I was taught 500/1000. Hasn't been a problem from a balance perspective. I guess more frequent switches make sense for gas sharing purposes.
I don't get side mount?
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I was taught 500/1000. Hasn't been a problem from a balance perspective. I guess more frequent switches make sense for gas sharing purposes.
SanDiegoSidemount
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Victor's just a precise guy. I can see in situations where balance and buoyancy are super-critical, more frequent switches will keep you more nicely balanced. Like in silty caves.
I learned the same as you: 500/1000. This seems to work fine for the mostly OW dives I do, and keeps me having to switch quite as often.
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I tend to do it by time ... 10 minutes on, 10 minutes off. However you do it, the concept is the same ... don't let one tank get so low you couldn't donate it ... or use it ... to exit in an OOA emergency.
... Bob (Grateful Diver)
... Bob (Grateful Diver)
I have a hard time imagining walking with the tank necks clipped off to my hip d-rings. I think the tanks would drag, or at least hit me in the ankles. Maybe I'll have to try it. I wish I'd been able to connect with you, SanDiegoSidemount, while you were here. I have the gear and the tanks -- I just can't figure out a way to use it all that works.
SanDiegoSidemount
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The real lesson here is that there are tons of "tricks" you can try, just like in backmount. However, the fewer local sidemount divers you have to learn from, the harder those "tricks" are to come by. There are so few active sidemount divers in the PNW, it's got to be much harder to refine your game. There are simply fewer people to compare notes with, who dive sidemount in the same conditions as you do.
Combine that with a very strong trend towards backmount doubles in the PNW tech diving crowd, and you probably don't get a lot of practice in sidemount without feeling like a square peg amongst your buddies. It's probably just easier to go with the flow and wear the same gear as the other folks.
Jeff at the Seattle Aquarium feels the same way: he has a great sidemount rig, but hesitates to use it because his team's habits are so centered around the "tricks" of backmount diving.
The low-clip trick is San Diego beach specific as far as I know. We use it around here to keep the lowest possible center of gravity entering in heavier surf. But I was thinking it might make carrying tanks for a don-in-the-water type of entry more convenient too.
victorzamora
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Actually, the reason I do it this way is that the math tends to be easier. I dive mostly steels, so "full" is 3600PSI. Thirds (fairly cave-specific) means 1200psi of usable gas, so it's easier to switch on the 300/600. Even on AL80s I like switching every 300/600, but that's because that allows me to accommodate the swing to tail-up more easily on most AL80s (as in, they do it at almost the same time based upon where my gas switches occur).
On AL80s the math is easier to do it 500/1000, but I think it works better in steels and AL80s so I shoot for 300/600. I will say, though, that outside of the cave I tend to care a whole lot less about perfect gas switches and have gone as long as 1200 before the balance really started bothering me.....but that was because I was diving a GoPro and forgot about trim.
Dhboner
Contributor
Sidemount Diving: It?s Not Just for Caves | SDI | TDI | ERDI There is a great table for reg switches embeded in this great article. It is based on sixths and thirds and works really well (at least for me).
---------- Post added September 17th, 2014 at 08:45 AM ----------
The article by the way was authored by my sidemount instructor Steve Lewis!
---------- Post added September 17th, 2014 at 08:45 AM ----------
The article by the way was authored by my sidemount instructor Steve Lewis!
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the 300/600 mentality is really cave specific because it allows you to dive thirds as victor said. I tend to breathe right tank down a third, then left tank to third, turn, and stay on the left tank most of the way out. When I hit 2/3's on that I'll switch back to the right for the rest of the ride. That works for tanks in the HP100 range because it's a little less than 3lb weight difference at switch which is manageable.
The PST tanks exhibit more stable buoyancy swings, so depending on how large your tanks are, and if they get butt floaty depends on when I switch.
I do 600psi on my left, 1200psi on my right, then 1200psi on my left in my HP120's, that's about a 1.5lb offset in buoyancy for 600psi difference. In OW I tend to a bit more liberal and will typically do it in 1000psi increments depending on my mood. Down to 2500psi on right, down to 2000 psi on left, then switch a bit more frequently after that, but it takes a long bloody time in OW to breathe down that far.
Like everything for me in diving, adapt to the conditions at hand.
The PST tanks exhibit more stable buoyancy swings, so depending on how large your tanks are, and if they get butt floaty depends on when I switch.
I do 600psi on my left, 1200psi on my right, then 1200psi on my left in my HP120's, that's about a 1.5lb offset in buoyancy for 600psi difference. In OW I tend to a bit more liberal and will typically do it in 1000psi increments depending on my mood. Down to 2500psi on right, down to 2000 psi on left, then switch a bit more frequently after that, but it takes a long bloody time in OW to breathe down that far.
Like everything for me in diving, adapt to the conditions at hand.
AfterDark
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I've tried SM and although I didn't fall in love, I can see situations where SM in OW shore diving could be easier than the BM IDs I use for solo. If I had the money to throw for a system that I'd use sometimes I'd probably own a SM rig. Since my collar is blue and I can barely afford to heat my house I enjoy BM diving. I "get" it, what I don't get is the come to Jesus moment some people seem to have after trying SM.
Remind me of DIR all those years ago!
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