's just showing a tiny white square

its the same info as brent has in the wreck manual about sidemount

 

[DiveClimbRide]

its the same info as brent has in the wreck manual about sidemount

Ah right no worries then

 

[tbone1004]

If I financially could I'd start cave 2 tomorrow but unfortunately I have to wait a little bit before undertaking that expense. Also wanting to get more cave experience before taking it. Only had Cave 1 for 2 months.

stay with the bottles you have and tell your buddies to get over it, you'll be dumping $500ish for a new set of tanks that is like half the cost of Cave 2 and it MIGHT get you 10% farther into the cave because you have the added mass that you have to move with the 104's and you'll be less efficient. You also have to contend with bottles that act VERY differently to your current tanks and will require you to basically relearn sidemount. With 104's you are basically strapping a 4lb weight onto each of your LP85's *yes, they are that negative*, and that's going to screw up your weighting, your trim, you MUST dive a sidemount rig with a butt plate and you're going to have to use it, it's a completely new ballgame. The AL80's to LP85's isn't terribly huge of a change, but going to 104's is a nightmare and there is a reason that literally no one uses them in sidemount. Wonderful backmount bottles, horrific sidemount bottles.
The 104's aren't going to get you more cave experience and are likely only to set you back farther in your cave progression. If you need bigger bottles you really need to go with Fabers to not royally screw up your sidemount experience. 108's are going to be essentially an 8" version of your 85's with similar length and buoyancy characteristics. Since they are about 6lbs lighter each than the 104's, you will actually get a bit farther in the cave which is good. Probably not the full 30% that you get on paper, at least not until you're more experienced, but it will help.

 

[Matthew Spears]

stay with the bottles you have and tell your buddies to get over it, you'll be dumping $500ish for a new set of tanks that is like half the cost of Cave 2 and it MIGHT get you 10% farther into the cave because you have the added mass that you have to move with the 104's and you'll be less efficient. You also have to contend with bottles that act VERY differently to your current tanks and will require you to basically relearn sidemount. With 104's you are basically strapping a 4lb weight onto each of your LP85's *yes, they are that negative*, and that's going to screw up your weighting, your trim, you MUST dive a sidemount rig with a butt plate and you're going to have to use it, it's a completely new ballgame. The AL80's to LP85's isn't terribly huge of a change, but going to 104's is a nightmare and there is a reason that literally no one uses them in sidemount. Wonderful backmount bottles, horrific sidemount bottles.
The 104's aren't going to get you more cave experience and are likely only to set you back farther in your cave progression. If you need bigger bottles you really need to go with Fabers to not royally screw up your sidemount experience. 108's are going to be essentially an 8" version of your 85's with similar length and buoyancy characteristics. Since they are about 6lbs lighter each than the 104's, you will actually get a bit farther in the cave which is good. Probably not the full 30% that you get on paper, at least not until you're more experienced, but it will help.

Thank you for all your input/advice, it's greatly appreciated!

 

[halocline]

I switch every 200 PSI, starting with the right tank. (Assuming they start the dive equally filled) Ideally the left tank never gets lower than the right tank, which was counter intuitive to me before I took my cave sidemount class, but now it makes sense. That left tank is my reserve in the event of an airshare.

Since regulator switches don't bother me in the least, I see no downside to this practice and the upside is that the tanks stay nice and balanced.

 

[Matthew Spears]

I switch every 200 PSI, starting with the right tank. (Assuming they start the dive equally filled) Ideally the left tank never gets lower than the right tank, which was counter intuitive to me before I took my cave sidemount class, but now it makes sense. That left tank is my reserve in the event of an airshare.

Since regulator switches don't bother me in the least, I see no downside to this practice and the upside is that the tanks stay nice and balanced.

I normally start on my right tank, breath it 500 then switch to my left and switch every 500 after. once both tanks hit 2,000-2300 on the exit I move them down. Every 200 seems like it'd get annoying having to do all those switches but I guess it' really personal preference.

 

[wetb4igetinthewater]

I'm amazed this thread is still going five years after I started it! Just noticed it as I was cruising new posts. Had to catchup. Thanks to all who have participated as there were many useful side discussions.

 

[halocline]

I normally start on my right tank, breath it 500 then switch to my left and switch every 500 after. once both tanks hit 2,000-2300 on the exit I move them down. Every 200 seems like it'd get annoying having to do all those switches but I guess it' really personal preference.

If I let one tank get 500 PSI lower than the other I would really feel the unbalance. Part of that might be using AL80s, they really get buoyant quickly. Plus, I'm doing this in caves, where redundancy and team work can be life saving. So I prefer to keep them as balanced as possible in the event of an emergency air share. To me, regulator switches are not annoying in the least. Honestly, if they present any significant distraction or task loading issues, then maybe that's a skills problem.

This is the way I was taught. I remember in my class being surprised that I was told I needed to switch that frequently, but now with some experience I get the advantage.

 

[Matthew Spears]

If I let one tank get 500 PSI lower than the other I would really feel the unbalance. Part of that might be using AL80s, they really get buoyant quickly. Plus, I'm doing this in caves, where redundancy and team work can be life saving. So I prefer to keep them as balanced as possible in the event of an emergency air share. To me, regulator switches are not annoying in the least. Honestly, if they present any significant distraction or task loading issues, then maybe that's a skills problem.

This is the way I was taught. I remember in my class being surprised that I was told I needed to switch that frequently, but now with some experience I get the advantage.

I'll have to give it a try on my next cave dive! My instructor had me switch at my preference and depending on where we were in a cave cause as you know, switching in small areas is a B****, but I'm always open to trying to new ideas and diving methods.